vehicle

Abstract

To provide a vehicle which can suppress deterioration of fuel consumption at the time of low load traveling and suppress occurrence of noise at the time of low background noise, while properly keeping a chip temperature at the time of high load traveling.SOLUTION: A vehicle V comprises: a battery BAT; a motor MOT1; a second inverter INV2 which converts DC power output from the battery BAT to AC power to be supplied to the motor MOT1; a converter VCU which boosts a DC voltage from the battery BAT to a boosted voltage that is a voltage input to the second inverter INV2 to be supplied to the second inverter INV2; a temperature control circuit 60 which circulates coolant through a second pump 621 to cool the second inverter INV2 and the converter VCU; and a controller ECU which controls the temperature control circuit 60. The controller ECU controls a flow rate of the second pump 621 based on the boosted voltage Vs boosted by the converter VCU and increases the flow rate of the second pump 621 when the boosted voltage Vs is a threshold voltage Th0 or more.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a vehicle. [Background technology]

[0002] In recent years, efforts to realize a low-carbon or carbon-free society have been intensifying as a concrete measure against global climate change. In automobiles and other vehicles, there is a demand for reducing CO2 emissions and improving energy efficiency, and the electrification of drive sources is progressing. For example, electric vehicles and hybrid electric vehicles have been developed that include a motor as a drive source for driving the drive wheels, a battery as a power source for supplying power to the motor, and a power conversion device that converts the battery's power and supplies it to the motor.

[0003] For example, the following Patent Document 1 discloses a vehicle temperature control system including a first temperature control circuit that controls the temperature of a motor, a second temperature control circuit that controls the temperature of a power conversion device, and a heat exchanger that exchanges heat between the first temperature control medium circulating in the first temperature control circuit and the second temperature control medium circulating in the second temperature control circuit. The first temperature control medium is typically ATF (Automatic transmission fluid), and the second temperature control medium is typically LLC (Long Life Coolant).

[0004] The power conversion device is equipped with chips such as IGBTs (Insulated Gate Bipolar Transistors), and is cooled by circulating the second temperature control medium cooled by the radiator using an electric pump. The flow rate of the electric pump can be controlled by increasing or decreasing the duty.

[0005] Examples of heat exchangers include converters that further boost the voltage from a high-voltage battery for hybrid vehicles, and inverters that convert DC and AC between the converter and the motor. Of these, converter chips have a very small thermal capacity, and are characterized by a rapid rise in temperature during vehicle operation that places a momentary high load, such as during WOT (Wide-Open-Throttle) when the accelerator is at its maximum opening or during strong regeneration. Because the temperature rises so quickly, if the duty of the electric pump is increased to request a high flow rate after the chip temperature has risen, the responsiveness of the increase in flow rate does not keep up with the rise in chip temperature, making it difficult to sufficiently cool the chip.

[0006] For this reason, it is necessary to increase the flow rate before high-load operation is performed, and when the temperature of the second temperature control medium is high, the duty of the electric pump is controlled to be kept high regardless of the operation of the vehicle. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2022-108684 A Summary of the Invention [Problem to be solved by the invention]

[0008] However, if duty control is performed based on the temperature of the second temperature control medium, the electric pump will be driven at a high duty if the temperature of the second temperature control medium is high, even in a fuel-saving control mode where high fuel efficiency is required, or during low background noise periods where noise reduction is required, and this poses issues with the power consumption of the electric pump and the operating noise of the electric pump.

[0009] The operating noise of an electric pump is small compared to the sound of the vehicle running or the engine sound, but this can become an issue if the pump continues to operate at a high duty ratio in situations where there is almost no background noise inside the vehicle cabin, such as during idling stop.

[0010] In addition, in hybrid vehicles, when the vehicle is stopped, heat from within the engine compartment is circulated to the radiator, which tends to cause the temperature of the second temperature control medium to become high. If duty control is performed based on the temperature of the second temperature control medium, it will often result in operation at a high duty even under conditions of low load and low background noise.

[0011] When the chip size is relatively large, the resistance to heat generation is high, so the required flow rate of the second temperature control medium is low, making it possible to optimize the chip temperature while avoiding deterioration in fuel efficiency and noise, but when the chip size is small, the required flow rate increases, making it difficult to optimize the chip temperature while avoiding deterioration in fuel efficiency and noise.In order to optimize the chip temperature while avoiding deterioration in fuel efficiency and noise, a control is required that can suppress increases in the flow rate during low-load driving and low background noise, while reliably supplying a high flow rate when the converter chip is under high load.

