JP2022124616A - Temperature raising control device of battery - Google Patents

Abstract

To provide a temperature raising control device of a battery which is capable of raising a temperature of the battery for traveling even when the battery for traveling is at an extremely low temperature.SOLUTION: A temperature raising control device of a battery is installed on an electric vehicle which comprises: an internal combustion engine; an electric motor which generates driving power for driving wheels; a battery for traveling which accumulates electric power for traveling; a high voltage generator containing an adjustment circuit which generates electric power to be charged in the battery for traveling by receiving the driving power of the engine, as well as, adjusts a power generation amount; and load which actuates using output voltage of the battery for traveling as a power source. The temperature raising control device comprises: a temperature rising control part for causing the engine to drive in such a state that the adjustment circuit of the high voltage generator is in a non-operation state when temperature of the battery for traveling is a first temperature threshold value or less. Electric power (W1) is sent from the high voltage generator to the battery for traveling, the electric power (W1) being based upon induced voltage generated inside the high voltage generator by the engine caused to drive by the temperature rising control part.SELECTED DRAWING: Figure 4

Description

The present invention relates to a battery temperature increase control device.

2. Description of the Related Art In an electric vehicle equipped with a running battery that stores electric power for running, the electric power that can be discharged from the running battery is limited at low temperatures, and the electric motor may not be sufficiently driven. Patent Literature 1 proposes a control device that raises the temperature of a high-voltage battery (battery for driving) when the temperature of the high-voltage battery is lower than a predetermined temperature. The control device alternately drives the generator and the electric device, and periodically repeats charging and discharging of the high voltage battery, thereby increasing the temperature of the high voltage battery.

JP 2010-093883 A

By repeatedly charging and discharging the driving battery, Joule heat can be generated in the driving battery and the temperature of the driving battery can be increased. However, when the running battery is at an extremely low temperature, the chargeable power and dischargeable power of the running battery are very small. In this state, if an attempt is made to obtain charging power and discharging power of the driving battery by normal driving of the generator or normal driving of the electric device, the charging power and discharging power of the driving battery will exceed the chargeable power and dischargeable power of the driving battery. There is a risk that the

SUMMARY OF THE INVENTION It is an object of the present invention to provide a battery temperature increase control device capable of increasing the temperature of a driving battery even when the driving battery is at an extremely low temperature.

A battery temperature increase control device according to one aspect of the present invention includes:
An engine that is an internal combustion engine, an electric motor that generates power for the driving wheels, a driving battery that stores electric power for driving, and an amount of electric power generated by receiving power from the engine to generate charging power for the driving battery. and a high-voltage load that operates using the output voltage of the running battery as a power supply.
a temperature increase control unit that drives the engine while the adjustment circuit of the high-voltage generator is in a non-operating state when the temperature of the running battery is equal to or lower than a first temperature threshold;
Electric power based on an induced voltage generated inside the high-voltage generator is sent from the high-voltage generator to the running battery by driving the engine by the temperature increase control unit.

According to the present invention, by driving the engine while the adjustment circuit of the high-voltage generator is inactive, it is possible to output small charging power from the high-voltage generator based on the induced voltage of the high-voltage generator. can. Therefore, even if the chargeable power and dischargeable power of the running battery are extremely small, for example, at extremely low temperatures, the running battery can be charged within a range that does not exceed the chargeable power by using the small charging power. It becomes possible. By repeating such charging and discharging of the driving battery, it is possible to raise the temperature of the driving battery under extremely low temperatures.

1 is a block diagram showing an electric vehicle equipped with a temperature increase control device according to an embodiment of the present invention; FIG. 4 is a characteristic graph showing an example of the relationship between the temperature of the running battery and the chargeable power and dischargeable power; 5 is a flow chart showing a process of increasing the temperature of the driving battery, which is executed by the temperature increase control unit; 4 is a time chart showing a temperature raising operation when the temperature of the running battery is lower than the first temperature threshold; 4 is a time chart showing a temperature raising operation when the temperature of the running battery is between a first temperature threshold and a second temperature threshold;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an electric vehicle equipped with a temperature increase control device according to an embodiment of the present invention. The electric vehicle 1 of FIG. 1 is a HEV (Hybrid Electric Vehicle) having an engine 3, which is an internal combustion engine, and an electric motor 6 that generates power for running.

