JP6171504B2 - Control device for internal combustion engine - Google Patents

Description

  The present invention relates to a control device that realizes requests related to various functions of an internal combustion engine by cooperative control of a plurality of actuators.

  Regarding a control device for an internal combustion engine, for example, as disclosed in Patent Document 1 and Patent Document 2, a hierarchical control structure is provided, and a signal is transmitted in one direction from an upper hierarchy to a lower hierarchy. Are known. In the examples described in the above-mentioned documents, the basic three function requirements in the internal combustion engine for vehicles such as drivability, exhaust gas, and fuel consumption in the highest requirement generation hierarchy are the three types of torque, efficiency, and air-fuel ratio. A required value expressed in the physical quantity is generated.

  Then, the signal of the required value is transmitted to the lower physical quantity arbitration hierarchy, where the required values are aggregated for each of torque, efficiency and air-fuel ratio, and arbitrated to one required value according to a predetermined rule. . Each of the torque, efficiency, and air-fuel ratio signals adjusted in this way is transmitted to the lower control amount setting layer, where each required value is adjusted based on the mutual relationship, Set the control amount.

  In this way, the demand for the internal combustion engine is expressed by a combination of three kinds of physical quantities of torque, efficiency, and air-fuel ratio, and by arbitrating, the entire internal combustion engine to be realized by the control regardless of the characteristics and types of the actuator Therefore, it is possible to realize suitable control that satisfies the basic requirements of the internal combustion engine such as drivability, exhaust gas, and fuel consumption in a well-balanced manner.

JP 2009-47101 A JP 2009-47102 A

  By the way, in an internal combustion engine equipped with an in-cylinder injection fuel injection valve that directly injects fuel into the cylinder, fuel injection is performed to form a good mixture in the cylinder by taking advantage of the high degree of freedom of injection control. There is a request to change the mode of the above as appropriate. However, since the injection mode is the operation of the fuel injection valve itself, once it is converted into a physical quantity such as torque and efficiency, and then adjusted, it is an extra computational load. Give rise to

  Therefore, it is conceivable that the mode of injection is expressed not as a physical quantity but as a control quantity (injection control quantity) of the fuel injection valve, and in this case, the problem is how to express specifically. Become. That is, there are various control amounts representing the mode of injection, for example, the number of injections, the injection timing of each injection, the injection ratio, etc., and when trying to mediate all of these together, the logic becomes very complex. .

  In particular, when a general port injection fuel injection valve is provided in addition to the in-cylinder injection fuel injection valve, the process of forming a mixture of fuels respectively injected by the different types of fuel injection valves Since the fuel injection is greatly different, how many times the fuel is injected by which fuel injection valve greatly affects the mixture distribution and its combustibility.

  In addition, since the air-fuel mixture is more difficult to form at the start of the internal combustion engine and the combustion state is likely to deteriorate, the preferred fuel injection mode differs from that during operation. There is a different demand for timing control than during normal operation. In such a specific state, it is necessary to ensure the synchronism between the fuel injection control and the throttle and ignition control.

  In view of these points, an object of the present invention is to provide a control device having a hierarchical structure in which basic requirements for an internal combustion engine are satisfied in a balanced manner by means of physical quantity arbitration, without increasing the load of control computations. It is intended to suitably adjust various requests related to injection and to ensure simultaneity with control of other actuators such as a throttle in a specific state such as at the time of starting.

  In order to achieve the above object, the present invention provides an arbitration hierarchy in which the required value expressed by the control amount (injection control quantity) of the fuel injection valve is transmitted without going through the physical quantity arbitration hierarchy, In addition to arbitration, the arbitration result is output as a set of numerical values that can identify the type of fuel injection valve and that the internal combustion engine is in a specific state.

Specifically, the present invention is directed to a control device for an internal combustion engine that realizes requests related to various functions of the internal combustion engine by cooperatively controlling a plurality of actuators related to the operation of the internal combustion engine. A request generation hierarchy for outputting a value, a physical quantity arbitration hierarchy that is provided below the request generation hierarchy, aggregates and mediates those of the request values expressed in a predetermined physical quantity, and is provided below the physical quantity arbitration hierarchy And a control amount setting layer for setting the control amount of the actuator based on the arbitrated request value, and from the upper layer to the lower layer in the order of the request generation layer, the physical amount arbitration layer, and the control amount setting layer It has a hierarchical control structure in which signals are transmitted in one direction.
Further, below the control amount setting hierarchy, a control amount arbitration hierarchy in which a request value output from the request generation hierarchy is expressed by the control amount of the actuator is transmitted without passing through the physical quantity arbitration hierarchy The request values transmitted here are aggregated and arbitrated.

The plurality of actuators include a first injection valve arranged to inject fuel directly into the cylinder and a second injection valve arranged to inject fuel into the intake port of each cylinder. preparative are included, wherein the control amount arbitration hierarchy, at least as the injection control amount regarding operation before Symbol first and second injection valve, the injection frequency of the first and second injection valve, the injection timing, and their An injection control arbitration unit that adjusts the injection ratio is provided .
The request value transmitted from the request generation hierarchy to the injection control arbitration unit without going through the physical quantity arbitration hierarchy is in each state corresponding to each of the internal combustion engines in a plurality of specific states. And a three-digit numerical value expressing the number of injections of the first and second injection valves in each state by each digit, and each state has a priority in advance. Is set.
Then, the injection control arbitration unit arbitrates the number of injections of the first and second injection valves according to the priority order, separately from the injection timing and the injection ratio, and the arbitration result is obtained as the first and second injections . The number of injections of the two injection valves and the three-digit numerical value of the identification number are output.

  In the control apparatus for an internal combustion engine configured as described above, first, requests relating to various functions of the internal combustion engine are expressed by a predetermined physical quantity (for example, torque, efficiency, air-fuel ratio, etc.), and arbitrated. The control amount of each actuator is set based on the value. As a result, a plurality of actuators are controlled in a coordinated manner, and basic function requirements (for example, drivability, exhaust gas, fuel consumption, etc.) of the internal combustion engine are satisfied in a well-balanced manner.

At this time, the request regarding the operation of the fuel injection valve is expressed by various injection control amounts such as the number of injections of the first and second injection valves , the injection timing and the injection ratio of each time, and the physical quantity arbitration hierarchy from the request generation hierarchy. And without passing through the control amount setting layer, it is transmitted to the control amount arbitration layer below it. And it is arbitrated in an injection control arbitration part, and it is reflected in the control amount of a fuel injection valve. That is, the injection control amount is adjusted without going through the physical amount adjustment, and is reflected in the control of the internal combustion engine, so that there is no calculation load for conversion into the physical amount.

From yet a further said injection control arbitration unit, the injection control of the arbitration result, identifiable identification and injection frequency of the first and second injection valves, that the engine is in a particular state, such as during start-up It is output as a 3-digit number consisting of a number. Since the type of the fuel injection valve that performs the fuel injection has a great influence on the air-fuel mixture formation, various requests can be suitably reflected in the combustion state by outputting the fuel injection valve.

  For identifying the specific state, for example, “1” is set during normal operation of the internal combustion engine, “2” is set during rapid warm-up of a catalyst having different requirements, and “3” is set when the engine is started. If the internal combustion engine is in a specific state such as starting if it is set in advance in correspondence with a specific state, the throttle control that cooperates with the fuel injection control in each of these specific states. And synchronization with ignition control can be ensured.

  In other words, the specific state means that the fuel injection control must be synchronized with the control of other actuators such as a throttle valve and an igniter, for example, starting in a stratified combustion state, Examples include rapid warm-up and cylinder deactivation (control for deactivating several cylinders).

In more details, the internal combustion engine, directly into the cylinder, a first injection valve arranged to inject fuel, a second injection valve arranged to inject fuel into the intake port for each cylinder and comprises both, in this case, since such respective injection frequency of the two injection events can be changed, the degree of freedom of injection control more, although the higher expression of jetting modes is more complicated become.

In contrast, the injection control arbitration unit as described above is, at least, arbitrates injection number of fuel by the first contact and the second injection valve as one of the injection control amount, the arbitration result, the The number of fuel injections by the first injection valve, the number of fuel injections by the second injection valve, and the identification number for identifying that the internal combustion engine is in a specific state are expressed in three digits. It is output as a numeric value. This in to Rukoto, the injection number of the first and second injection valve can be represented in brief format.