[0012] The present invention provides a vehicle that can properly maintain the chip temperature during high-load driving, while suppressing deterioration of fuel economy during low-load driving and noise generation during low background noise periods. [Means for solving the problem]

[0013] The present invention relates to A battery; A motor; an inverter that converts DC power output from the battery into AC power and supplies the AC power to the motor; a converter that boosts a DC voltage from the battery and supplies the boosted voltage to the inverter; a cooling device that circulates a refrigerant by an electric pump to cool the inverter and the converter; A vehicle including a control device that controls the cooling device, The control device includes: a flow rate of the electric pump is controlled based on the boosted voltage boosted by the converter; When the boosted voltage is equal to or greater than a first predetermined value, the flow rate of the electric pump is increased. Effect of the Invention

[0014] According to the present invention, it is possible to properly maintain the chip temperature during high-load running, while suppressing deterioration of fuel economy during low-load running and noise generation during low background noise periods. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a diagram showing an example of a schematic configuration of a vehicle V according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing an example of a schematic configuration of a main drive unit DU1 and a power conversion unit PCU. [Diagram 3] FIG. 2 is a diagram showing an example of a schematic configuration of a slave drive unit DU2. [Figure 4] 2 is a diagram showing an example of a schematic configuration of a temperature adjustment circuit 60. FIG. [Diagram 5] 13 is a timing chart of the current value I, boost voltage Vs, and chip temperature T_VCU when the brake pedal is depressed to cause strong regeneration by the motor MOT1 during normal driving at a constant vehicle speed in the engine driving mode. [Figure 6] 13 is a timing chart of the heat loss of the converter VCU, the flow rate of the second pump 621, and the chip temperature T_VCU when the brake pedal is depressed to perform strong regeneration by the motor MOT1 during normal driving at a constant vehicle speed in the engine driving mode. [Figure 7] 1 is a diagram showing the relationship between the rotation speed of a motor MOT1 and the torque and output. FIG. [Figure 8] FIG. 11 is a diagram showing motor torque during EV driving in 2WD and motor torque during EV driving in 4WD. [Figure 9] FIG. 13 is a diagram showing a modified temperature adjustment circuit 60. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of a vehicle according to the present invention will be described in detail with reference to the accompanying drawings. The drawings are to be viewed in the direction indicated by the reference symbols. In the following, the same or similar elements are denoted by the same or similar reference symbols, and their description may be omitted or simplified as appropriate.

[0017] [vehicle] Fig. 1 is a diagram showing an example of a schematic configuration of a vehicle V according to an embodiment of the present invention, in which thick solid lines indicate mechanical connections, dashed lines indicate electrical wiring, and solid arrows indicate control signals or detection signals.

[0018] As shown in FIG. 1, a vehicle V of this embodiment includes a main drive unit DU1 and a slave drive unit DU2.

[0019] The main drive unit DU1 includes a motor MOT1 and is configured to be capable of driving the front wheels FWR of the vehicle V by at least the power of the motor MOT1. The main drive unit DU1 is temperature-regulated (e.g., cooled) by a temperature regulation circuit 60 (e.g., a first temperature regulation circuit 61 described later) provided in the vehicle V.

[0020] The slave drive unit DU2 includes a motor MOT2 and is configured to be capable of driving the rear wheels RWR of the vehicle V by the power of the motor MOT2. For example, the slave drive unit DU2 is an air-cooled type that is cooled by outside air. This makes it possible to cool the slave drive unit DU2 with a simple configuration.

[0021] In this manner, the vehicle V equipped with the main drive unit DU1 and the slave drive unit DU2 is a so-called "four-wheel drive vehicle" configured to be capable of driving both the front wheels FWR and the rear wheels RWR.

[0022] The vehicle V further includes a battery BAT, a power conversion unit PCU, various sensors SNSR, and a control unit ECU.

[0023] The battery BAT is a chargeable and dischargeable secondary battery, has multiple storage cells connected in series or series-parallel, and is configured to be capable of outputting a high voltage of, for example, 100 to 400 V. As the storage cells of the battery BAT, lithium ion batteries (including so-called "all-solid-state batteries" using a solid electrolyte), nickel-metal hydride batteries, etc. can be used.

[0024] The power converter PCU is a device that converts the power exchanged between the main drive unit DU1 (e.g., motor MOT1) and the battery BAT, and between the secondary drive unit DU2 (e.g., motor MOT2) and the battery BAT. The power converter PCU may also convert the power exchanged between the main drive unit DU1 (e.g., generator GEN described below) and the secondary drive unit DU2 (e.g., motor MOT2). Details of the power converter PCU will be described later, so a description thereof will be omitted here.

[0025] The various sensors SNSR are sensors for acquiring information (hereinafter also referred to as "vehicle information") related to the vehicle V. For example, the various sensors SNSR include a vehicle speed sensor that detects the traveling speed (hereinafter also referred to as "vehicle speed") of the vehicle V, an accelerator pedal sensor that detects the amount of operation of the accelerator pedal (hereinafter also referred to as "AP opening"), a temperature sensor (for example, a power conversion device temperature sensor 62b described later) that detects the temperature of each part of the vehicle V (for example, the power conversion device PCU), and the like. The detection results by the various sensors SNSR are sent to the control device ECU as detection signals.

