JP2012148702A - Control device, hybrid vehicle and control method, as well as program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the effect of friction of an electric motor during engine travel without deteriorating SOC.SOLUTION: A hybrid ECU 18 is constituted, for operating an engine 10 with the torque obtained by adding preset friction torque of an electric motor 13 corresponding to the rotation speed of an engine 10 to requested torque during the travel by the engine 10 and for performing the control so that the electric motor 13 generates the torque equivalent to the friction torque.

Description

  The present invention relates to a control device, a hybrid vehicle, a control method, and a program.

  The hybrid vehicle has an engine and an electric motor, and the engine or the electric motor, or the engine and the electric motor can run in cooperation with each other. Even when the engine is running, the rotating shaft of the electric motor is rotated by the output of the engine. It has been made.

While driving with such an engine, the state of charge of the battery (hereinafter referred to as SOC: State
In some cases, the electric motor operates as a generator driven by the engine and can charge the battery (this is called regeneration). On the other hand, when the SOC of the battery is good, since the motor is not operated as a generator, the motor is driven by the engine. At this time, in order to avoid that the electric motor becomes the friction of the engine, zero torque control is performed in which the electric motor is controlled so as to generate a torque for offsetting its own friction (see, for example, Patent Document 1).

JP 2009-196485 A

  In the above-described zero torque control, the electric motor consumes electric power in order to generate torque for offsetting its own friction. If this state continues for a long time, the SOC of the battery may deteriorate.

  The present invention has been made under such a background, and a control device, a hybrid vehicle, and a control method capable of eliminating the influence of the friction of the electric motor while the engine is running without deteriorating the SOC, The purpose is to provide a program.

  One aspect of the present invention is a viewpoint as a control device. The control device of the present invention includes an engine and an electric motor, and the engine or the electric motor, or the engine and the electric motor can travel in cooperation with each other. In the control apparatus for a hybrid vehicle rotated by the engine, the engine is operated with a torque obtained by adding the friction torque of the motor according to the preset engine rotation speed to the required torque while the engine is running. Control means for controlling to generate a torque corresponding to the friction torque is provided.

  At this time, it has a friction map in which the friction torque of the electric motor according to the preset engine speed is recorded, and the control means refers to the friction map to calculate the motor friction torque from the engine speed. Can be read.

  Another aspect of the present invention is a viewpoint as a hybrid vehicle. The hybrid vehicle of the present invention has the control device of the present invention.

  Still another aspect of the present invention is a viewpoint as a control method. The control method of the present invention includes an engine and an electric motor, and the engine or the electric motor, or the engine and the electric motor can run in cooperation, and during the running by the engine, the rotating shaft of the electric motor is output from the engine. In the control method executed by the control device of the hybrid vehicle rotated by the engine, the engine is operated with a torque obtained by adding the friction torque of the motor according to the preset engine rotation speed to the required torque while the engine is running. And a control step for controlling the electric motor to generate a torque corresponding to the friction torque.

  Still another aspect of the present invention is a viewpoint as a program. The program of the present invention causes an information processing device to realize the function of the control device of the present invention.

  According to the present invention, it is possible to eliminate the influence of the friction of the electric motor while the engine is running without deteriorating the SOC.

It is a block diagram showing an example of composition of a hybrid car of an embodiment of the invention. It is a block diagram which shows the example of a structure of the function implement | achieved in hybrid ECU of FIG. It is a flowchart which shows operation | movement of the torque control part of FIG.

  Hereinafter, a hybrid vehicle according to an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is a block diagram illustrating an example of the configuration of the hybrid vehicle 1. The hybrid vehicle 1 is an example of a vehicle. The hybrid vehicle 1 is driven by an engine (internal combustion engine) 10 and / or an electric motor 13 via a transmission of a semi-automatic transmission, and travels with the power of the engine 10 (this is referred to as an engine travel mode) via the clutch 12. The rotating shaft of the electric motor 13 and the rotating shaft of the engine 10 are connected. At this time, the electric motor 13 can be operated as a generator by the output of the engine 10. On the other hand, when the SOC of the battery 15 is good and the electric motor 13 does not need to generate electric power, the electric motor 13 does not generate electric power and is brought into a state of being driven by the engine 10. The following description relates to control when the electric motor 13 does not generate power and is driven by the engine 10. The semi-automatic transmission described above is a transmission that can automatically perform a shifting operation while having the same configuration as a manual transmission.

  The hybrid vehicle 1 includes an engine 10, an engine ECU (Electronic Control Unit) 11, a clutch 12, an electric motor 13, an inverter 14, a battery 15, a transmission 16, an electric motor ECU 17, a hybrid ECU 18 (control device in the claims), wheels 19, and keys. A switch 20 and a shift unit 21 are included. The transmission 16 has the above-described semi-automatic transmission and is operated by a shift unit 21 having a drive range (hereinafter referred to as a D (Drive) range). When the shift unit 21 is in the D range, the shifting operation of the semi-automatic transmission is automated.