The electric vehicle 1 includes drive wheels 2 driven by an engine 3 or an electric motor 6, a transmission 5 for transmitting the power of the engine 3 to the drive wheels 2, an auxiliary machine 4 for operating the engine 3, and electric power for running. an inverter 7 that converts the electric power of the running battery 10 to drive the electric motor 6; and a second voltage that is lower than the first voltage of the running battery 10. A low-voltage load 11 that operates on a voltage (for example, 12V system), a low-voltage battery (for example, a lead battery) 12 that supplies a second voltage, and a DC/ A DC converter 13, a high voltage generator 14 that receives power from the engine 3 and generates charging power for the driving battery 10, a high voltage load 15 that operates using the first voltage of the driving battery 10 as a power supply voltage, and a driving operation unit 16 for inputting a driving operation by a person. Running battery 10 supplies a first voltage to inverter 7 and high voltage load 15 via power line L1. High voltage generator 14 may be referred to as a first voltage generator. High voltage load 15 may be referred to as a first voltage load.

The low-voltage load 11 includes a drive control unit 11A that controls the drive of the electric vehicle 1, a temperature increase control unit 11B that increases the temperature of the drive battery 10 when the temperature is extremely low, and a battery that manages the drive battery 10. A management unit 11C is included. An electrically driven device among the auxiliary devices 4 is included in the low-voltage load 11 . A combination of the temperature increase control section 11B and the switch 15a of the high voltage load 15 constitutes a temperature increase control device E for increasing the temperature of the driving battery 10 at an extremely low temperature.

The traveling control unit 11A is composed of one ECU (Electronic Control Unit) or a plurality of ECUs that operate in cooperation with each other. The travel control unit 11A receives a signal from the driving operation unit 16 and controls the auxiliary device or the inverter 7 according to the signal, thereby causing the engine 3 or the electric motor 6 to output power according to the driving operation.

Battery management unit 11C measures the temperature, voltage, charging/discharging current, etc., of driving battery 10, and calculates the temperature, voltage, charging/discharging current, remaining charge, chargeable power Win, dischargeable power Wout, etc. of driving battery 10. to manage.

FIG. 2 is a characteristic graph showing an example of the relationship between the temperature of the running battery and the chargeable power and dischargeable power. The traveling control unit 11A controls the power running operation and the regenerative operation of the electric motor 6 within the range of the chargeable electric power Win and the dischargeable electric power Wout. As shown in FIG. 2, the chargeable power Win and the dischargeable power Wout depend on the temperature of the running battery 10 and are very small values at extremely low temperatures. Traveling control unit 11A determines that travel by driving electric motor 6 is not possible because chargeable power Win and dischargeable power Wout are too small in temperature range WT1 in which travel battery 10 is at an extremely low temperature.

The high voltage load 15 is, for example, an air conditioner, and is connected to the power line L1 through which the first voltage (high voltage) is transmitted. In the case of an air conditioner, the high voltage load 15 includes an electric compressor and an inverter circuit that drives the electric compressor.

The high-voltage load 15 includes a switch 15a capable of inputting power from the power line L1 while in a non-operating state. The switch 15a is specifically a power semiconductor element or a relay that switches connection and disconnection between the power line L1 and the high-voltage load 15 . By switching the switch 15a to the connection state, while the high-voltage load 15 is inactive, power smaller than the operating power of the high-voltage load 15 is sent to the high-resistance electric circuit of the high-voltage load 15 to consume a small amount of power. can be done. For example, if the high-voltage load 15 is an air conditioner, the first voltage is input to the inverter circuit while each power semiconductor element of the inverter circuit is turned off. can consume power. Alternatively, if there is a load that flows a relatively large current to the power supply input section of the high-voltage load 15, the on/off control of the switch 15a with a low duty ratio allows a small amount of current to flow, resulting in a very small amount of current. can consume power.

The high-voltage generator 14 includes a power generation section 14a having a coil or a permanent magnet, an adjustment circuit 14b that rectifies the output of the power generation section 14a and adjusts the output voltage or the output power, and a control circuit 14c that controls the adjustment circuit 14b. have The adjustment circuit 14b includes a power semiconductor element, and the control circuit 14c controls switching of the power semiconductor element to adjust the output voltage or the output power. The adjustment circuit 14b is, for example, a regulator circuit, but may be an inverter circuit that receives a three-phase AC voltage and generates a DC voltage. The control circuit 14c may have a function of switching the output power according to the state of the engine 3 (for example, depending on whether the engine is started or in operation). Further, the control circuit 14c may have a digital interface and have a function of adjusting the output voltage or the output power in cooperation with the traveling control section 11A.