  In addition, even in an internal combustion engine having a different number of fuel injection valves, for example, without a second injection valve and having only the first injection valve, it is only necessary to set one of the three-digit numerical values to zero (0). There is no need to change the format of the injection mode. Therefore, a common control program can be easily applied to internal combustion engines with different specifications, and the number of changes in the control program can be reduced even when the specifications change.

Further, such a three-digit numerical value is used not only as an output of the arbitration result from the injection control arbitration unit, but also as a request value transmitted to the injection control arbitration unit, and the number of identifications included therein Thus, it is possible to identify that the internal combustion engine is in a plurality of specific states such as stratified start and rapid warm-up of the catalyst, and it is also possible to identify priorities set in advance for these states. Then, according to this priority order, the injection control arbitration unit arbitrates the number of injections of the first and second injection valves.

Preferably, the number of injections of the first and second injection valves in a predetermined operation state of the internal combustion engine may be preset in the injection control arbitration unit as the basic number of injections. The predetermined operating state is a so-called rated operating state of the internal combustion engine that is most frequently used in a normal vehicle or the like, and is set in advance by an experiment or the like. If the number of injections (basic injection number) of the first and second injection valves in this operating state is set in advance in the injection control arbitration unit, a signal of the required value of the number of injections is output from the request generation hierarchy in the normal operating state This eliminates the need to do so, and simplifies the processing.

  According to the present invention, first, basic functional requirements of an internal combustion engine, such as drivability, exhaust gas, and fuel consumption, are expressed as physical quantities, and arbitrated in a physical quantity arbitration hierarchy, so that the basic requirements are satisfied in a balanced manner. Such suitable control can be realized. Moreover, the request | requirement regarding operation | movement of a fuel injection valve can be suitably reflected in control of an internal combustion engine, without increasing calculation load by adjusting as an injection control amount without going through physical quantity adjustment.

At that time, the required value of the injection control amount and the arbitration result are set to a three-digit value consisting of the number of injections of the first and second injection valves and the identification number of a specific state of the engine, thereby relating to the injection control. It is possible to achieve suitable fuel injection control while suitably adjusting various requirements and ensuring simultaneity with other controls such as throttle and ignition.

It is a block diagram which shows an example of the internal combustion engine in connection with embodiment of this invention. It is a block diagram which shows an example of ECU in connection with embodiment. It is a block diagram which shows the hierarchical structure of the control apparatus as embodiment. It is a block diagram shown about the arbitration of the injection control amount in an injection function arbitration part. It is a block diagram which shows an example of a structure of an injector drive control part.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the embodiment, a case will be described in which the control device of the present invention is applied to an internal combustion engine (hereinafter referred to as an engine) mounted on an automobile, in particular, a spark ignition engine.

[Engine configuration example]
Below, with reference to FIG. 1, an example of a structure of the spark ignition type engine 1 concerning embodiment is demonstrated first. Although only the configuration of one cylinder 2 in the main body portion of the engine 1 is shown in the drawing, the engine 1 is, for example, an in-line four-cylinder engine, and the cylinder 2 formed in the cylinder block 1a has upper and lower portions in the drawing. The piston 3 is accommodated so as to reciprocate in the direction. A cylinder head 1b is assembled to the upper part of the cylinder block 1a, and a space between the lower surface thereof and the upper surface of the piston 3 serves as a combustion chamber.

  The piston 3 is connected to a crankshaft 5 via a connecting rod 4, and the crankshaft 5 is accommodated in a crankcase at the bottom of the cylinder block 1a. A rotor 301a is attached to the crankshaft 5, and a crank position sensor 301 comprising, for example, an electromagnetic pickup is disposed in the vicinity of the rotor. The crank position sensor 301 outputs a pulse signal when the outer teeth of the rotor 301a pass. The engine speed can be calculated from this signal.

  Further, a water jacket is formed on the side wall of the cylinder block 1a so as to surround the cylinder 2, and a water temperature sensor 303 is disposed here so as to detect the temperature of the engine cooling water w. A lower portion of the cylinder block 1a is expanded downward to form an upper half of the crankcase, and an oil pan 1c is attached below the lower half of the crankcase. The oil pan 1c stores lubricating oil (engine oil) supplied to each part of the engine.

  On the other hand, a spark plug 6 is disposed in the cylinder head 1b so as to face the combustion chamber in the cylinder 2, and a high voltage is supplied to the electrode from the igniter 7. Thus, the timing when the high voltage is supplied and the ignition plug 6 is energized, that is, the ignition timing of the engine 1 is adjusted by the igniter 7. That is, the igniter 7 is an actuator that can adjust the ignition timing of the engine 1 and is controlled by an ECU (Electronic Control Unit) 500 described later.

  The cylinder head 1b is formed with an intake port 11a and an exhaust port 12a so as to open facing the combustion chamber in the cylinder 2, respectively. An intake manifold 11b communicates with the intake port 11a and constitutes a downstream side of the intake air flow in the intake passage 11. An exhaust manifold 12b communicates with the exhaust port 12a and constitutes an upstream side of the exhaust gas flow in the exhaust passage 12.

  An air flow meter 304 (see FIG. 2) for detecting the intake air amount is disposed on the upstream side of the intake passage 11 in the vicinity of an air cleaner (not shown), and for adjusting the intake air amount on the downstream side thereof. A throttle valve 8 is provided. The intake passage 11 (intake manifold 11b) is also provided with an intake air temperature sensor 307 (see FIG. 2) for detecting the temperature (intake air temperature) of air before being taken into the engine 1.

  In this example, the throttle valve 8 is mechanically disconnected from an accelerator pedal (not shown) and is driven by an electric throttle motor 8a to adjust its opening. A signal from a throttle opening sensor 305 that detects the throttle opening is transmitted to an ECU 500 described later. The ECU 500 controls the throttle motor 8a so that a suitable intake air amount can be obtained according to the operating state of the engine 1. That is, the throttle valve 8 is an actuator that adjusts the intake air amount of the engine 1 (related to the operation of the internal combustion engine).

  As described above, the opening of the intake port 11a that faces the combustion chamber is opened and closed by the intake valve 13, whereby the intake passage 11 and the combustion chamber are communicated or blocked. Similarly, the opening of the exhaust port 12a is opened and closed by an exhaust valve 14, thereby communicating or blocking the exhaust passage 12 and the combustion chamber. The intake and exhaust valves 13 and 14 are opened and closed by intake and exhaust camshafts 15 and 16 to which the rotation of the crankshaft 5 is transmitted via a timing chain or the like.

  In this example, a cam position sensor 302 that generates a pulse signal when the piston 3 of a specific cylinder 2 reaches the compression top dead center is provided in the vicinity of the intake camshaft 15. The cam position sensor 302 is composed of, for example, an electromagnetic pickup, and outputs a pulse signal along with the rotation of the rotor provided on the intake camshaft 15, similarly to the crank position sensor 301.

Further, a catalyst 17 made of a three-way catalyst, for example, is disposed in the exhaust passage 12 downstream of the exhaust manifold 12b. In this catalyst 17, CO and HC in the exhaust gas exhausted from the combustion chamber in the cylinder 2 to the exhaust passage 12 are oxidized and NOx is reduced, and these are harmless CO ₂ , H ₂ O, N _2. By doing so, the exhaust gas can be purified.

In this example, an exhaust temperature sensor 308 and an air-fuel ratio (A / F) sensor 309 are disposed in the exhaust passage 12 upstream of the catalyst 17, and an O ₂ sensor 310 is disposed in the exhaust passage 12 downstream of the catalyst 17. It is arranged.

-Fuel injection system-
Next, the fuel injection system of the engine 1 will be described.

  Each cylinder 2 of the engine 1 is provided with an in-cylinder injector 21 (first injection valve) so as to inject fuel directly into the combustion chamber. The in-cylinder injectors 21 of the four cylinders 2 are connected to a common high-pressure fuel delivery pipe 20. In addition, a port injection injector 22 (second injection valve) is disposed in the intake passage 11 of the engine 1 so as to inject fuel into each intake port 11a. Port injectors 22 are also provided in each of the four cylinders 2 and connected to a common low-pressure fuel delivery pipe 23.

  The fuel is supplied to the high-pressure fuel delivery pipe 20 and the low-pressure fuel delivery pipe 23 by a low-pressure pump 24 and a high-pressure pump 25 (hereinafter also simply referred to as fuel pumps 24 and 25), which are fuel pumps. The low pressure pump 24 pumps up the fuel in the fuel tank 26 and supplies it to the low pressure fuel delivery pipe 23 and the high pressure pump 25. The high-pressure pump 25 pressurizes the supplied low-pressure fuel to a high pressure equal to or higher than a predetermined level and supplies the pressurized high-pressure fuel to the delivery pipe 20 for high-pressure fuel.