  The engine 10 is an example of an internal combustion engine, and is controlled by an engine ECU 11 to burn gasoline, light oil, CNG (Compressed Natural Gas), LPG (Liquefied Petroleum Gas), or alternative fuel, and the like to rotate a rotating shaft. The generated power is generated, and the generated power is transmitted to the clutch 12.

  The engine ECU 11 is a computer that operates in cooperation with the electric motor ECU 17 by following instructions from the hybrid ECU 18 and controls the engine 10 such as the fuel injection amount and valve timing. For example, the engine ECU 11 includes a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), a microprocessor (microcomputer), a DSP (Digital Signal Processor), and the like. O (Input / Output) port and the like.

  The clutch 12 is controlled by the hybrid ECU 18 and transmits the shaft output from the engine 10 to the wheels 19 via the electric motor 13 and the transmission 16. That is, the clutch 12 mechanically connects the rotating shaft of the engine 10 and the rotating shaft of the electric motor 13 under the control of the hybrid ECU 18 to transmit the shaft output of the engine 10 to the electric motor 13, or By disconnecting the mechanical connection between the rotating shaft of the motor 10 and the rotating shaft of the electric motor 13, the rotating shaft of the engine 10 and the rotating shaft of the electric motor 13 can be rotated at different rotational speeds.

  For example, the clutch 12 causes the hybrid vehicle 1 to travel by the power of the engine 10, thereby causing the electric motor 13 to generate electric power, when the engine 10 is assisted by the driving force of the electric motor 13, and to start the engine 10 by the electric motor 13. In some cases, the rotating shaft of the engine 10 and the rotating shaft of the electric motor 13 are mechanically connected. Further, even in the engine running mode using only the power of the engine 10, the rotation shaft of the engine 10 and the rotation shaft of the motor 13 are connected by the clutch 12. In this engine running mode, the electric motor 13 is not operating as a generator and is being rotated by the engine 10.

  Further, for example, the clutch 12 is in a state where the engine 10 is stopped or idling and the hybrid vehicle 1 is running by the driving force of the electric motor 13 and when the engine 10 is stopped or idling and the hybrid vehicle 1 is decelerated. When traveling on a middle or downhill and the electric motor 13 is generating regenerative power, the mechanical connection between the rotating shaft of the engine 10 and the rotating shaft of the electric motor 13 is disconnected.

  The clutch 12 is different from the clutch that is operated by the driver operating the clutch pedal, and operates under the control of the hybrid ECU 18.

  The electric motor 13 is a so-called motor generator, which generates electric power for rotating the rotating shaft by the electric power supplied from the inverter 14 and supplies the shaft output to the transmission 16 or the rotation supplied from the transmission 16. Electricity is generated by the power that rotates the shaft, and the electric power is supplied to the inverter 14. For example, when the hybrid vehicle 1 is accelerating or traveling at a constant speed, the electric motor 13 generates power for rotating the rotating shaft, and supplies the shaft output to the transmission 16. The hybrid vehicle 1 is driven in cooperation with the vehicle. Further, for example, when the electric motor 13 is driven by the engine 10, or when the hybrid vehicle 1 is decelerating or traveling downhill, the electric motor 13 operates as a generator. In this case, the power is generated by the power that rotates the rotating shaft supplied from the transmission 16, the electric power is supplied to the inverter 14, and the battery 15 is charged. At this time, the electric motor 13 generates a regenerative torque having a magnitude corresponding to the regenerative power.

  The inverter 14 is controlled by the electric motor ECU 17 and converts the DC voltage from the battery 15 into an AC voltage or converts the AC voltage from the electric motor 13 into a DC voltage. When the electric motor 13 generates power, the inverter 14 converts the DC voltage of the battery 15 into an AC voltage and supplies electric power to the electric motor 13. When the electric motor 13 generates power, the inverter 14 converts the AC voltage from the electric motor 13 into a DC voltage. That is, in this case, the inverter 14 serves as a rectifier and a voltage regulator for supplying a DC voltage to the battery 15.

  The battery 15 is a chargeable / dischargeable secondary battery. When the electric motor 13 generates power, the electric power is supplied to the electric motor 13 via the inverter 14 or when the electric motor 13 is generating electric power, It is charged by the power it generates. An appropriate SOC range is determined for the battery 15, and the SOC is managed so that the SOC does not fall outside the range.