[0026] The control device ECU is a device (computer) that performs overall control of the entire vehicle V. The control device ECU controls the power conversion device PCU, the main drive unit DU1, the secondary drive unit DU2, and the temperature adjustment circuit 60, based on vehicle information acquired by, for example, various sensors SNSR. An example of specific control by the control device ECU will be described later, and therefore will not be described here.

[0027] The control device ECU is realized by, for example, an ECU (Electronic Control Unit) including a processor that performs various calculations, a storage device having a non-transitory storage medium that stores various information, an input / output device that controls input and output of data between the inside and outside of the control device ECU, etc. The control device ECU may be realized by one ECU, or may be realized by multiple ECUs working together.

[0028] [Power conversion device] Fig. 2 is a diagram showing an example of a schematic configuration of the main drive unit DU1 and the power converter PCU. As shown in Fig. 2, the power converter PCU includes a converter VCU, a first inverter INV1, a second inverter INV2, and a third inverter INV3.

[0029] The converter VCU is a DC-DC converter having switching elements (semiconductor elements) formed as chips, such as coils, capacitors, diodes, IGBTs (insulated gate bipolar transistors) and MOSFETs (metal oxide semiconductor field effect transistors), and has a function of converting an input voltage into a predetermined voltage and outputting it by switching the switching elements. For example, the output voltage of a battery BAT is input to the converter VCU, and the converter VCU outputs a boosted voltage Vs, which is a voltage obtained by boosting the output voltage of the battery BAT.

[0030] The converter VCU is provided with a current sensor 11, which detects a current output from the battery BAT to the converter VCU. A voltage sensor 12 is provided between the converter VCU and the first inverter INV1 and the second inverter INV2, which detects a boosted voltage Vs supplied from the converter VCU to the first inverter INV1 and the second inverter INV2.

[0031] The boosted voltage output from the converter VCU can be supplied to the motor MOT1 via the second inverter INV2. Furthermore, the boosted voltage can be supplied to the motor MOT2 via the third inverter INV3. That is, in the vehicle V, the boosted voltage generated by the single converter VCU can be commonly supplied to each of the motors MOT1 and MOT2. Therefore, the chip temperature of the VCU chip is likely to rise.

[0032] In addition, the converter VCU may step down the voltage input via the first inverter INV1, the second inverter INV2, or the third inverter INV3, and output the stepped down voltage to the battery BAT. That is, the converter VCU may output the input voltage to be input (i.e., charged) to the battery BAT.

[0033] The first inverter INV1, the second inverter INV2, and the third inverter INV3 each have a plurality of switching elements (not shown) formed as chips, such as IGBTs (insulated gate bipolar transistors) and MOSFETs (metal oxide semiconductor field effect transistors), and have the function of converting DC to AC and AC to DC by switching these switching elements.

[0034] For example, the first inverter INV1 may receive power (AC) generated by a generator GEN (described later) of the main drive unit DU1. In this case, the first inverter INV1 converts the AC received from the generator GEN into DC and outputs the DC to some or all of the converter VCU, the second inverter INV2, and the third inverter INV3.

[0035] The second inverter INV2 may receive the power (DC) of the battery BAT received via the converter VCU, or the power (DC) of the generator GEN received via the first inverter INV1. In this case, the second inverter INV2 converts the DC received from the battery BAT or the generator GEN to AC and outputs (i.e., supplies) it to the motor MOT1 of the main drive unit DU1. In addition, when regenerative power generation is performed by the motor MOT1, the second inverter INV2 may convert the power (AC) received from the motor MOT1 to DC and output it to the converter VCU, etc.

[0036] The third inverter INV3 may receive the power (DC) of the battery BAT received via the converter VCU, or the power (DC) of the generator GEN received via the first inverter INV1. In this case, the third inverter INV3 converts the DC received from the battery BAT or the generator GEN into AC and outputs (i.e., supplies) it to the motor MOT2 of the slave drive unit DU2 (see also FIG. 3). Furthermore, when regenerative power generation is performed by the motor MOT2, the third inverter INV3 may convert the power (AC) received from the motor MOT2 into DC and output it to the converter VCU, etc.

[0037] [Main drive unit] As shown in Fig. 2, the main drive unit DU1 includes an engine ENG, a generator GEN, a motor MOT1, and a first transmission mechanism T1. A gasoline engine, a diesel engine, or the like can be used as the engine ENG. For example, a three-phase AC motor can be used as the generator GEN and the motor MOT1. Details of the first transmission mechanism T1 will be omitted.

[0038] [Follower drive unit] Fig. 3 is a diagram showing an example of a schematic configuration of the slave driving unit DU2. As shown in Fig. 3, the slave driving unit DU2 includes a motor MOT2 and a second speed change mechanism T2. Details of the second speed change mechanism T2 will be omitted.

[0039] [Temperature control circuit] 4 is a diagram showing an example of a schematic configuration of the temperature adjustment circuit 60. As shown in FIG. 4, the temperature adjustment circuit 60 includes a first temperature adjustment circuit 61, a second temperature adjustment circuit 62, and a heat exchanger 63.