The gate driver, which drives the power semiconductor element in the adjustment circuit 14b, operates using the first voltage (high voltage) supplied from the running battery 10 as a power supply, and cannot operate without a stable supply of the first voltage. Become. When the control circuit 14c keeps the adjustment circuit 14b inactive and the engine 3 is driven at a low speed, the motion of the low speed rotation is input to the power generation unit 14a, and an induced voltage is generated in the coil of the power generation unit 14a. A small electric power based on the induced voltage can be output from the voltage generator 14 . The output power based on the induced voltage can be controlled to very small power by adjusting the rotational speed of the engine 3 . The rotation speed of the engine 3 is controlled by an auxiliary device 4 that operates using the low-voltage battery 12 as a power source. Therefore, even when the running battery 10 cannot stably supply electric power, the temperature rise control section 11B can stably control the rotation speed of the engine 3 and cause the high-voltage generator 14 to output very small electric power. can be done.

The temperature increase control unit 11B is composed of one ECU or a plurality of ECUs that operate in cooperation with each other. The temperature increase control unit 11B may be integrated with the travel control unit 11A, the battery management unit 11C, or both. Temperature information of the driving battery 10 is sent from the battery management unit 11C to the temperature increase control unit 11B. The temperature increase control unit 11B can output a drive command for idling operation of the engine 3 to the running control unit 11A, and can switch and control the switch 15a of the high voltage load 15. FIG.

Temperature increase control unit 11B executes a temperature increase process to hasten the temperature increase of driving battery 10 when driving battery 10 is at a low temperature. In the temperature raising process, as shown in the graph of FIG. 2, the contents of the process are switched based on the relationship between the temperature of the driving battery 10 and the first temperature threshold Tth1 and the second temperature threshold Tth2. The first temperature threshold value Tth1 is a value based on the upper limit value of the temperature range WT1 in which driving by the electric motor 6 is prohibited. A value based on the upper limit means a margin value for control, a correction value, an error amount, or a value obtained by adding a plurality of these to the upper limit. Values in the range of about 10°C may be meant. The second temperature threshold Tth2 is set to a temperature at which the chargeable electric power Win and the dischargeable electric power Wout of the driving battery 10 are still small although the temperature range WT1 is exceeded, and the temperature of the driving battery 10 is desired to be raised. be done.

<Temperature rising treatment>
FIG. 3 is a flowchart showing a process of increasing the temperature of the driving battery executed by the temperature increase controller. The temperature raising process is started when the system of the electric vehicle 1 is activated (activation button ON operation, ignition power ON operation, etc.). Alternatively, if the system of the electric vehicle 1 is configured to be able to reserve the travel start time, the time based on the reserved travel start time (for example, the time obtained by subtracting the estimated time required for the temperature raising process from the travel start time). , the temperature raising process may be started.

When the temperature increase process is started, temperature increase control unit 11B determines whether or not the temperature of driving battery 10 is equal to or lower than first temperature threshold value Tth1 (see FIG. 2) (step S1). As a result, if the temperature is not equal to or lower than the first temperature threshold value Tth1, the temperature increase control unit 11B terminates the temperature increase process. If the temperature exceeds the first temperature threshold value Tth1, it is possible to drive the electric motor 6 without increasing the temperature of the running battery 10. Therefore, when NO is determined in step S1 and the temperature increasing process ends, the running control unit 11A is operated. performs normal start-up processing and executes normal travel control. It should be noted that if temperature increase control section 11B determines NO in step S1, the process may proceed to step S5 in order to increase the temperature of driving battery 10 to a more desirable temperature.

On the other hand, if YES is determined in step S1, the temperature increase control unit 11B outputs a command to start the engine 3 to the running control unit 11A while the adjustment circuit 14b of the high voltage generator 14 remains in a non-operating state (step S2). ). In response to the start command, the rotary motion of the engine 3 is transmitted to the high voltage generator 14 while the adjustment circuit 14b is in a non-operating state. A small amount of power is output from the machine 14 .