  In this example, the high-pressure fuel delivery pipe 20 is provided with a high-pressure fuel fuel pressure sensor 311 (see FIG. 2) for detecting the pressure (fuel pressure) of the high-pressure fuel supplied to the in-cylinder injector 21. The fuel delivery pipe 23 is provided with a fuel pressure sensor 312 for low pressure fuel (see FIG. 2) for detecting the pressure (fuel pressure) of the low pressure fuel supplied to the port injector 22.

  The in-cylinder injector 21 and the port injector 22 are both electromagnetically driven actuators that open and inject fuel when a predetermined voltage is applied. The high pressure pump 25 and the low pressure pump 24 are actuators that supply fuel to the injectors 21 and 22. The operations of the injectors 21 and 22, that is, the number of times of fuel injection (injection mode), the timing of starting injection at each time, the injection amount at each time, and the discharge amounts and discharge pressures of the fuel pumps 24 and 25 will be described later. The ECU 500 is controlled.

  A mixture of air and fuel gas is formed in the combustion chamber in the cylinder 2 by fuel injection from one or both of the in-cylinder injector 21 and the port injector 22. The piston 3 is pushed down by the high-temperature and high-pressure combustion gas generated when this air-fuel mixture is ignited by the spark plug 6 and combusted / exploded to rotate the crankshaft 5. The combustion gas is discharged into the exhaust passage 12 as the exhaust valve 14 is opened, and becomes exhaust gas.

-ECU-
ECU 500 includes a CPU (Central Processing Unit) 501, a ROM (Read Only Memory) 502, a RAM (Random Access Memory) 503, a backup RAM 504, and the like, as schematically shown in FIG.

  The ROM 502 stores various control programs, maps that are referred to when the various control programs are executed, and the like. The CPU 501 executes various arithmetic processes based on various control programs and maps stored in the ROM 502. The RAM 503 is a memory that temporarily stores the calculation results of the CPU 501, data input from each sensor, and the like. The backup RAM 504 is a nonvolatile memory that stores data to be saved when the engine 1 is stopped, for example. Memory.

  The CPU 501, ROM 502, RAM 503, and backup RAM 504 are connected to each other via a bus 507, and are connected to an input interface 505 and an output interface 506.

The input interface 505 includes a crank position sensor 301, a cam position sensor 302, a water temperature sensor 303, an air flow meter 304, a throttle opening sensor 305, an accelerator opening sensor 306, an intake air temperature sensor 307, an exhaust gas temperature sensor 308, and an air-fuel ratio sensor 309. Various sensors such as an O ₂ sensor 310, a fuel pressure sensor 311 for high-pressure fuel, and a fuel pressure sensor 312 for low-pressure fuel are connected.

  An ignition switch 313 is also connected to the input interface 505. When the ignition switch 313 is turned on, cranking of the engine 1 by a starter motor (not shown) is started. On the other hand, the output interface 506 is connected to the igniter 7 of the spark plug 6, the throttle motor 8a of the throttle valve 8, the in-cylinder injector 21, the port injector 22, the low pressure pump 24, the high pressure pump 25, and the like. .

  The ECU 500 controls energization of the spark plug 6 by the igniter 7, drive control of the throttle valve 8 (throttle motor 8 a), injectors 21 and 22 based on the signals from the various sensors 301 to 312 and the switch 313. And various controls of the engine 1 including drive control of the pumps 24 and 25 are executed.

  Thus, the operation of the engine 1 is suitably controlled so that basic functional requirements such as drivability, exhaust gas, and fuel consumption are satisfied in a well-balanced manner. That is, the ECU 500 realizes requests related to various functions of the engine 1 by cooperative control of a plurality of actuators (igniter 7, throttle valve 8, injectors 21, 22, pumps 24, 25, etc.). An internal combustion engine control apparatus according to an embodiment of the present invention is realized by a control program executed by the ECU 500.

[Hierarchical structure of control devices]
Next, the configuration of the control device will be described in detail. In FIG. 3, each element of the control device is indicated by a block, and signal transmission between the blocks is indicated by an arrow. In this example, the control device has a hierarchical control structure including five hierarchies 510 to 550, the request generation hierarchy 510 at the highest level, and the physical quantity arbitration hierarchy 520 and the control quantity setting hierarchy 530 at the lower level. Further, a control amount arbitration hierarchy 540 is provided at the lower level, and a control output hierarchy 550 is provided at the lowest level.

  The signal flow is unidirectional between the five layers 510 to 550, from the highest request generation layer 510 to the lower physical quantity adjustment layer 520, from the physical quantity adjustment layer 520 to the lower control amount setting layer 530, and A signal is transmitted from the control amount setting layer 530 to the lower control amount adjustment layer 540. Although not shown, a common signal distribution system is provided that distributes a common signal in parallel to each of the layers 510 to 550 independently of the layers 510 to 550.

  There are the following differences between signals transmitted between the layers 510 to 550 and signals distributed by the common signal distribution system. A signal transmitted between the levels 510 to 550 is a signal obtained by converting a request regarding the function of the engine 1 and is finally converted into a control amount of the actuators 7, 8,. On the other hand, a signal distributed by the common signal distribution system is a signal including information necessary for generating a request and calculating a control amount.

  Specifically, the signal distributed by the common signal distribution system is information related to the operating condition and operating state of the engine 1 (engine speed, intake air amount, estimated torque, actual ignition timing, cooling water temperature, operating mode, etc. The information source is various sensors 301 to 312 provided in the engine 1, estimation functions inside the control device, and the like. Since these pieces of information are common engine information that is commonly used in each of the layers 510 to 550, if the information is distributed in parallel to each of the layers 510 to 550, not only can the communication amount between the layers 510 to 550 be reduced. The simultaneity of information between the layers 510 to 550 can be maintained.

-Request generation hierarchy-
Hereinafter, the configuration of each of the hierarchies 510 to 550 and the processing performed there will be described in order from the upper hierarchy. First, in the request generation hierarchy 510, a plurality of request output units 511 to 519 are arranged. The request here is a request related to the function of the engine 1 (it can be said that the performance is required for the engine 1), and the request output units 511 to 519 are provided for each function of the engine 1. The functions of the engine 1 are various, and the contents of the request output unit arranged in the request generation hierarchy 510 differ depending on what is required of the engine 1 and what is given priority.

  In the present embodiment, the engine 1 is driven efficiently according to the driving operation of the driver of the vehicle, and drivability, exhaust gas, and fuel consumption are satisfied in a well-balanced manner as basic functions in order to meet the demand for protection of the natural environment. This is the premise of control. For this reason, the request generation hierarchy 510 is first provided with a request output unit 511 corresponding to a function related to drivability, and a request output unit 512 corresponding to a function related to exhaust gas, and corresponding to a function related to fuel consumption. A request output unit 513 is provided.

  Further, in the present embodiment, in addition to the three basic function requests, there are basic injection function requests such as the number and timing of the injection operations of the injectors 21 and 22, respectively. Considering that there are various requirements that occur in specific conditions, such as fuel pressure reduction before C (fuel cut), rapid warm-up of catalyst 17, stratified combustion start (stratified start), idling stop S & S stop, etc. ing. Therefore, as shown in FIG. 3, the request generation hierarchy 510 is also provided with request output units 514 to 519 corresponding to the requests as described above, but the request output units 514 to 519 will be described in detail. It will be described later.

  The request output units 511 to 513 numerically output basic function requests such as drivability, exhaust gas, and fuel consumption of the engine 1. Since the control amount of the actuators 7, 8,... Is determined by calculation as described below, the request can be reflected in the control amount of the actuators 7, 8,. . In the present embodiment, the basic function request is expressed as a physical quantity related to the operation of the engine 1.

  As the physical quantity, only three kinds of torque, efficiency and air-fuel ratio are used. The output (in a broad sense) of the engine 1 can be mainly referred to as torque, heat, and exhaust gas (heat and components), and these outputs are related to the functions such as drivability, exhaust gas, and fuel consumption described above. And in order to control these outputs, it is only necessary to determine three physical quantities of torque, efficiency, and air-fuel ratio. Therefore, a request is expressed using these three physical quantities, and the operations of the actuators 7, 8,. By controlling, it is possible to reflect the request on the output of the engine 1.