[0040] The first temperature control circuit 61 circulates the non-conductive first temperature control medium TCM1, and controls the temperature of the motor MOT1, the generator GEN, and the first speed change mechanism T1 (i.e., the main drive unit DU1). The first temperature control circuit 61 is provided with a first temperature sensor 61a that detects the temperature of the first temperature control medium TCM1 circulating through the first temperature control circuit 61. In this embodiment, the first temperature sensor 61a is provided in a storage section 612 that is an oil pan, and detects the temperature of the first temperature control medium TCM1 stored in the storage section 612. The first temperature sensor 61a outputs a detection value of the temperature of the first temperature control medium TCM1 stored in the storage section 612 to the control device ECU. This allows the control device ECU to obtain the temperature of the first temperature control medium TCM1.

[0041] The second temperature control circuit 62 circulates the conductive second temperature control medium TCM2, and controls the temperature of the power conversion device PCU. The second temperature control circuit 62 is provided with a second temperature sensor 62a that detects the temperature of the second temperature control medium TCM2 circulating through the second temperature control circuit 62. In this embodiment, the second temperature sensor 62a is provided in the pressure-feeding flow path 620a between the radiator 622 and the branching portion 624, and detects the temperature of the second temperature control medium TCM2. The second temperature sensor 62a outputs a detection value of the temperature of the second temperature control medium TCM2 discharged from the radiator 622 to the control device ECU. This allows the control device ECU to obtain the temperature of the second temperature control medium TCM2.

[0042] Further, the power converter PCU whose temperature is adjusted by the second temperature adjustment circuit 62 is provided with a power converter temperature sensor 62b for detecting the temperature of the power converter PCU. The power converter temperature sensor 62b outputs a detection signal indicating a detection value of the temperature of the power converter PCU to the control device ECU. Here, the power converter temperature sensor 62b may be configured to be capable of detecting the temperatures of the switching elements formed as chips that are built into the first inverter INV1, the second inverter INV2, the third inverter INV3, and the converter VCU. This allows the control device ECU to acquire the chip temperatures built into the power converter PCU.

[0043] The heat exchanger 63 exchanges heat between the first temperature control medium TCM1 circulating through the first temperature control circuit 61 and the second temperature control medium TCM2 circulating through the second temperature control circuit 62. As the first temperature control medium TCM1, for example, oil called ATF (Automatic Transmission Fluid) is used, which lubricates and controls the temperature of the motor MOT1, the generator GEN, and the first transmission mechanism T1. On the other hand, as the second temperature control medium TCM2, for example, cooling water called LLC (Long Life Coolant) is used.

[0044] The first temperature control circuit 61 is provided with first pumps 611a and 611b and a storage section 612. The first pump 611a is driven by the rotation of the engine ENG, and the first pump 611b is driven by the rotational force of the axle DS of the vehicle V. The first pumps 611a and 611b are mechanical pumps that pump the first temperature control medium TCM1. That is, the rotation speed of the first pump 611a varies according to the rotation speed of the engine ENG, and the rotation speed of the first pump 611b varies according to the vehicle speed. The storage section 612 stores the first temperature control medium TCM1 circulating through the first temperature control circuit 61. The storage section 612 is, for example, an oil pan provided at the bottom of a housing (not shown) that accommodates the motor MOT1, the generator GEN, and the first speed change mechanism T1.

[0045] The first temperature control circuit 61 also has a pumping passage 610a in which two first pumps 611a, 611b are arranged in parallel, a first branch passage 610b1 in which a motor MOT1 and a generator GEN are provided, a second branch passage 610b2 in which a first speed change mechanism T1 is provided, and a branch section 613 that branches the pumping passage 610a into the first branch passage 610b1 and the second branch passage 610b2.

[0046] The pressure-feeding passage 610a has an upstream end connected to the storage section 612, and passes through first pumps 611a and 611b, and has a downstream end connected to the branch section 613. The first branch passage 610b1 has an upstream end connected to the branch section 613, and passes through the motor MOT1 and the generator GEN, and has a downstream end connected to the storage section 612. The second branch passage 610b2 has an upstream end connected to the branch section 613, and passes through the first speed change mechanism T1, and has a downstream end connected to the storage section 612.

[0047] In the first temperature control circuit 61, the heat exchanger 63 is disposed upstream of the motor MOT1 and the generator GEN in the first branch flow path 610b1. Therefore, in the first temperature control circuit 61, (i) a first flow path is formed in parallel in which the first temperature control medium TCM1 pumped from the first pumps 611a and 611b passes through the first branch flow path 610b1 from the branch portion 613, is cooled by heat exchange with the second temperature control medium TCM2 in the heat exchanger 63, is supplied to the motor MOT1 and the generator GEN to lubricate and regulate the temperature of the motor MOT1 and the generator GEN, and is then stored in the storage portion 612, and (ii) a second flow path is formed in parallel in which the first temperature control medium TCM1 passes through the second branch flow path 610b2 from the branch portion 613, is supplied to the first speed change mechanism T1 to lubricate and regulate the temperature of the first speed change mechanism T1, and is then stored in the storage portion 612. The first temperature control medium TCM1 stored in the storage unit 612 flows through the pressure-feeding flow path 610a and is supplied to the first pumps 611a and 611b, and circulates between the first flow path and the second flow path.