Furthermore, the temperature rise control unit 11B performs switching control of the switch 15a so that the switch 15a of the high voltage load 15 is repeatedly switched from ON to OFF and then from OFF to ON (step S3). Then, the temperature increase control unit 11B determines whether the temperature of the driving battery 10 exceeds the first temperature threshold Tth1 (step S4), and repeats the switching control of step S3 until the determination result becomes YES.

By repeatedly switching on and off of the switch 15a by the loop processing of steps S3 and S4, the high-voltage load 15 consumes power slightly exceeding the small power generated from the high-voltage generator 14 and Interruption of consumption is repeated. Small charge power and small discharge power, which are the difference between the generated power and the consumed power, are alternately input to and output from battery 10 for running connected to power line L1. Since both the generated power and the consumed power are small, the temperature increase control unit 11B limits the charging power and the discharging power to a range not exceeding the chargeable power Win and the dischargeable power Wout at cryogenic temperatures. can be done. Then, in the loop processing of steps S3 and S4, the running battery 10 is repeatedly charged and discharged, so that Joule heat is generated in the running battery 10 and the temperature of the running battery 10 rises.

Note that the temperature rise control unit 11B prohibits the operation of the DC/DC converter 13 by the process of step S2a, thereby controlling the DC/DC converter 13 not to operate during the loop process of steps S3 and S4. may If the DC/DC converter 13 operates during the loop processing of steps S3 and S4, it becomes difficult to appropriately control the amplitude of charge/discharge power due to the power consumption of that amount. Therefore, by making the DC/DC converter 13 non-operating, the charging/discharging control during the loop processing can be realized with high reliability.

Further, during the loop processing of steps S<b>3 and S<b>4 , the travel control unit 11</b>A may perform travel control of the electric vehicle 1 using only the power of the engine 3 .

During the loop processing of steps S3 and S4, when the temperature of the running battery 10 rises and exceeds the first temperature threshold value Tth1, the temperature increase control unit 11B determines YES in step S4, and proceeds to the next step. . At this point, the temperature of the running battery 10 exits the temperature range WT1, and power supply from the running battery 10 becomes possible. Normal power generation operation of the generator 14 is enabled. Further, the high voltage load 15 can operate normally due to the power supply and the normal power generation of the high voltage generator 14 .

When the process proceeds to the next step, the temperature increase control unit 11B terminates switching control of the switch 15a of the high voltage load 15, and normally operates the high voltage load 15 based on the driver's operation (step S5). If there is no operation by the driver, the temperature increase control section 11B may start the normal operation of the high voltage load 15 in step S5. When the operation of the DC/DC converter 13 is prohibited in step S2a, the temperature rise control section 11B permits the operation of the DC/DC converter 13 in step S5a. With the permission, the DC/DC converter 13 operates after that, and it is possible to prevent the power of the low-voltage battery 12 from running out.

Next, the temperature rise control unit 11B outputs a command to the control circuit 14c of the high voltage generator 14, and repeatedly changes the power generated mainly by the power consumption of the high voltage load 15 (step S6). Then, the temperature increase control unit 11B determines whether the temperature of the running battery 10 exceeds the second temperature threshold value Tth2 (step S7), and repeats the control of the generated power in step S6 until the result of the determination becomes YES. .

Through the loop processing of steps S6 and S7, the generated power of the high-voltage generator 14 repeatedly changes in magnitude centering on the power consumption of the high-voltage load 15, so that the difference between the generated power and the power consumption becomes the driving battery 10. charging power and discharging power, and charging and discharging of the running battery 10 are repeated. As a result of the charging and discharging, Joule heat is generated in the running battery 10, and the temperature of the running battery 10 rises.

During the loop processing of steps S6 and S7, when the temperature of the running battery 10 rises and exceeds the second temperature threshold value Tth2, the temperature rise control unit 11B determines YES in step S7, and the high voltage generator 14 generates power. Power control ends (step S8). Then, the temperature raising process ends. After that, the high-voltage generator 14 operates normally, and the electric vehicle 1 operates normally.

<Temperature rising operation>
FIG. 4 is a time chart showing the temperature raising operation when the temperature of the running battery is lower than the first temperature threshold. FIG. 5 is a time chart showing the temperature raising operation when the temperature of the running battery is between the first temperature threshold and the second temperature threshold.

FIG. 4 shows the operation during the loop processing of steps S3 and S4 of the temperature raising process. During this period, power for idling operation of the engine 3 is input to the high-voltage generator 14 while the adjustment circuit 14b is in a non-operating state. A small output power W1 is generated by the internal induced voltage in the high-voltage generator 14 .