  In FIG. 3, as an example, the request output unit 511 outputs a request regarding drivability (drivability request) as a request value expressed by torque or efficiency. For example, if the request is acceleration of the vehicle, the request can be expressed by torque. If the request is prevention of engine stall, the request can be expressed by efficiency (efficiency increase).

  Further, the request output unit 512 outputs a request regarding exhaust gas as a request value expressed in terms of efficiency and air-fuel ratio. For example, if the requirement is warming up of the catalyst 17, the requirement can be expressed by efficiency (efficiency reduction), and can also be expressed by air-fuel ratio. If the efficiency is reduced, the exhaust gas temperature can be increased, and if the air-fuel ratio is used, an atmosphere in which the reaction with the catalyst 17 is easy can be achieved.

  Further, the request output unit 513 outputs a request regarding fuel efficiency as a request value expressed in terms of efficiency and air-fuel ratio. For example, if the demand is an increase in combustion efficiency, the demand can be expressed by efficiency (increased efficiency). If the request is a reduction in pumping loss, the request can be expressed by an air-fuel ratio (lean burn).

  The request values output from the request output units 511 to 513 are not limited to one for each physical quantity. As an example, not only the required torque from the driver (torque calculated from the accelerator opening) but also VSC (Vehicle Stability Control system), TRC (Traction Control System), ABS (Antilock Brake System) Torques required from various devices for vehicle control such as transmission are also output at the same time. The same applies to efficiency.

  Common engine information is distributed to the request generation hierarchy 510 from the common signal distribution system. Each request output unit 511 to 513 determines a request value to be output with reference to the common engine information. This is because the content of the request varies depending on the operating condition and operating state of the engine 1. For example, when the catalyst temperature is measured by the exhaust temperature sensor 308, the request output unit 512 determines whether the catalyst 17 needs to be warmed up based on the temperature information, and determines the required efficiency value or air-fuel ratio according to the determination result. Output the requested value.

  As described above, the request output units 511 to 513 of the request generation hierarchy 510 output a plurality of requests expressed in torque, efficiency, or air-fuel ratio, and all these requests are realized simultaneously and completely. I can't do it. This is because only one torque can be realized even if there are a plurality of torque requests. Similarly, one efficiency can be realized for a plurality of efficiency requirements, and one air-fuel ratio can be realized for a plurality of air-fuel ratio requirements. For this reason, a process of request arbitration is required.

-Physical quantity arbitration hierarchy-
In the physical quantity arbitration hierarchy 520, the request value output from the request generation hierarchy 510 is arbitrated. In the physical quantity arbitration hierarchy 520, arbitration units 521 to 523 are provided for each physical quantity that is a classification of requests. The arbitration unit 521 aggregates the request values expressed by torque and arbitrates to one torque request value. The arbitration unit 522 aggregates the request values expressed by the efficiency and mediates to one efficiency request value. Then, the arbitrating unit 523 aggregates the required values expressed by the air-fuel ratio and adjusts to one air-fuel ratio required value.

  Each of these mediation units 521 to 523 performs mediation according to a predetermined rule. The rule here is a calculation rule for obtaining one numerical value from a plurality of numerical values, for example, maximum value selection, minimum value selection, average, or superposition, and the plurality of calculation rules are appropriately combined. It can also be. However, it is up to the design to decide what rule, and the content of the rule is not limited in the present invention. The common engine information is also distributed from the common signal distribution system to the physical quantity arbitration hierarchy 520, and the common engine information can be used in each of the arbitration units 521 to 523.

  In the arbitration units 521 to 523, the upper limit torque and the lower limit torque that can be actually realized by the engine 1 are not considered in the arbitration. Further, the arbitration results of the other arbitration units 521 to 523 are not taken into account in the arbitration. That is, each of the arbitration units 521 to 523 performs arbitration without considering the upper and lower limits of the feasible range of the engine 1 and the arbitration results of other arbitration units. This also contributes to a reduction in control calculation load.

  As described above, arbitration is performed in each of the arbitration units 521 to 523, so that one torque request value, one efficiency request value, and one air-fuel ratio request value are output from the physical quantity arbitration hierarchy 520. . In the control amount setting layer 530, which is a lower layer, control amounts of the actuators 7, 8,... Are set based on the arbitrated torque request value, efficiency request value, and air-fuel ratio request value.

-Control amount setting hierarchy-
In the present embodiment, one adjustment conversion unit 531 is provided in the control amount setting hierarchy 530, and first, the magnitudes of the torque request value, the efficiency request value, and the air-fuel ratio request value adjusted in the physical quantity adjustment hierarchy 520 are adjusted. . As described above, in the physical quantity arbitration hierarchy 520, the feasible range of the engine 1 is not taken into account for the arbitration, and therefore there is a possibility that the engine 1 cannot be properly operated depending on the size of each required value. Therefore, the adjustment conversion unit 531 adjusts each required value based on the mutual relationship so that the engine 1 can be properly operated.

  In a hierarchy higher than the control amount setting hierarchy 530, the required torque value, the required efficiency value, and the required air-fuel ratio value are calculated independently, and the calculated values are mutually used and referenced among the elements involved in the calculation. It never happened. That is, for the first time in the control amount setting hierarchy 530, the torque request value, the efficiency request value, and the air-fuel ratio request value are referred to each other. Since the target of adjustment is limited to the required torque value, the required efficiency value, and the required air-fuel ratio value, the calculation load required for the adjustment can be reduced.

  How to perform the adjustment is left to the design, and the content of the adjustment is not limited in the present invention. However, if there is a priority among the torque request value, the efficiency request value, and the air-fuel ratio request value, it is preferable to adjust (correct) the request value having a lower priority. For example, a request value with a high priority is reflected as much as possible in the control amount of the actuators 7, 8,..., And a request value with a low priority is adjusted and reflected in the control amount of the actuators 7, 8,.

  By so doing, it is possible to achieve a certain degree of requests with low priority while sufficiently realizing requests with high priority within a range where the engine 1 can be operated properly. As an example, when the torque request value has the highest priority, the efficiency request value and the air-fuel ratio request value are corrected, and the correction degree with the lower priority is increased. If the priority order changes depending on the operating conditions of the engine 1, etc., the priority order may be determined based on the common engine information distributed from the common signal distribution system, and which request value should be corrected.

  Further, in the control amount setting hierarchy 530, a new signal is generated using the request value input from the physical quantity arbitration hierarchy 520 and the common engine information distributed from the common signal distribution system. For example, a ratio between the torque request value adjusted by the arbitration unit 521 and the estimated torque included in the common engine information is calculated by a division unit (not shown). The estimated torque is a torque that is output when the ignition timing is MBT based on the current intake air amount and air-fuel ratio. The calculation of the estimated torque is performed by another task of the control device.

  Although detailed explanation is omitted, when the priority order of the torque request value is highest as described above, the torque request value, the corrected efficiency request value, and the correction are corrected in the control amount setting hierarchy 530 as a result of the above processing. The required air-fuel ratio value and torque efficiency are calculated. Of these signals, the throttle opening is calculated (converted) from the torque request value and the corrected efficiency request value, and transmitted to the control amount arbitration hierarchy 540.

  Specifically, first, the torque request value is divided by the corrected efficiency request value. Since the corrected efficiency requirement value is a value of 1 or less, if the torque requirement value is divided by this, the torque requirement value is raised. The torque demand value thus raised is converted into an air amount, and the throttle opening is calculated from the air amount. Note that the conversion of the torque request value into the air amount and the calculation of the throttle opening from the air amount are performed with reference to a preset map.

  The ignition timing is calculated (converted) mainly from torque efficiency. At this time, the torque request value and the corrected air-fuel ratio request value are also used as reference signals. Specifically, the retard amount with respect to MBT is calculated with reference to the map from the torque efficiency. The smaller the torque efficiency, the larger the retard amount, and as a result, the torque is reduced. The raising of the torque request value is a process for compensating for torque reduction due to retardation.

  In the present embodiment, both the required torque value and the required efficiency value can be realized by retarding the ignition timing based on the torque efficiency and increasing the required torque value based on the required efficiency value. The torque request value and the corrected air-fuel ratio request value are used for selecting a map for converting torque efficiency into a retard amount. Then, the final ignition timing is calculated from the retard amount and MBT (or basic ignition timing).

  As a result of the above processing, in the present embodiment, the signal transmitted from the control amount setting hierarchy 530 (adjustment conversion unit 531) to the control amount adjustment hierarchy 540 is a throttle opening request value (first value corresponding to the torque request). Demand value), ignition timing demand value and air-fuel ratio demand value. These signals are respectively input to the arbitration units 541, 542, and 543 of the control amount arbitration hierarchy 540 and are arbitrated together with other request values directly transmitted from the request generation hierarchy 510, as will be described in detail later.