  The transmission 16 has a semi-automatic transmission (not shown) that selects one of a plurality of gear ratios (speed ratios) in accordance with a speed change instruction signal from the hybrid ECU 18. The power and / or power of the electric motor 13 is transmitted to the wheel 19. Further, the transmission 16 transmits the power from the wheels 19 to the electric motor 13 when decelerating or traveling downhill. In the semi-automatic transmission, the driver can manually change the gear position to an arbitrary gear stage by operating the shift unit 21.

  The electric motor ECU 17 is a computer that operates in cooperation with the engine ECU 11 according to an instruction from the hybrid ECU 18, and controls the electric motor 13 by controlling the inverter 14. For example, the electric motor ECU 17 is configured by a CPU, an ASIC, a microprocessor (microcomputer), a DSP, and the like, and has an arithmetic unit, a memory, an I / O port, and the like.

  The hybrid ECU 18 is an example of a computer, and for hybrid traveling, accelerator opening information, brake operation information, vehicle speed information, gear position information acquired from the transmission 16, engine rotation speed information acquired from the engine ECU 11, and a battery 15 The clutch 12 is controlled on the basis of the SOC information acquired from the control information, and the transmission 16 is controlled by supplying a shift instruction signal. The control instruction for the motor 13 and the inverter 14 is given to the motor ECU 17, and the engine ECU 11 is given control. The control instruction of the engine 10 is given. These control instructions include an engine torque control instruction and an electric motor torque control instruction which will be described later. For example, the hybrid ECU 18 includes a CPU, an ASIC, a microprocessor (microcomputer), a DSP, and the like, and has an arithmetic unit, a memory, an I / O port, and the like.

  The program executed by the hybrid ECU 18 can be installed in advance in the hybrid ECU 18 that is a computer by storing it in a nonvolatile memory inside the hybrid ECU 18 in advance.

  The engine ECU 11, the electric motor ECU 17, and the hybrid ECU 18 are connected to each other by a bus that conforms to a standard such as CAN (Control Area Network).

  The wheels 19 are driving wheels that transmit driving force to the road surface. Although only one wheel 19 is shown in FIG. 1, the hybrid vehicle 1 actually has a plurality of wheels 19.

  The key switch 20 is a switch that is turned on / off by a user, for example, when a key is started. When the key switch 20 is turned on, each part of the hybrid vehicle 1 is activated and the key switch 20 is turned off. Each part of the hybrid vehicle 1 is stopped by entering the state.

  As already described, the shift unit 21 gives an instruction from the driver to the semi-automatic transmission of the transmission 16, and when the shift unit 21 is in the D range, the shifting operation of the semi-automatic transmission is automated.

  FIG. 2 is a block diagram illustrating an example of a functional configuration realized in the hybrid ECU 18 that executes the program. That is, when the hybrid ECU 18 executes the program, the function of the torque control unit 30 (control means in the claims) is realized. Note that the friction map holding unit 31 is a storage area that holds a friction map 32 for reference by the torque control unit 30 and can be realized by allocating a part of the storage area of the memory 33 included in the hybrid ECU 18.

  Here, the friction map 32 is created on the basis of data acquired by performing an experiment such as a test run on the manufacturer side before the hybrid vehicle 1 is shipped. For example, in the engine running mode, the friction map 32 can be created by measuring the friction torque of the electric motor 13 corresponding to various rotational speeds of the engine 10 and associating them. In the example of the friction map 32 in FIG. 2, the friction torques (αN · m (Newton meter), βN · m, γN of the electric motor 13 corresponding to the rotation speed of the engine 10 (1000 rpm, 1500 rpm, 2000 rpm,...).・ M, ...) are recorded.

  The torque control unit 30 sends an engine torque control instruction and an electric motor torque control instruction to the engine ECU 11 and the electric motor ECU 17 based on the engine rotation speed information, the accelerator opening information, and the friction map 32 held in the friction map holding unit 31. It is a function to perform.

  Next, a torque control process performed in the hybrid ECU 18 that executes the program will be described with reference to the flowchart of FIG. Note that the flow from steps S1 to S4 in FIG. 3 is processing for one cycle, and the processing is repeatedly executed as long as the key switch 20 is in the ON state.

  In “START” in FIG. 3, the key switch 20 is in an ON state, the hybrid ECU 18 executes a program, and the function of the torque control unit 30 is realized in the hybrid ECU 18, and the procedure proceeds to step S1.

  In step S1, the torque control unit 30 determines whether or not the hybrid vehicle 1 is in the engine travel mode. If it is determined in step S1 that the hybrid vehicle 1 is in the engine travel mode, the procedure proceeds to step S2. On the other hand, if it is determined in step S1 that the hybrid vehicle 1 is not in the engine running mode, the procedure repeats step S1.

  In step S2, when the torque control unit 30 acquires the engine rotation speed information and the accelerator opening information, the procedure proceeds to step S3.