Further, during this period, switching control of the switch 15a of the high voltage load 15 is performed by the temperature rise control section 11B, and the high voltage load 15 consumes power W2 smaller than the normal operating power. Furthermore, the power consumption W2 is repeatedly changed in magnitude by the switching control described above.

The difference between the output power W1 of the high-voltage generator 14 and the power consumption W2 of the high-voltage load 15 is the charging/discharging power W3 of the driving battery 10 . Here, since the output power W1 and the power consumption W2 are small values, the charging/discharging power W3 can be repeatedly increased and decreased within a range not exceeding the chargeable power Win and the dischargeable power Wout at cryogenic temperatures. .

During the period of FIG. 4, as the temperature of driving battery 10 rises, the range of chargeable/dischargeable electric power Win, Wout of driving battery 10 increases. Therefore, the temperature rise control unit 11B changes the switching mode of the switch 15a of the high voltage load 15 as the temperature of the running battery 10 rises, thereby widening the charge/discharge power W3 of the running battery 10. You may control so that

FIG. 5 shows the operation during the loop processing of steps S6 and S7 of the temperature raising process. During this period, normal power consumption W2 is generated in the high voltage load 15 due to normal operation of the high voltage load 15 . In addition, in the high-voltage generator 14, normal power generation operation is performed by the control of the temperature rise control unit 11B, and the generated power is controlled, so that the output power (generated power) that changes relatively greatly W1 is generated.

The difference between the output power W1 of the high-voltage generator 14 and the power consumption W2 of the high-voltage load 15 is the charging/discharging power W3 of the running battery 10 . Since the output power W1 and the power consumption W2 are relatively large values, the chargeable power Win and the dischargeable power Win of the running battery 10, which are relatively large due to the temperature rising to the first temperature threshold Tth1 or higher, It becomes easy to generate charge/discharge power W3 with a relatively large amplitude corresponding to Wout.

During the period of FIG. 5, as the temperature of driving battery 10 rises, the range of chargeable/dischargeable power Win, Wout of driving battery 10 increases. Therefore, the temperature rise control unit 11B changes the amplitude of the power generation amount of the high-voltage generator 14 as the temperature of the running battery 10 rises, thereby controlling the charging/discharging power W3 to widen. may be performed.

As described above, according to the temperature increase control device E of the present embodiment, the temperature increase control unit 11B controls the adjustment circuit of the high voltage generator 14 when the temperature of the running battery 10 is equal to or lower than the first temperature threshold value Tth1. 14b is inactive and the engine 3 is driven. By driving the engine 3 , small electric power based on the induced voltage generated in the coil of the high voltage generator 14 can be output from the high voltage generator 14 . Therefore, by using the small electric power, it is possible to repeatedly charge and discharge the driving battery 10 with electric power within a range not exceeding the chargeable/dischargeable electric power Win, Wout at extremely low temperatures where the chargeable/dischargeable electric power Win, Wout is very small. , the temperature of the running battery 10 under extremely low temperatures can be increased.

Further, according to the temperature increase control device E of the present embodiment, the switch 15a is provided to allow power to be input to the high voltage load 15 while the high voltage load 15 is in non-operating state. When the temperature of the driving battery 10 is equal to or lower than the first temperature threshold value Tth1, the temperature increase control unit 11B performs control to repeatedly change the power consumption of the high voltage load 15 by controlling the switch 15a. Therefore, by controlling the switch 15a, it is possible to cause the high-voltage load 15 to generate power consumption smaller than the power consumption during operation. By combining the control of the power consumption and the small power output from the high-voltage generator 14, it is possible to generate a small charge/discharge power that does not exceed the chargeable/dischargeable power Win and Wout at cryogenic temperatures. The discharged power can raise the temperature of the running battery 10 at extremely low temperatures.

Furthermore, according to the temperature increase control device E of the present embodiment, when the temperature of the running battery 10 exceeds the first temperature threshold value Tth1, the temperature increase control unit 11B causes the high voltage load 15 to operate normally, and further , the high-voltage generator 14 is operated to generate power, and control is performed to repeatedly change the power generated. By switching the control, it is possible to generate charging/discharging electric power of the running battery 10 having a relatively large amplitude. Therefore, when the chargeable/dischargeable electric power Win, Wout of the running battery 10 becomes relatively large due to the temperature rise, the running battery 10 is made to perform relatively large charging/discharging corresponding to the case, thereby The battery 10 can be heated more quickly.