[0048] The first temperature control circuit 61 further includes a pressure control circuit 610c provided with a pressure control valve 619. The pressure control circuit 610c has an upstream end connected to the reservoir 612 and a downstream end connected to the pumping flow path 610a downstream of the first pumps 611a and 611b. The pressure control valve 619 may be a check valve or an electromagnetic valve such as a solenoid valve. When the liquid pressure of the first temperature control medium TCM1 pumped from the first pumps 611a and 611b reaches a predetermined pressure or higher, the pressure control valve 619 opens, and a portion of the first temperature control medium TCM1 pumped from the first pumps 611a and 611b is returned to the reservoir 612. As a result, the liquid pressure of the first temperature control medium TCM1 flowing through the first branch flow path 610b1 and the second branch flow path 610b2 is maintained at a predetermined pressure or lower.

[0049] The second temperature control circuit 62 is provided with a second pump 621, a radiator 622, and a storage tank 623. The second pump 621 is an electric pump that is driven by, for example, the power of a battery BAT or the power generated by a generator GEN, and pumps the second temperature control medium TCM2, and is controlled by a control device ECU. The flow rate of the second pump 621 increases by increasing the duty and decreases by decreasing the duty.

[0050] Further, a rotation speed sensor 621a is attached to the second pump 621 to detect the rotation speed of the second pump 621. The rotation speed sensor 621a outputs a detection signal indicating the detection value of the rotation speed of the second pump 621 to the control device ECU. The control device ECU can estimate the flow rate of the second pump 621 based on the detection value of the rotation speed sensor 621a, i.e., the rotation speed of the second pump 621.

[0051] The radiator 622 is disposed at the front of the vehicle V, and is a heat dissipation device that cools the second temperature control medium TCM2 by wind generated when the vehicle V is traveling. The storage tank 623 is a tank that temporarily stores the second temperature control medium TCM2 circulating through the second temperature control circuit 62. Even if cavitation occurs in the second temperature control medium TCM2 circulating through the second temperature control circuit 62, the second temperature control medium TCM2 circulating through the second temperature control circuit 62 is temporarily stored in the storage tank 623, so that the cavitation occurring in the second temperature control medium TCM2 disappears.

[0052] The second temperature control circuit 62 has a branching section 624 and a junction section 625. In the second temperature control circuit 62, a storage tank 623, a second pump 621, and a radiator 622 are provided in this order from the upstream side. The second temperature control circuit 62 further has a pressure-feeding flow path 620a. The upstream end of the pressure-feeding flow path 620a is connected to the junction section 625, and passes through the storage tank 623, the second pump 621, and the radiator 622, and is connected to the branching section 624 at the downstream end. The second temperature control medium TCM2 stored in the storage tank 623 is pressure-fed by the second pump 621 through the pressure-feeding flow path 620a, and is cooled by the radiator 622.

[0053] The second temperature adjustment circuit 62 further includes a first branch flow path 620b1 in which the power converter PCU is provided, and a second branch flow path 620b2 in which a heat exchanger 63 is provided and which is provided in parallel to the first branch flow path 620b1.

[0054] Specifically, the first branch flow path 620b1 has an upstream end connected to the branch section 624, passes through the power converter PCU, and has a downstream end connected to the junction section 625. The second branch flow path 620b2 has an upstream end connected to the branch section 624, passes through the heat exchanger 63, and has a downstream end connected to the junction section 625.

[0055] In this embodiment, a valve device 626 serving as a flow control valve for adjusting the flow rate of the second temperature control medium TCM2 flowing through the second branch flow path 620b2 (in other words, the flow rate of the second temperature control medium TCM2 flowing through the first branch flow path 620b1) is provided upstream of the heat exchanger 63 in the second branch flow path 620b2.

[0056] In this embodiment, the valve device 626 is an ON-OFF valve. That is, the valve device 626 fully opens the second branch flow path 620b2 when opened, and fully closes the second branch flow path 620b2 when closed. The valve device 626 is not limited to an ON-OFF valve, and may be a variable flow rate valve that can adjust the flow rate of the second temperature control medium TCM2 flowing through the second branch flow path 620b2. The valve device 626 is controlled by the control device ECU.

