JP6614646B2 - Vehicle power supply system - Google Patents

Description

  The present invention relates to a vehicle power supply system.

  2. Description of the Related Art Conventionally, for example, a vehicle power supply system has been proposed that includes a travel battery that supplies power to a travel motor included in the vehicle, and a DC / DC converter that steps down the voltage from the travel battery and supplies the voltage to the auxiliary equipment side. (For example, refer to Patent Document 1).

JP 2014-233163 A

  FIG. 2 is a schematic configuration diagram of a conventional vehicle power supply system. As shown in FIG. 2, the traveling battery B1 is, for example, a battery of 100V to 350V class, and the electric power from the traveling battery B1 is supplied to the inverter INV via the bidirectional converter C1, and the motor generator The motor M in the MG is driven. The electric power from the traveling battery B1 is stepped down by the DC / DC converter C2 and supplied to the auxiliary machine side. An auxiliary battery B2 is provided on the auxiliary side. Further, the electric power from the traveling battery B1 is supplied to a high voltage load (for example, an electric air conditioner) D that is a load other than the motor M and does not pass through the DC / DC converter C2. A switch SW composed of a mechanical relay or a semiconductor relay (including switching means such as an FET) is provided between the battery B1 for traveling, the bidirectional converter C1, the DC / DC converter C2, and the high voltage load D. It has been.

  However, such a vehicle power supply system has the following problems. First, the rechargeable battery B1 is recharged to improve fuel efficiency. During regenerative charging, the voltage fluctuation is large and the noise of the motor M is very large. Therefore, in order to cope with these severe conditions, the DC / DC converter C2 and the circuit of the high-voltage load D tend to be complicated, resulting in an increase in cost.

  Furthermore, since the voltage of the battery B1 for traveling varies depending on the traveling performance of the vehicle, for example, in a range of 100V to 350V, the DC / DC converter C2 and the components on the high voltage load D side cannot be standardized.

  The present invention has been made to solve such problems, and the object of the present invention is to simplify the configuration of a DC / DC converter and a high-voltage load and to standardize parts. An object is to provide a vehicle power supply system that can perform the above-described operation.

A vehicle power supply system according to the present invention includes a travel battery that supplies electric power for driving a motor that is a power source for vehicle travel, a standard battery having an output voltage lower than that of the travel battery, and a voltage from the standard battery. The high-voltage load driven by the motor, the DC / DC converter that steps down the voltage from the standard battery and supplies it to the auxiliary machine side, the voltage from the battery for traveling, and the voltage during regeneration from the motor side are input. A step-down converter that charges the standard battery by stepping down an input voltage, an auxiliary path that connects the standard battery side and the motor side without going through the step-down converter, and provided on the auxiliary path And switch means for switching on and off .

  According to the vehicle power supply system of the present invention, there is provided a step-down converter capable of inputting a voltage from a traveling battery and a voltage during regeneration from the motor side and charging a standard battery by stepping down the input voltage. Therefore, the step-down converter is interposed between the motor and the DC / DC converter or the high-voltage load side, and the voltage step-down converter suppresses voltage fluctuation and noise when performing regenerative charging. Thereby, it is not necessary to make a high voltage load or a DC / DC converter circuit complicated in order to cope with severe conditions. Furthermore, even if the voltage of the running battery varies from vehicle to vehicle depending on the running performance of the vehicle, the voltage from the standard battery is supplied to the DC / DC converter and the high voltage load side, so the parts can be standardized. it can. Therefore, it is possible to simplify the configuration of the DC / DC converter and the high voltage load and to standardize the parts.

Further , since the auxiliary path connecting the standard battery side and the motor side and the switch means provided on the auxiliary path and switched on and off are provided , the voltage from the standard battery can be supplied to the motor, and the traveling When the power from the battery for the battery cannot be supplied, the vehicle can be tentatively driven by the voltage from the standard battery.

  In the vehicular power supply system according to the present invention, it is preferable that power supplied by regeneration is prohibited from being supplied to the auxiliary path when the switch unit is turned on.

  According to this vehicle power supply system, when the switch means is turned on, in order to prohibit power supplied by regeneration from being supplied to the auxiliary route, the voltage during regeneration with large fluctuations during temporary vehicle travel is provided. It is possible to prevent the motor noise from being added to the standard battery.

  ADVANTAGE OF THE INVENTION According to this invention, the power supply system for vehicles which can aim at simplification of the structure of a DC / DC converter and a high voltage load, and can also aim at standardization of components can be provided.

1 is a schematic configuration diagram of a vehicle power supply system according to an embodiment. It is a schematic block diagram of the conventional vehicle power supply system.