-Control amount arbitration hierarchy-
As an example, as shown in FIG. 3, the control amount arbitration hierarchy 540 is provided with arbitration units 541 to 543 (543a to 543i) corresponding to the control amounts of the actuators 7, 8,. In the example shown in the figure, the arbitration unit 541 aggregates the required values of the throttle opening to adjust to one required value. Further, the arbitrating unit 542 aggregates the required values of the ignition timing and adjusts to one required value.

  Further, the arbitrating unit 543 arbitrates collectively the request values for a plurality of control amounts related to fuel injection. In the illustrated example, the arbitration unit 543 includes first to seventh arbitration units 543a to 543g that arbitrate the seven injection control amounts representing the operations of the injectors 21 and 22, respectively, and the discharge amount (pump control amount) of the low-pressure pump 24. This is an injection function arbitration unit in which an eighth arbitration unit 543h that arbitrates and a ninth arbitration unit 543i that arbitrates the discharge pressure (pump control amount) of the high-pressure pump 25 are integrally combined.

  In this way, the injection function arbitration unit 543 performs, for example, the same processing of the control program in order to integrally coordinate a plurality of control amounts related to a plurality of actuators such as the injectors 21 and 22, the low pressure pump 24, and the high pressure pump 25. In the step, the functions of the nine arbitration units 543a to 543i are realized. In this way, it is possible to ensure the synchronism of the control amounts of the injectors 21 and 22 and the fuel pumps 24 and 25.

  Each of the mediation units 541 to 543 (543a to 543i) performs mediation according to a predetermined rule, similarly to the mediation units 521 to 523 of the physical quantity arbitration hierarchy 520. The rules are left to the design, and the contents of the rules are not limited for the present invention. The common engine information is also distributed from the common signal distribution system to the control amount arbitration hierarchy 540, and the common engine information can be used in each of the arbitration units 541 to 543.

  Each of the above arbitration units 541 to 543 (543a to 543i) arbitrates various requests. From the control amount arbitration hierarchy 540, required values of control amounts of the individual actuators 7, 8,. Required value, ignition timing required value, required values for seven injection control amounts to be described later relating to the operation of the injectors 21 and 22, the discharge amount of the low-pressure pump 24 and the discharge pressure of the high-pressure pump 25, that is, two pump controls The requested quantity value is output.

-Control output hierarchy-
In the control output layer 550, which is a lower layer of the control amount arbitration layer 540, the control outputs of the actuators 7, 8,... Are calculated from the request values arbitrated as described above. In the illustrated example, the lowest control output layer 550 is provided with control output units 551 to 555 corresponding to signals transmitted from the control amount arbitration layer 540. A throttle opening request value is transmitted to the control output unit 551 (throttle drive control unit) from the throttle opening request value arbitration unit 541, and a throttle drive signal is output in response thereto.

  The control output unit 552 (igniter energization control unit) receives the ignition timing request value from the ignition timing request value arbitration unit 542 of the control amount arbitration hierarchy 540, and an igniter energization signal is output accordingly. The The control output unit 553 (an injector drive control unit that is an injection valve drive control unit) receives the required value of the injection control amount from the first to seventh arbitration units 543a to 543g of the injection function arbitration unit 543, In response to this, an injector drive signal is output.

  Further, the control output unit 554 (low pressure pump drive control unit) receives the required value of the fuel discharge amount from the eighth arbitration unit 543h of the injection function arbitration unit 543, and outputs a low pressure pump drive signal in response thereto. Is done. The control output unit 555 (high-pressure pump drive control unit) receives the required value of the fuel discharge pressure from the ninth arbitration unit 543i of the injection function arbitration unit 543, and outputs a high-pressure pump drive signal accordingly. .

  When generating the throttle drive signal in the control output unit 551, generating the igniter energization signal in the control output unit 552, and generating the low pressure pump and the high pressure pump drive signal in the control output units 554 and 555, the control output unit 553 The required value of the injection mode to be described later is referred to among the required values of the injection control amount to be transmitted, and the engine 1 is in a specific state such as stratified start or rapid catalyst warm-up based on the number of identifications included therein. Is identified.

-Mediation of injection function requirements-
In the following, with regard to the control amount arbitration of the actuator in the control amount arbitration hierarchy 540 described above, in particular, with regard to the arbitration of the injection function request, which is a feature of the present embodiment, with reference to FIGS. explain.

  First, as described above, in the control device of the present embodiment, the basic functional requirements of the engine 1 such as drivability, exhaust gas, and fuel consumption are expressed by a combination of three physical quantities such as torque, efficiency, and air-fuel ratio. Arbitration is performed at the level 520, but the number of times of fuel injection, the injection timing of each time, the injection ratio (the ratio of the injection amount), etc. are aspects of the operation of the injectors 21 and 22, so this is temporarily set to torque. If the control amount is calculated again after conversion to a physical quantity such as efficiency and physical quantity, an extra calculation load is generated.

  Therefore, in the present embodiment, as described above, the control amount arbitration layer 540 is provided below the control amount setting layer 530 so that the required value of the injection control amount related to the operation of the injectors 21 and 22 does not pass through the physical amount arbitration layer 520. To be communicated to the mediator. Although a detailed description is omitted, in the present embodiment, the requested value of the pump control amount related to the operation of the fuel pumps 24 and 25 is also arbitrated in the control amount arbitration hierarchy 540 in the same manner.

  First, as shown in FIG. 3, the request generation hierarchy 510 is provided with a request output unit 514 that outputs a request for a basic injection function that is necessary to appropriately operate the engine 1. Request output units 515 to 519 for outputting high-priority function requests, such as F / C pre-fuel pressure reduction, rapid catalyst warm-up, stratification start, S & S stop, and injector protection, are also provided as necessary.

  These request output units 514 to 519 each output a request not as a physical quantity but as a request value expressed by a control amount of the actuators 7, 8,..., And as shown in FIG. The information is directly transmitted to the control amount arbitration hierarchy 540 without going through the hierarchy 530. These required values are aggregated for each control amount together with the throttle opening, ignition timing, and air-fuel ratio required values transmitted from the control amount setting level 530 to the control amount arbitration level 540 as described above. The arbitration units 541 to 543 of the quantity arbitration hierarchy 540 arbitrate to one required value for each control amount.

  Specifically, a signal from the request output unit 514 of the basic injection function of the request generation hierarchy 510 is expressed by seven injection control amounts as will be described in detail later with reference to FIG. To the injection function arbitration unit 543 (543b to 543d and the like which will be described later with reference to FIG. 4). For example, the basic injection function request includes the number of fuel injections (injection mode) by each of the two injectors 21 and 22, the injection timing of each time, the injection ratio, and the like.

  As an example, from the basic injection request output unit 514a (see FIG. 4), in a predetermined operation region on the high load side of the engine 1, so-called multi-injection (cylinder injection) is performed in order to improve fuel spray dispersibility and reduce fuel consumption. The injectors 21 and 22 for both the internal injection and the port injection are operated to output a required value such as an injection timing for fuel injection performed in a plurality of times during one combustion cycle.

  In the present embodiment, the request output unit 514 includes request output units 514b to 514d that output fuel increase requests for parts protection, knock prevention, and the like. As will be described in detail later, the demand for the fuel to increase but the injection mode etc. is not changed is more combustible than the request to change the injection mode, such as the rapid catalyst warm-up described below. Therefore, it is included in the request output unit 514 of the basic injection function.

  Similar to the signal from the request output unit 514, the signal from the request output unit 515 for reducing the fuel pressure before F / C (fuel cut) is also transmitted to the injection function arbitration unit 543. This is because the fuel cut in advance is performed so that the temperature of the fuel in the high-pressure fuel delivery pipe 20 does not rise and the pressure (fuel pressure) becomes too high while the fuel cut control of the engine 1 is being performed. Immediately before starting the control, the in-cylinder injector 21 is operated to inject a small amount of fuel. For this purpose, a request value signal for operating the in-cylinder injector 21 is output from the request output unit 515 and transmitted to the arbitration unit 543 of the control amount arbitration hierarchy 540.