Furthermore, according to the temperature increase control device E of the present embodiment, the temperature increase control unit 11B prohibits the operation of the DC/DC converter 13 when the temperature of the driving battery 10 is equal to or lower than the first temperature threshold value Tth1. This prohibition control can prevent the power consumption of the DC/DC converter 13 from becoming an error factor in the charge/discharge power of the running battery 10. Therefore, the charge/discharge power is limited to a range that does not exceed the chargeable/dischargeable power Win and Wout. It can be generated reliably.

Furthermore, according to the temperature increase control device E of the present embodiment, the first temperature threshold Tth1 is set based on the upper limit value of the temperature range WT1 of the driving battery 10 in which the electric motor 6 cannot be driven. Therefore, even when the temperature is extremely low such that the electric motor 6 cannot be driven, the above-described temperature rise control of the running battery 10 can be performed with the small charging/discharging power.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments. For example, in the above embodiment, an air conditioner is shown as an example of a high-voltage load that consumes power to generate charging/discharging power, but the high-voltage load may be an inverter that drives an electric motor, for example. Also, any device may be applied as long as it operates using the output voltage of the running battery as a power source, such as an engine starting motor driven by the first voltage (high voltage). Further, in the above-described embodiment, an example is shown in which the high-voltage load 15 consumes power in order to generate the discharge power of the running battery under extremely low temperatures. However, it is possible to generate discharge power from a driving battery under extremely low temperatures in various ways, for example, by using a discharge-only electric load (such as a large resistor) to generate discharge power. Also, the illustrated chargeable/dischargeable power values, temperature threshold values, and the like are merely examples, and other details shown in the embodiments can be changed as appropriate without departing from the spirit of the invention.

REFERENCE SIGNS LIST 1 electric vehicle 2 drive wheel 3 engine 4 auxiliary machine 5 transmission 6 electric motor 7 inverter E temperature rise control device 10 battery for traveling 11 low voltage load 11A travel control section 11B temperature rise control section 11C battery management section 12 low voltage battery 13 DC /DC converter 14 high-voltage generator 14a power generation section 14b adjustment circuit 14c control circuit 15 high-voltage load 15a switch 16 operation section Win chargeable power Wout dischargeable power Tth1 first temperature threshold Tth2 second temperature threshold

Claims (5)

An engine that is an internal combustion engine, an electric motor that generates power for the driving wheels, a driving battery that stores electric power for driving, and an amount of electric power generated by receiving power from the engine to generate charging power for the driving battery. and a high-voltage load that operates using the output voltage of the running battery as a power supply.
a temperature increase control unit that drives the engine while the adjustment circuit of the high-voltage generator is in a non-operating state when the temperature of the running battery is equal to or lower than a first temperature threshold;
A temperature rise of a battery, wherein electric power based on an induced voltage generated inside the high voltage generator is sent from the high voltage generator to the driving battery by driving the engine by the temperature rise control unit. Control device. further comprising a switch capable of inputting power to the high voltage load while the high voltage load is inactive;
When the temperature of the running battery is equal to or lower than the first temperature threshold, the temperature increase control unit further controls the switch to repeatedly change the power input to the high voltage load. 2. The battery temperature increase control device according to claim 1. The temperature rise control unit is capable of outputting a load operation command and controlling the adjustment circuit,
The temperature increase control unit operates the high-voltage load when the temperature of the running battery is higher than the first temperature threshold and equal to or lower than a second temperature threshold higher than the first temperature threshold, and 3. A battery temperature rise control device according to claim 2, wherein the power generated by said high-voltage generator is repeatedly varied by controlling said adjustment circuit. mounted on an electric vehicle further comprising: a low-voltage load that operates at a voltage lower than the voltage of the running battery; and a DC/DC converter that converts the voltage of the running battery to the low voltage,
4. The battery temperature increase control device according to claim 3, wherein the temperature increase control unit stops the DC/DC converter when the temperature of the running battery is equal to or lower than the first temperature threshold. 5. The first temperature threshold value according to any one of claims 1 to 4, wherein the first temperature threshold is a value based on an upper limit value of a temperature range of the running battery that prohibits driving of the electric motor. battery temperature control device.

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