  Hereinafter, the present invention will be described according to preferred embodiments. Note that the present invention is not limited to the embodiments described below, and can be appropriately changed without departing from the spirit of the present invention. Further, in the embodiment described below, there is a part where illustration or description of a part of the configuration is omitted, but details of the omitted technology are within a range in which there is no contradiction with the contents described below. Needless to say, known or well-known techniques are applied as appropriate.

  FIG. 1 is a schematic configuration diagram of a vehicle power supply system according to the present embodiment. In the configuration shown in FIG. 1, the same or similar components as those shown in FIG. 2 are denoted by the same reference numerals.

  As shown in FIG. 1, the vehicle power supply system 1 according to this embodiment includes a traveling high-voltage power supply group 10 and a standard high-voltage power supply group 20. In the present embodiment, the configuration of the traveling high-voltage power supply group 10 is determined according to the traveling performance, and the configuration of the standard high-voltage power supply group 20 can be standardized.

  The traveling high-voltage power supply group 10 uses devices according to traveling performance, and includes a traveling battery B1, a bidirectional converter C1, an inverter INV, a motor generator MG including a motor M, and a first path L1. The first switch SW1 is provided.

  In the present embodiment, the traveling battery B1 outputs a voltage of, for example, 300 V or more, and supplies electric power that drives a motor M that is a power source for traveling the vehicle. The motor M in the motor generator MG is a driving motor for driving the vehicle, and is driven by the electric power from the driving battery B1 through the bidirectional converter C1 and the inverter INV. The first switch SW1 is provided on the first path L1 between the traveling battery B1 and the bidirectional converter C1, and supplies power from the traveling battery B1 to the motor M side by turning on and off. Or shut off. Furthermore, the battery B1 for driving | running | working accepts the electric power at the time of regeneration at the time of ON of 1st switch SW1, and charges it.

  The standard high voltage power supply group 20 includes a standard battery B3, a high voltage load D, a DC / DC converter C2, and a standard high voltage J / B 21.

  The standard battery B3 is a battery having an output voltage lower than that of the traveling battery B1, and outputs a voltage of, for example, 96V in the present embodiment. The high-voltage load D is driven by the voltage from the standard battery B3, and corresponds to, for example, an electric air conditioner. The DC / DC converter C2 steps down the voltage from the standard battery B3 and supplies it to the auxiliary machine side. An auxiliary battery B2 is provided downstream of the DC / DC converter C2.

  The standard high voltage J / B 21 includes a second path L2 connected from the standard battery B3 to the high voltage load D and the DC / DC converter C2, and also includes a second switch SW2 on the second path L2. The second switch SW2 is configured by a mechanical or semiconductor relay (including switching means such as an FET). When the second switch SW2 is turned on, power from the standard battery B3 is supplied to the high voltage load D and the DC / DC converter C2. Supplied.

  Further, in the present embodiment, the vehicle power supply system 1 includes a step-down converter C3, a third path (auxiliary path) L3, and a third switch (switch means) SW3. These configurations are interposed between the traveling high-voltage power supply group 10 and the standard high-voltage power supply group 20.

  The step-down converter C3 can input a voltage from the traveling battery B1 and a voltage during regeneration from the motor M, and charges the standard battery B3 by stepping down the input voltage. Specifically, the step-down converter C3 has an input side between the first switch SW1 and the bidirectional converter C1, and an output side that is a standard battery B3.

  The third path L3 is a path that connects the standard battery B3 side and the motor M side. Specifically, the third path L3 has one end connected to the second path L2 in the standard high voltage J / B 21 and the other end connected to the bidirectional converter C1. The other end may be connected to the motor M side by being connected to a place other than the bidirectional converter C1. Further, the one end side is not limited to the second path L2, and may be connected to another location and connected to the standard battery B3 side.

  The third switch SW3 is a mechanical or semiconductor relay (including switching means such as an FET) that is provided on the third path L3 and switched on and off. The third switch SW3 is a component that is electrically interposed between the traveling high-voltage power supply group 10 and the standard high-voltage power supply group 20, but is incorporated in the standard high-voltage J / B 21 as in the present embodiment. It may be configured as one part of the standard high-voltage power supply group 20.

  Next, operation | movement of the vehicle power supply system 1 which concerns on this embodiment is demonstrated. First, it is assumed that the first switch SW1 is on. At this time, the motor M is driven by the electric power from the traveling battery B1, and the vehicle travels. Furthermore, regenerative power is generated during regenerative travel of the vehicle. The traveling battery B1 is charged with regenerative power.

  If the second switch SW2 is turned on, the power from the standard battery B3 is supplied to the high voltage load D and the DC / DC converter C2. As a result, the high-voltage load D is driven, and the voltage from the standard battery B3 is stepped down by the DC / DC converter C2 and supplied to the auxiliary machine side.