  On the other hand, signals from the demand output unit 516 for rapid catalyst warm-up and the request output unit 517 for stratification start are respectively adjusted for the throttle opening request value arbitration unit 541 and the ignition timing request value arbitration. Is transmitted to the unit 542 and the injection function arbitration unit 543. The rapid warm-up of the catalyst 17 is to perform a special control for maximizing the exhaust temperature in order to warm up the catalyst 17 in the shortest time after the cold start of the engine 1 or the like.

  Specifically, for example, the ignition timing is retarded until after TDC in order to raise the temperature of the exhaust gas, and the throttle valve 8 is opened to increase the air amount, thereby increasing the exhaust heat amount as much as possible. Further, the fuel injection timing in the compression stroke is retarded to increase the mixture concentration around the spark plug 6. Therefore, the request output unit 516 outputs signals of a request value for increasing the throttle opening, a request value for ignition retard, a request value for compression stroke injection, and a request value for increasing fuel pressure.

  The stratified start is a control that starts in a stratified combustion state in order to achieve both a shortening of the start time and a smooth start of engine rotation, and fuel is generated in the compression stroke of the cylinder 2 by the in-cylinder injector 21. (The fuel may also be injected from the port injector 22). For this purpose, the request output unit 517 outputs signals of the required value for the compression stroke injection and the required value for increasing the fuel pressure, together with the required values for the throttle opening and the ignition delay.

  Further, a signal from the S & S stop request output unit 518 is also transmitted to the arbitration units 541 to 543. The S & S stop is an idling stop control that automatically stops the operation of the engine 1 under a predetermined condition when the vehicle is stopped. The request output unit 518 suppresses vibration when the engine 1 is stopped. A request value for closing the throttle, a request value for stopping ignition, and a request value for stopping the operation of the fuel injection and the low-pressure pump 24 are output.

  The signal from the injector protection request output unit 519 is transmitted only to the arbitration unit 543. In this example, specifically, the fuel pressure (fuel pressure) in the high-pressure fuel delivery pipe 20 is reduced in order to protect the O-ring of the in-cylinder injector 21 as a demand for protecting the injector. The request output unit 519 outputs a request value for reducing the discharge pressure of the high-pressure pump 25.

  In this embodiment, as described above, priorities are set in advance for the signals from the request output units 514 to 519 transmitted to the control amount arbitration hierarchy 540 without going through the physical quantity arbitration hierarchy 520. As will be described, arbitration is performed based on the priority order. The specific priority is left to the design and is not particularly limited. For example, the request from the request output units 515 to 519 is set to have a higher priority than the request for the basic injection function from the request output unit 514. Has been.

-Mediation of injection control amount-
Hereinafter, with reference to FIGS. 4 and 5, the adjustment of the injection control amount in the injection function arbitration unit 543 will be described in detail. As described above, in the injection function arbitration unit 543, the operations of the first to seventh arbitration units 543a to 543g for arbitrating the seven injection control amounts representing the operations of the injectors 21 and 22 and the operations of the fuel pumps 24 and 25 are performed. Eighth and ninth arbiter 543h and 543i for adjusting the pump control amount to be expressed are provided, and the injection control amount and the pump control amount are adjusted together.

  The first arbitration unit 543a mediates the injection mode, that is, the number of fuel injections by the injectors 21 and 22, as one of the injection control amounts. Specifically, the first arbitration unit 543a has an injection mode corresponding to each request of the request output units 515 to 518 of the request generation hierarchy 510, that is, fuel pressure reduction, rapid catalyst warm-up, stratified start, and S & S stop. As a result, a three-digit numerical signal consisting of the number of injections of each of the injectors 21 and 22 and the identification number indicating the priority of each request is transmitted.

  Although the details of the three-digit numerical value of this injection mode will be described later, as an example, in order to rapidly warm up the catalyst, the in-cylinder injector 21 and the port injector 22 are once in one combustion cycle. When two injections are performed, the number of port injections is “1”, the number of in-cylinder injections is “1”, and the rapid catalyst warm-up identification number is “2”. A three-digit numerical value (112) is transmitted.

  The identification number in the third digit identifies the control corresponding to the request value of the injection mode and represents the priority of the request. As will be described later with reference to Table 1, the request output unit 515 Priorities are set in advance for each of the signal requests from ˜518, and the arbitration unit 543a selects the request value of one of the signals with the highest priority when any signal is input. (Mediation). However, the request value is not limited, and the request value can be calculated by a weighted average or the like so that the request value having a low priority is reflected while the request value having a high priority is heavily weighted.

  Further, in the present embodiment, in order to simplify the control process, a request value signal of the injection mode is not transmitted from the request output unit 514 of the basic injection function. As an example, the injection mode corresponding to the request for the basic injection function includes the number of port injections “1”, the number of in-cylinder injections “0”, and normal operation (the so-called rating of the engine 1 that is the most frequently used in normal vehicles). The three-digit numerical value (101) of the identification number “1” of the operation state) is set in advance in the injection function arbitration unit 543 as the basic mode.

  Similar to the first arbitration unit 543a, the second arbitration unit 543b arbitrates the fuel injection timing (injection start timing) of each of the injectors 21 and 22 as one of the injection control amounts. The second arbitration unit 543b includes request values for injection timing corresponding to the respective requests for basic injection, rapid catalyst warm-up, and stratified start from the request output units 514 (514a), 516, and 517 of the request generation hierarchy 510. As a result, a signal of a required value indicating the injection start timing of each of the injectors 21 and 22 is transmitted.

  For example, as described above, if the in-cylinder injector 21 is performed once and the port injector 22 is performed once, if two injection operations are performed, the start timing of each injection operation is A signal of a required value expressed by a corner is transmitted. Then, arbitration is performed according to a predetermined rule in the same manner as the first arbitration unit 543a. In addition, since the required value of the injection timing is assigned in order to each injection operation represented in the injection mode, it is not necessary to distinguish between the in-cylinder injector 21 and the port injector 22.

  The third arbitration unit 543c mediates the fuel injection amount by each of the injectors 21 and 22 when the engine 1 is started as one of the injection control amounts. The third arbitration unit 543c receives a request value signal indicating the fuel injection amount of each time corresponding to the injection request for basic injection and stratified start from the request output units 514 (514a) and 517 of the request generation hierarchy 510, respectively. Is transmitted.

  For example, in order to start stratification, the in-cylinder injector 21 is once and the port injector 22 is once. If two injection operations are performed, a required value indicating the injection amount of each injection The signal is transmitted. When starting in a uniform combustion state in a cold district or the like, the required value of the fuel injection amount for one injection by the port injector 22 is transmitted. Then, arbitration is performed according to a predetermined rule in the same manner as the first and second arbitration units 543a and 543b.

  The reason why the fuel injection amount at the time of starting is adjusted separately from the operating state in this manner is that the amount of air filling the cylinder 2 cannot be accurately calculated at the time of starting. While the engine 1 is in operation, the fuel injection amount is calculated from the air filling amount and the target air-fuel ratio as will be described later. However, since the air filling amount cannot be accurately calculated at the time of starting, the fuel injection amount has a value that is adapted in advance. Must be set. Therefore, a fuel injection amount that matches the state of the engine 1 at the time of starting, such as starting with stratified combustion or starting with uniform combustion, is set in advance, and is selected (arbitrated) from among them.

  The fourth arbitration unit 543d performs arbitration on a reference value for determining completion of the start control as one of the injection control amounts. The fourth arbitration unit 543d receives a signal of a determination value for determining the completion of starting in each of the uniform combustion start and the stratified start from the request output units 514 (514a) and 517 of the request generation hierarchy 510. The Then, arbitration is performed according to a predetermined rule.

  For example, in the case of starting with uniform combustion by basic injection, it is determined that the start is complete when the engine speed exceeds a preset engine speed (determination speed), but in the case of stratified start, the torque generated is compared. Since the engine speed is small, selection (arbitration) of the determination rotational speed is performed so that the start completion is determined after the engine rotational speed is higher. Further, in the case of a hybrid vehicle, the engine may be started while running with an electric motor. Therefore, it may be determined that the start is completed after a higher rotational speed.

  That is, when the engine is started while running with an electric motor in a hybrid vehicle, the engine speed may already be higher than the normal starting determination speed at the start of the start control. In this case, if it is determined that the start is completed at the normal determination rotation speed, the fuel injection amount after the start is adopted at the same time as the start of the start control, and an excessive amount is actually applied to the cylinder which has not been injected once. This is because fuel may be injected.