[0057] The second temperature control medium TCM2, which is pumped by the second pump 621 in the pumping passage 620a and cooled by the radiator 622, branches into a first branch passage 620b1 and a second branch passage 620b2 at the branching section 624. The second temperature control medium TCM2 flowing through the first branch passage 620b1 cools the power converter PCU and merges with the second branch passage 620b2 and the pumping passage 620a at the merging section 625. The second temperature control medium TCM2 flowing through the second branch passage 620b2 cools the first temperature control medium TCM1 by exchanging heat with the first temperature control medium TCM1 in the heat exchanger 63, and merges with the first branch passage 620b1 and the pumping passage 620a at the merging section 625. The second temperature control medium TCM2 that has flowed through the first branch flow path 620b1 and the second temperature control medium TCM2 that has flowed through the second branch flow path 620b2 join at the junction 625, flow through the pumping flow path 620a, and are temporarily stored in the storage tank 623. The second temperature control medium TCM2 stored in the storage tank 623 is then supplied again to the second pump 621 through the pumping flow path 620a, and the second temperature control medium TCM2 circulates through the second temperature control circuit 62.

[0058] As an example, in the first temperature control circuit 61, if the temperature of the first temperature control medium TCM1 stored in the storage section 612 after cooling the motor MOT1, the generator GEN, and the first transmission mechanism T1 is approximately 100 [°C], then the first temperature control medium TCM1 of approximately 100 [°C] is supplied to the heat exchanger 63.

[0059] On the other hand, in the second temperature control circuit 62, if the temperature of the second temperature control medium TCM2 cooled by the radiator 622 is approximately 40°C, the second temperature control medium TCM2 supplied to the heat exchanger 63 does not pass through the power conversion unit PCU, which is the temperature-controlled device, and therefore the second temperature control medium TCM2 of approximately 40°C is supplied to the heat exchanger 63.

[0060] In this case, the heat exchanger 63 exchanges heat between the first temperature control medium TCM1 of about 100° C. and the second temperature control medium TCM2 of about 40° C., both of which are supplied to the heat exchanger 63. Then, for example, the first temperature control medium TCM1 of about 80° C. is discharged from the heat exchanger 63 to the downstream side of the first branch flow path 610b1 in the first temperature control circuit 61, and the second temperature control medium TCM2 of about 70° C. is discharged to the downstream side of the second branch flow path 620b2 in the second temperature control circuit 62.

[0061] In this way, the first temperature control medium TCM1 is cooled by the heat exchanger 63, so that the first temperature control medium TCM1 can be cooled without providing a separate radiator for cooling the first temperature control medium TCM1 in the temperature control circuit 60. Therefore, the temperature control circuit 60 can cool the first temperature control medium TCM1 flowing through the first temperature control circuit 61 and the second temperature control medium TCM2 flowing through the second temperature control circuit 62 with one radiator 622, so that the temperature control circuit 60 can be made compact.

[0062] In the first temperature adjustment circuit 61 of the temperature adjustment circuit 60 in Fig. 4, the power converter PCU is provided in the first branch flow path 620b1 between the branch portion 624 and the junction portion 625, and the heat exchanger 63 is provided in the second branch flow path 620b2 so as to be in parallel with the power converter PCU, but this is not limited to this. For example, as shown in Fig. 9, the storage tank 623, the second pump 621, the radiator 622, the power converter PCU, and the heat exchanger 63 may be provided in the pressure-feed flow path 620a, and the power converter PCU and the heat exchanger 63 may be provided in series.

[0063] [Control device] Next, a specific example of control by the control unit ECU will be described. First, the control of the main drive unit DU1 and the slave drive unit DU2 by the control unit ECU will be described.

[0064] When the vehicle V runs, the control unit ECU derives a required driving force (in other words, a driving force required for running the vehicle V) which is a target value for the driving force of the vehicle V, based on the vehicle speed detected by the vehicle speed sensor and the AP opening degree detected by the accelerator pedal sensor. Then, the control unit ECU controls the output from the main driving unit DU1 and the slave driving unit DU2 so that the driving force of the vehicle V becomes the required driving force.

[0065] For example, the control device ECU refers to an output distribution map (not shown) that defines the output distribution ratio of each of the main drive unit DU1 and the sub drive unit DU2, and distributes the required driving force between the output from the main drive unit DU1 and the output from the sub drive unit DU2. At this time, the control device ECU may set the output from one of the main drive unit DU1 and the sub drive unit DU2 (for example, the sub drive unit DU2) to 0.

[0066] [Drive mode] In this embodiment, the control device ECU is configured to be able to drive the main drive unit DU1 in a plurality of drive modes described below, and drives the vehicle V while appropriately switching the drive mode of the main drive unit DU1. This makes it possible to drive the vehicle V in an appropriate drive mode according to the state of the vehicle V.

[0067] <<1. EV driving mode>> The EV driving mode is a drive mode in which power from the battery BAT is supplied to the motor MOT1, and the vehicle V is driven by the power output by the motor MOT1 in response to this power.

[0068] In the EV driving mode, the output of power from the engine ENG is stopped, no power is input to the generator GEN, and no power is generated by the generator GEN.

[0069] <<2. Hybrid driving mode>> The hybrid driving mode is a drive mode in which at least electric power generated by the generator GEN is supplied to the motor MOT1, and the vehicle V is driven by power output by the motor MOT1 in response to this electric power.