  In step S3, when the torque control unit 30 refers to the friction map 32 held in the friction map holding unit 31, the procedure proceeds to step S4.

  In step S4, the torque control unit 30 converts the accelerator opening information acquired in step S2 into a required torque. Further, the torque control unit 30 reads the friction torque of the electric motor 13 corresponding to the engine rotation speed indicated by the engine rotation speed information acquired in step S2 from the friction map 32 referred to in step S3. Further, the torque control unit 30 instructs the engine ECU 11 that the torque obtained by adding the read friction torque to the requested torque is the torque that the engine 10 should generate, and the motor 13 should generate this friction torque. The motor ECU 17 is instructed that the torque is present, and the process for one cycle is terminated (END).

In this way, the torque control unit 30 instructs the engine ECU 11 to generate a torque of (requested torque + α) and instructs the electric motor ECU 17 to generate a torque of (α). . As a result, the engine 10 and the electric motor 13 generate torque instructed by the torque control unit 30. At this time, if the friction torque of the electric motor 13 is subtracted from the torque of the engine 10,
(Requested torque + α) −α = Requested torque, and the required torque is input to the transmission 16. Further, since the torque α of the electric motor 13 is the friction torque itself of the electric motor 13, the electric motor 13 can generate the torque α without consuming electric power.

(About effect)
As described above, the control of the torque control unit 30 allows the electric motor 13 to eliminate the influence of the friction of the electric motor 13 during engine running without deteriorating the SOC without consuming electric power. Further, the control itself is a normal torque control, and no special control is required, and the control procedure can be simplified. For example, the zero torque control autonomously performed by the inverter 14 becomes unnecessary, and the hybrid ECU 18 can perform the control centrally, so that the control procedure can be simplified.

(Other embodiments)
In the above-described embodiment, the example in which the friction map 32 is used as information for the torque control unit 30 to read out the friction torque of the electric motor 13 according to the rotation speed of the engine 10 has been shown. A neural network in which the value of the friction torque of the electric motor 13 is calculated when the rotational speed of the engine 10 is input, or a membership function in which the value of the friction torque of the electric motor 13 is calculated by substituting the rotational speed of the engine 10 into a variable value. Various information may be used.

  Although the engine 10 has been described as an internal combustion engine, it may be a heat engine including an external combustion engine.

  Further, the program executed by the hybrid ECU 18 has been described as being installed in the hybrid ECU 18 in advance. However, a removable medium in which the program is recorded (a program is stored) is attached to a drive or the like (not shown), and the removable medium is removed. The program read from the medium is stored in a non-volatile memory inside the hybrid ECU 18 or the program transmitted via a wired or wireless transmission medium is received by a communication unit (not shown), and the hybrid ECU 18 Can be installed in the hybrid ECU 18 as a computer.

  Further, each ECU may be realized by an ECU in which these are combined into one, or an ECU that further subdivides the functions of each ECU may be provided.

  The program executed by the computer may be a program that is processed in time series in the order described in this specification, or in parallel or at a necessary timing such as when a call is made. It may be a program for processing.

  The embodiments of the present invention are not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Hybrid vehicle, 10 ... Engine, 11 ... Engine ECU, 12 ... Clutch, 13 ... Electric motor, 14 ... Inverter, 15 ... Battery, 16 ... Transmission, 17 ... Electric motor ECU, 18 ... Hybrid ECU (control device), 19 ... Wheels, 30 ... torque control unit (control means), 31 ... friction map holding unit, 32 ... friction map

Claims (5)

An engine and an electric motor, wherein the engine or the electric motor, or the engine and the electric motor can run in cooperation, and during the running by the engine, the rotating shaft of the electric motor outputs the output of the engine In the control device of the hybrid vehicle rotated by
While the engine is running, the engine is operated with a torque obtained by adding a friction torque of the motor corresponding to a preset rotational speed of the engine to a required torque, and the motor corresponds to the friction torque. Having control means for controlling to generate torque;
A control device characterized by that. The control device according to claim 1,
A friction map in which the friction torque of the electric motor according to the preset engine rotation speed is recorded;
The control means reads the friction torque of the electric motor from the rotational speed of the engine with reference to the friction map;
A control device characterized by that.   A hybrid vehicle comprising the control device according to claim 1. An engine and an electric motor, wherein the engine or the electric motor, or the engine and the electric motor can run in cooperation, and during the running by the engine, the rotating shaft of the electric motor outputs the output of the engine In the control method executed by the control device of the hybrid vehicle rotated by
While the engine is running, the engine is operated with a torque obtained by adding a friction torque of the motor corresponding to a preset rotational speed of the engine to a required torque, and the motor corresponds to the friction torque. Having a control step for controlling to generate torque;
A control method characterized by that.   A program for causing an information processing device to realize the function of the control device according to claim 1.

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