  The fifth arbitration unit 543e mediates, as one of the injection control amounts, the ratio of the fuel injection amount by each of the injectors 21 and 22 during the operation of the engine 1, that is, the injection division rate. The fifth arbitration unit 543e receives each of the injections 21 and 22 from the request output units 516 and 517 of the request generation hierarchy 510 as the required values of the injection ratio corresponding to the requests for rapid catalyst warm-up and stratification start. A request value signal representing the injection ratio is transmitted.

  As an example, if the in-cylinder injector 21 is performed twice and the port injector 22 is operated once, if the injection operation is performed three times, the port injection is performed once in the cylinder in the order of the injection operation. The required values of the respective injection ratios (for example, 40% and 40%) with the first injection are transmitted and selected (arbitration) according to a predetermined rule.

  The remaining injection ratio (for example, 20%) is assigned for the second in-cylinder injection. Further, in the present embodiment, a request value signal for the injection ratio is not transmitted from the request output unit 514 of the basic injection function. As the injection ratio corresponding to the basic injection function request, a basic value (ie, 100%) corresponding to one port injection in the basic mode is stored in advance in the injection function arbitration unit 543 as shown in FIG. .

  The sixth arbitration unit 543f arbitrates a correction coefficient for the total fuel injection amount as one of the injection control amounts. In other words, in the present embodiment, the required output of the fuel injection correction coefficient for parts protection, knock prevention and correction of the uncontributed portion is output to the required output unit 514 of the basic injection function in addition to the basic injection request. Portions 514b to 514d are included. These request values (signals) are transmitted to the increase pre-arbitration unit 543j and selected (pre-arbitration) according to a predetermined rule.

  The required value of the injection amount correction coefficient that is pre-adjusted in this way and output from the increase pre-adjustment unit 543j is transmitted to the sixth adjustment unit 543f. On the other hand, in the example of FIG. The required value of the injection amount correction coefficient for the machine is transmitted to the sixth arbitration unit 543f and arbitrated according to a predetermined rule. The reason for arbitrating in this way is that the logic suitable for each arbitration is different.

  That is, a request for pre-arbitration (first type request) such as parts protection and knock prevention is a request that changes the total fuel injection amount but does not change the injection mode, etc. This requirement (second type requirement) changes not only the total fuel injection amount but also the injection mode, and thus has a great influence on the combustibility of the air-fuel mixture in the cylinder 2. Therefore, as described above, after the injection amount correction coefficient is adjusted by the logic suitable for the first type of request in the increase pre-arbitration unit 543j, the injection is performed by the logic suitable for the second type of request by the sixth arbitration unit 543f. The amount correction coefficient is adjusted.

  The seventh arbitration unit 543g arbitrates the upper limit value when the fuel is injected in the compression stroke of the cylinder 2 by the in-cylinder injector 21, that is, the compression injection upper limit value, as one of the injection control amounts. That is, if the fuel injection amount in the compression stroke of the cylinder 2 becomes too large, the concentration deviation of the air-fuel mixture becomes large. For example, the surroundings of the spark plug may become excessively rich and the combustion state may deteriorate.

  Therefore, as an example, a signal for the upper limit value of the fuel injection amount in the compression stroke by the in-cylinder injector 21 during the rapid catalyst warm-up control is transmitted to the seventh arbitration unit 543g from the request output unit 516, and From the request output unit 517, a signal of the upper limit value of the fuel injection amount in the compression stroke at the time of stratification start is transmitted. Then, selection (arbitration) is performed according to a predetermined rule.

  In the present embodiment, the signal for the upper limit value of the fuel injection amount in the compression stroke is not transmitted from the request output unit 514 of the basic injection function. This is because the injection mode corresponding to the request for the basic injection function is the basic mode, and fuel injection by the in-cylinder injector 21 is not performed. As shown in FIG. 4, a basic value (maximum value) is stored in advance in the injection function arbitration unit 543 for convenience.

  As described above, the injectors 21 and 22 are suitable for various requirements during operation and start of the engine 1 by maintaining the simultaneity of the seven injection control amounts, in other words, by adjusting the injection control amounts in association with each other. Can be realized. The first to seventh arbitration units 543a to 543g constitute an injection control arbitration unit that arbitrates an injection control amount related to the operation of the injectors 21 and 22.

  Signals from the first to seventh arbitration units 543a to 543g are transmitted to the control output unit 553 (injector drive control unit) of the control output layer 550, as shown in FIG. The control output unit 553 includes an injection amount calculation unit 553a that calculates the fuel injection amount of each of the injectors 21 and 22, and a required value of the injection mode from the first arbitration unit 543a of the injection function arbitration unit 543. And the required value of the injection timing from the second arbitration unit 543b is transmitted, and the respective injection amounts of the injection operation defined in the injection mode are calculated.

  That is, the injection amount calculation unit 553a receives the injection distribution ratio, the injection amount correction coefficient, and the compression injection upper limit request values from the fifth to seventh arbitration units 543e to 543g of the injection function arbitration unit 543, respectively. The fuel injection amount from the target value of the fuel ratio (the stoichiometric air-fuel ratio is set in advance as a basic value), the amount of air filled into the cylinder 2 (included in the common engine information), and the injection ratio Is calculated. Further, the injection amount calculation unit 553a corrects the fuel injection amount by multiplying by an injection amount correction coefficient, and limits the injection amount to an upper limit value for the injection operation in the compression stroke.

  The required value of the fuel injection amount thus calculated and the required value of the fuel injection amount at the time of start-up from the third arbitration unit 543c of the injection function arbitration unit 543 are the injection amount selection unit 553b of the control output unit 553. And any required value is selected. That is, a start completion determination value (for example, engine speed) from the fourth arbitration unit 543d of the injection function arbitration unit 543 is transmitted to the injection amount selection unit 553b, and this is included in the actual engine revolution number (common engine information). If so, the fuel injection amount at the start is selected. On the other hand, if the actual engine speed is equal to or higher than the start completion determination value, the fuel injection amount calculated by the injection amount calculation unit 553a as described above is selected.

  The required value of the fuel injection amount thus selected, the current fuel pressure (the fuel pressure of the delivery pipe 20 for high pressure fuel and the delivery pipe for low pressure fuel 23 included in the common engine information), and the flow coefficient of each injector 21, 22 Based on the above, the injection pulse calculation unit 553c calculates the fuel injection period of each time by each of the injectors 21 and 22, that is, the injection pulse width. An injection signal (injector drive signal) having a pulse width calculated in this way is output to the injectors 21 and 22.

-Injection mode-
Hereinafter, a method of expressing the injection mode in the first arbitration unit 543a of the injection function arbitration unit 543 will be described in detail. As described above, the injection function arbitration unit 543 arbitrates the seven injection control amounts related to the operation of the injectors 21 and 22 and outputs them as a unit to the control output layer 550. When trying to mediate all the various requests related to the operation of the injectors 21 and 22 together, the logic becomes very complex, so the mediation was divided into injection modes (number of injections), injection timing, injection ratio, etc. It is output as a unit on top.

  Here, the fuel injected into the intake port 11 a by the port injection injector 22 is mixed with air in advance and sucked into the cylinder 2, while being directly injected into the cylinder 2 by the in-cylinder injector 21. The fuel spray forms an air-fuel mixture having a high concentration while diffusing in the combustion chamber. In this way, the process in which the injected fuel forms the air-fuel mixture is greatly different, so how many times the injectors 21 and 22 inject the fuel greatly affects the air-fuel mixture distribution and its combustibility. Become.

  In other words, the number of fuel injections has a great influence on the combustibility of the air-fuel mixture, in other words, the operating state of the engine 1 among various injection control amounts such as the injection timing and the injection ratio. The number of injections of each of the in-cylinder injector 21 and the port injector 22 is used as a control amount representing an aspect, that is, an injection mode.

  Further, in a specific state such as stratification start of the engine 1 or rapid warm-up of the catalyst 17, the injection control different from that during normal operation is required, and at the same time, control such as throttle and ignition is also performed during normal operation. There are different requirements. Therefore, in such a specific state, in order to synchronize the control of the injectors 21 and 22 with the control of the throttle valve 8 and the igniter 7, it is necessary to ensure the simultaneity of those controls.

  For this reason, in the present embodiment, as the injection mode, in addition to the number of injections of each of the injectors 21 and 22, a three-digit numerical value including the identification number indicating that the engine 1 is in a specific state is adopted. . Specifically, as shown in Table 1 below, for example, when fuel injection is stopped in response to a request such as S & S stop, if the number of identifications in a specific case of “stop” is “0”, the injection mode The required value is (000).