  Further, the step-down converter C3 can receive the voltage from the traveling battery B1 and the voltage during regeneration, and steps down the input voltage to charge the standard battery B3. In addition, the step-down converter C3 is interposed between the traveling high-voltage power supply group 10 and the standard high-voltage power supply group 20 in order to prevent voltage fluctuation and noise during regeneration from being directly applied to the standard battery B3. ing. This suppresses the influence of voltage fluctuation and noise on the high-voltage load D and the DC / DC converter C2 side. Therefore, the complexity of the circuits of the high-voltage load D and the DC / DC converter C2 is suppressed.

  Even if the voltage of the running battery B1 varies depending on the vehicle depending on the running performance of the vehicle, the voltage from the standard battery B3 is supplied to the DC / DC converter C2 and the high voltage load D side. Standardization can be achieved.

  In addition, there is a possibility that the motor M cannot be driven by the electric power from the traveling battery B1 when the traveling battery B1 is damaged or deteriorated. In this case, the third switch SW3 is turned on. Thus, the standard battery B3 side and the motor M side are electrically connected, and the motor M can be driven by the standard battery B3. As a result, even when the motor M cannot be driven by the power from the traveling battery B1, the vehicle can travel with the power from the standard battery B3.

  When the third switch SW3 is turned on, it is preferable to prohibit power supplied by regeneration from being supplied to the third path L3. In this case, for example, by providing other switch means and turning off the other switch means during regenerative travel, the power generated by regeneration is not supplied to the third path L3, or the regeneration is prohibited by other known regenerative charge prohibiting means. It is sufficient to prevent the electric power from being supplied to the third path L3.

  Thus, according to the vehicle power supply system 1 according to the present embodiment, the voltage from the traveling battery B1 and the voltage at the time of regeneration from the motor M side can be input, and the input voltage is stepped down. Since the step-down converter C3 for charging the standard battery B3 is provided, the step-down converter C3 suppresses voltage fluctuation and noise when performing regenerative charging. Thereby, it is not necessary to make the circuit of the high voltage load D and the DC / DC converter C2 complicated in order to cope with severe conditions. Furthermore, even if the voltage of the running battery B1 varies depending on the running performance of the vehicle, the voltage from the standard battery B3 is supplied to the DC / DC converter C2 and the high voltage load D side. Can be standardized. Therefore, it is possible to simplify the configuration of the DC / DC converter C2 and the high-voltage load D and to standardize parts.

  Further, since it further includes a third path L3 that connects the standard battery B3 side and the motor M side, and a third switch SW3 that is provided on the third path L3 and is switched on and off, the standard battery B3 is connected to the motor M. Can be supplied, and when the power from the running battery B1 cannot be supplied, the vehicle can be tentatively driven by the voltage from the standard battery B3.

  Further, when the third switch SW3 is turned on, it is prohibited to supply electric power due to regeneration to the third path L3. Therefore, when the vehicle is temporarily running, the voltage or motor noise during regeneration with a large fluctuation is generated. Can be prevented from being added to the standard battery B3.

  As described above, the present invention has been described based on the embodiments, but the present invention is not limited to the above-described embodiments, and may be modified without departing from the spirit of the present invention, and may be appropriately changed within a possible range. These techniques may be combined.

  For example, the voltage values of the batteries B <b> 1 to B <b> 3 shown in the above embodiment are not limited to the above and can be changed as appropriate.

1: Vehicle power supply system 10: Traveling high-voltage power supply group 20: Standard high-voltage power supply group B1: Traveling battery B2: Auxiliary battery B3: Standard battery C1: Bidirectional converter C2: DC / DC converter C3: Step-down converter D: High voltage load INV: Inverter L1: First path L2: Second path L3: Third path (auxiliary path)
M: Motor MG: Motor generator SW1: First switch SW2: Second switch SW3: Third switch (switch means)

Claims (3)

A battery for running that supplies electric power for driving a motor that is a power source for running the vehicle;
A standard battery having an output voltage lower than that of the battery for traveling;
A high voltage load driven by a voltage from the standard battery;
A DC / DC converter that steps down the voltage from the standard battery and supplies it to the auxiliary machine side;
A step-down converter that can input a voltage from the battery for traveling and a voltage at the time of regeneration from the motor side and charges the standard battery by stepping down the input voltage;
An auxiliary path for connecting the standard battery side and the motor side without going through the step-down converter;
Switch means provided on the auxiliary path and switched on and off;
A vehicle power supply system comprising: 2. The vehicle power supply system according to claim 1 , wherein when the switch unit is turned on, power supplied by regeneration is prohibited from being supplied to the auxiliary path. A bi-directional converter capable of bi-directional voltage adjustment interposed between the motor and the running battery;
The vehicular power supply system according to claim 1 , wherein the auxiliary path connects the standard battery side and the bidirectional converter .

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