[0070] In the hybrid driving mode, the control unit ECU injects fuel into the engine ENG, inputs power from the engine ENG to the generator GEN, and generates power using the generator GEN. The control unit ECU supplies the electric power generated by the generator GEN to the motor MOT1, and causes the motor MOT1 to output power corresponding to this electric power.

[0071] In the hybrid driving mode, the control unit ECU can also supply electric power from the battery BAT to the motor MOT1 as necessary. That is, in the hybrid driving mode, the control unit ECU can supply electric power from both the generator GEN and the battery BAT to the motor MOT1.

[0072] <<3. Engine driving mode>> The engine running mode is a drive mode in which the power output by the engine ENG is transmitted to the front wheels FWR through the power transmission path of the first transmission mechanism T1 to run the vehicle V.

[0073] In the engine drive mode, when the vehicle V is braked, regenerative power may be generated by the motor MOT1, and the battery BAT may be charged with the generated power.

[0074] In addition, in the engine running mode, the control unit ECU can supply electric power from the battery BAT to the motor MOT1 as necessary. As a result, in the engine running mode, the vehicle V can be run using the power output by the motor MOT1 using the electric power supplied from the battery BAT.

[0075] In the above explanation of the driving modes (EV driving mode, hybrid driving mode, engine driving mode), only the main drive unit DU1 has been explained, but in these EV driving mode, hybrid driving mode, and engine driving mode, electric power from the battery BAT or electric power generated by the generator GEN may be supplied to the motor MOT2 of the slave drive unit DU2, and the driving of the vehicle V may be assisted by the power output by the motor MOT2 in response to this electric power. Also, when braking the vehicle V, in addition to regenerative power generation by the motor MOT1, regenerative power may be generated by the motor MOT2 of the slave drive unit DU2, and the battery BAT may be charged with the generated electric power.

[0076] The vehicle V has a fuel-saving control mode that prioritizes fuel efficiency and a normal mode that consumes more power than the fuel-saving control mode. In the fuel-saving control mode, the output of the engine ENG and the motors MOT1 and MOT2 is limited compared to the normal mode, and the flow rate of the second pump 621 is also limited to a low flow rate.

[0077] [Control of temperature control circuit] Next, a description will be given of the control of the temperature regulation circuit 60 by the control unit ECU. In the following description, except for the description of 4WD driving, for simplicity's sake, the description will be given on the premise that the vehicle is driven by the main drive unit DU1.

[0078] When the power of the battery BAT is supplied to the motor MOT1, and when the power generated by regenerative power generation by the motor MOT1 is supplied to the battery BAT, the power passes through the converter VCU and the second inverter INV2 as described above. At this time, the switching element formed as a chip (hereinafter also referred to as the VCU chip) built into the converter VCU and the switching element formed as a chip (hereinafter also referred to as the INV chip) built into the second inverter INV2 generate heat.

[0079] During strong regeneration when the regenerative torque is large, and during WOT (Wide-Open-Throttle) when the accelerator opening is maximum in the EV driving mode and the hybrid driving mode, the heat generation (loss) of the VCU chip and the INV chip increases instantaneously. When the temperature of the VCU chip and the INV chip reaches a predetermined temperature (upper limit temperature Th1 described later), output is limited, so it is necessary to appropriately cool these chips by the above-mentioned temperature control circuit 60 (first temperature control circuit 61). In order to avoid the output limit, it is possible to actively cool the power conversion device PCU by constantly increasing the flow rate of the second pump 621, which is an electric pump, but it is necessary to prevent the driving sound of the second pump 621 from becoming a noise when the background noise of the vehicle V is small.

[0080] It is also necessary to avoid an increase in power consumption of the second pump 621 during running in the fuel saving control mode. Therefore, the control device ECU basically drives the second pump 621 in a low flow mode (for example, L1 (L / min) in FIG. 6), and increases the flow rate of the second pump 621 to drive it in a high flow mode (for example, L2 (L / min) in FIG. 6) only when a predetermined condition is satisfied.

[0081] Fig. 5 is a timing chart of a case where the brake pedal is depressed to cause strong regeneration by the motor MOT1 (hereinafter referred to as strong regeneration) from a state of normal driving at a constant vehicle speed in the engine driving mode (normal constant driving in the figure, hereinafter referred to as normal constant driving). Fig. 5 shows, from the top, the current value I of the current output from the battery BAT to the converter VCU, the boost voltage Vs supplied from the converter VCU to the second inverter INV2, and the chip temperature T_VCU of the VCU chip. In Fig. 5, the thick solid line indicates high vehicle speed driving, the dashed line indicates medium vehicle speed driving, and the dashed line indicates low vehicle speed driving. As can be seen from Fig. 5, the boost voltage Vs and the chip temperature T_VCU depend on the vehicle speed.