  Further, the basic injection function request in the normal operation state of the engine 1 is a basic mode in which only the port injection injector 22 is injected once (port 1 injection), and the identification number is “1”. As shown in 1, the required value is (101). Even in a normal operation state, only the in-cylinder injector 21 is required to inject once (in-cylinder injection), the required value is (011), and the in-cylinder and port injectors 21 and 22 are set to 1 In the case of multi-injection in which injection is performed one by one (one port + one in-cylinder injection), (111).

  Furthermore, even if the number of injections is the same, the required number is different because the number of identifications is different if the state of the engine 1 is different. For example, when performing multi-injection in response to a request for rapid warm-up of the catalyst 17, if the identification number of catalyst rapid warm-up is “2”, the required value for multi-injection for injecting the injectors 21 and 22 once is as follows: As shown in Table 1, (112) is obtained, and if only the in-cylinder injector 21 is to be injected twice, the required value is (022) (in-cylinder twice injection during rapid catalyst warm-up) ).

  If the identification number of the stratified start of the engine 1 is “3”, as shown in Table 1, the required value for in-cylinder one-time injection for stratified start is (013), and multi-injection (port The required value for one injection + one in-cylinder injection is (113), and the required value for two in-cylinder injection is (023). As described above, the injection mode can be expressed in a simple format by a three-digit numerical value composed of the number of injections of the two injectors 21 and 22 and the identification number in a specific case such as starting.

  In the control output unit 553 to which the requested value after arbitration is transmitted from the first arbitration unit 543a for the injection mode, a drive signal is generated based on at least the number of injections of each of the injectors 21 and 22. Good mixture formation corresponding to various requirements such as basic injection, stratification start-up, and rapid catalyst warm-up can be realized. Of course, for the actual drive signal generation, the arbitration results of other injection control amounts such as the injection timing and the injection distribution ratio are used as described above.

  Further, since it is possible to identify a specific state such as stratified start-up or rapid catalyst warm-up from the number of identifications, it becomes possible to ensure synchronism with throttle control and ignition control that should be coordinated with fuel injection control. . That is, when the throttle drive signal and the igniter energization signal are generated in the control output level 550, the required value of the injection mode is referred to, and the specific state of the engine 1 is identified from the identification number.

  As an example, when the catalyst is rapidly warmed up, fuel is injected by the in-cylinder injector 21 in the compression stroke of the cylinder 2, and the throttle opening is increased to retard the ignition timing. At this time, since it is identified that the catalyst is rapidly warmed up with reference to the identification number “2” included in the arbitration result of the injection mode, the control output units 551 and 552 of the control output level 550 are assumed to perform control calculation. Even if an error occurs, it is possible to prevent a mismatch between the generated throttle drive signal or igniter energization signal and the injector drive signal.

-Effects of the control device of this embodiment-
As described above, in the control device according to the present embodiment, first, the control output hierarchy is generated from the highest request generation hierarchy 510 in the hierarchical structure through the physical quantity arbitration hierarchy 520, control quantity setting hierarchy 530, and control quantity arbitration hierarchy 540. Since the signal is transmitted in one direction up to 550, the control calculation load can be reduced.

  In addition, the basic functional requirements of the engine 1 such as drivability, exhaust gas, and fuel consumption are expressed by a combination of three physical quantities of torque, efficiency, and air-fuel ratio, and arbitration is performed in the physical quantity arbitration hierarchy 520. The engine 1 can be operated in a suitable state that satisfies these basic requirements in a well-balanced manner.

  On the other hand, requests for fuel injection mode, stratification start-up, rapid catalyst warm-up, etc. are transmitted directly to the control amount arbitration hierarchy 540 without going through physical quantity arbitration, and in other words, the engine 1 By distributing the various requests related to the functions to the appropriate one of physical quantity arbitration and control quantity arbitration, all the various function requests can be realized appropriately without increasing the control computation load. be able to.

  Furthermore, the required value of the injection mode, which is one of the fuel injection control amounts (injection control amounts), is a three-digit numerical value consisting of the number of injections of each injector 21 and 22 and the identification number of a specific state of the engine 1. In the control output hierarchy 550 to which the required value is transmitted, suitable fuel injection control can be realized while ensuring simultaneity with other controls such as throttle and ignition.

  In addition, for example, in an engine that does not include the in-cylinder injector 21, it is only necessary to set the second digit of the three-digit value to zero (0), and the format of the injection mode of the three-digit value is changed. There is no need. Therefore, a common control program can be easily applied to engines with different specifications, and the number of changes in the control program can be reduced even when the specifications change.

-Other embodiments-
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, three basic functional requirements for the engine 1 are drivability, exhaust gas, and fuel consumption, and these are expressed by three physical quantities of torque, efficiency, and air-fuel ratio for mediation. However, it is not limited to this.

  In addition, the function request expressed by the control amount of the actuators 7, 8,... Instead of the above three physical amounts is also used for reducing the pre-F / C fuel pressure, stratified start, rapid catalyst warm-up, etc. It is not limited to the control. In addition, for example, there is cylinder deactivation control for deactivating some of the plurality of cylinders 2 of the engine 1, and various function requests such as fail-safe and OBD are also included.

  Further, the actuator of the engine 1 is not limited to the igniter 7, the throttle valve 8, the injectors 21 and 22, the fuel pumps 24 and 25, etc. of the above embodiment. For example, a variable valve timing device (VVT), a variable valve lift amount device (VVL), and an external EGR device can be used as actuators to be controlled. In an engine including a cylinder stop mechanism and a variable compression ratio mechanism, these mechanisms can also be controlled actuators.

  Furthermore, in the above-described embodiment, the case where the control device of the present invention is applied to the spark ignition engine 1 mounted on a vehicle has been described. However, the present invention is applicable to engines other than the spark ignition engine 1, for example, diesel engines. It can also be applied, and can also be applied to an engine provided in a hybrid system including an electric motor.

1 engine (internal combustion engine)
2 cylinder 7 igniter (actuator)
8 Throttle valve (actuator)
11a Intake port 21 In-cylinder injector (first injection valve, fuel injection valve: actuator)
22 Port injector (second injection valve, fuel injection valve: actuator)
24 Low pressure pump (fuel pump: actuator)
25 High-pressure pump (fuel pump: actuator)
500 ECU
510 Request Generation Hierarchy 520 Physical Quantity Arbitration Hierarchy 530 Control Amount Setting Hierarchy 540 Control Amount Arbitration Hierarchy 543 Injection Function Arbitration Units 543a to 543g 1st to 7th Arbitration Units (Injection Control Arbitration Units)

Claims (1)

A control device for an internal combustion engine that realizes requests related to various functions of the internal combustion engine by cooperatively controlling a plurality of actuators related to the operation of the internal combustion engine,
A request generation hierarchy for outputting a request value relating to the function of the internal combustion engine;
A physical quantity arbitration hierarchy that is provided at a lower level of the request generation hierarchy and aggregates and mediates what is expressed by a predetermined physical quantity among the request values;
A control amount setting layer provided at a lower level of the physical quantity arbitration layer, and setting a control amount of the actuator based on the arbitrated request value;
A hierarchical control structure in which a signal is transmitted in one direction from an upper hierarchy to a lower hierarchy in the order of the request generation hierarchy, physical quantity arbitration hierarchy, and control quantity setting hierarchy;
Further, below the control amount setting layer, the request value output from the request generation layer is expressed by the control amount of the actuator without being transmitted through the physical quantity arbitration layer. There is a control amount arbitration hierarchy that aggregates and mediates,
The plurality of actuators include a first injection valve arranged to inject fuel directly into the cylinder and a second injection valve arranged to inject fuel into the intake port of each cylinder. Included,
Wherein the control amount arbitration hierarchy, before Symbol least as injection control amount relating to the operation of the first and second injection valve, the injection frequency of the first and second injection valve, the injection timing, and the injection for arbitrating their injection ratio A control arbitration unit is provided,
The request value transmitted from the request generation hierarchy to the injection control arbitration unit without going through the physical quantity arbitration hierarchy is identified corresponding to each state when the internal combustion engine is in a plurality of specific states. The number of identifications to be performed and the number of injections of the first and second injection valves in each state include a three-digit numerical value represented by each digit, and a priority is set in advance for each state. Has been
The injection control arbitration unit arbitrates the number of injections of the first and second injection valves according to the priority order, separately from the injection timing and the injection ratio, and displays the arbitration result as the first and second injection valves. A control apparatus for an internal combustion engine, wherein the number of injections and the identification number are output as three-digit numerical values .

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