[0082] When the vehicle shifts from normal constant driving to strong regeneration, the current value I of the current output from the battery BAT to the converter VCU increases rapidly and reaches the maximum regeneration current value. The boost voltage Vs supplied from the converter VCU to the first inverter INV1 at this time does not change significantly from the normal constant driving and decreases as the vehicle decelerates. The chip temperature T_VCU of the VCU chip increases significantly during the transition.

[0083] The chip temperature T_VCU of the VCU chip during strong regeneration depends on the vehicle speed, and increases as the vehicle speed increases. If the symbol Th1 in the figure is the threshold temperature (hereinafter referred to as the upper limit temperature Th1) at which the output of the motors MOT1 and MOT2 is limited, the chip temperature T_VCU exceeds the upper limit temperature Th1 when the vehicle is traveling at high speed.

[0084] When the boost voltage Vs of the converter VCU is viewed at the same vehicle speed, the maximum value of the boost voltage Vs during strong regeneration is determined by the boost voltage Vs before strong regeneration. That is, since the maximum value of the boost voltage Vs during strong regeneration can be obtained based on the boost voltage Vs before strong regeneration, it is conceivable to control the increase in the flow rate of the second pump 621 based on the boost voltage Vs before strong regeneration.

[0085] To explain in more detail, the boost ratio of the converter VCU is controlled so that the total loss of the motor MOT1 and the second inverter INV2, the generator GEN and the first inverter INV1, and the converter VCU is minimized, and the boost ratio becomes higher mainly at higher rotation speeds of the motor MOT1. The heat generated in the VCU chip of the converter VCU increases as the boost ratio and current increase, but since the current is mainly proportional to the motor torque, it increases instantaneously during WOT and strong regeneration, whereas the boost ratio does not change as rapidly as the current and is determined approximately by the vehicle speed during WOT and before strong regeneration.

[0086] FIG. 6 is a timing chart in the case where strong regeneration is performed by the motor MOT1 from normal constant running in the engine running mode, as in FIG. 5. From the top, FIG. 6 shows the heat loss of the converter VCU, the flow rate of the second pump 621, and the chip temperature T_VCU of the VCU chip. In FIG. 6, the thick solid line shows the case where the flow rate of the second pump 621 is fixed at L1 (L / min) without a flow rate increase request, the dashed line shows the case where the flow rate of the second pump 621 is changed from L1 (L / min) to L2 (L / min) after the transition (hereinafter, a post-request), and the dashed line shows the case where the flow rate of the second pump 621 is changed from L1 (L / min) to L2 (L / min) before the transition (hereinafter, a pre-request). As can be seen from FIG. 6, the chip temperature T_VCU depends on the flow rate of the second pump 621 and the timing of changing the flow rate.

[0087] When the normal constant running state is shifted to the strong regeneration state, as described in FIG. 5, the current value I of the current output from the battery BAT to the converter VCU at the time of the shift increases rapidly. Accordingly, the heat loss of the converter VCU also increases rapidly. At this time, as shown by the thick solid line in FIG. 6, if the second pump 621 is not requested to increase the flow rate, the chip temperature T_VCU rises to a temperature H1. In contrast, as shown by the dashed and dotted line in FIG. 6, if the flow rate of the second pump 621 is increased based on the sudden increase in the current value I, that is, if the flow rate increase is requested after the shift, the flow rate of the second pump 621 increases a predetermined time (for example, 1 to 3 seconds) after a response delay occurs and the heat loss of the converter VCU increases rapidly. In this case, the chip temperature T_VCU rises to a temperature H2.

[0088] 6, when the flow rate of the second pump 621 is increased in advance based on the boost voltage Vs before strong regeneration, that is, when a flow rate increase is requested in advance before the transition, no response delay occurs and the flow rate of the second pump 621 increases before the heat loss of the converter VCU increases sharply. In this case, the chip temperature T_VCU rises to a temperature H3. Comparing the chip temperatures H1 to H3, it can be seen that the temperature H3 when the flow rate of the second pump 621 is increased based on the boost voltage Vs before strong regeneration is the lowest temperature, and the rise in the chip temperature T_VCU is effectively suppressed.

[0089] Therefore, the control device ECU controls the flow rate of the second pump 621 based on the boost voltage Vs boosted by the converter VCU. More specifically, as shown in Fig. 5, a threshold voltage Th0 of the boost voltage Vs is set so that the chip temperature T_VCU of the VCU chip cooled in a state where the flow rate of the second pump 621 is increased (L2 (L / min) in Fig. 6) does not exceed an upper limit temperature Th1. Note that this threshold voltage Th0 is a value that is not reached in the fuel saving control mode. Also, during idling stop, the converter VCU does not boost the voltage, so it goes without saying that this value is not reached.

[0090] The control device ECU does not increase the flow rate of the second pump 621 when the voltage is equal to or lower than the threshold voltage Th0 (L1 (L / min) in FIG. 6), and increases the flow rate of the second pump 621 when the voltage is equal to or higher than the threshold voltage Th0 (L2 (L / min) in FIG. 6). In this way, the control device ECU controls the flow rate of the second pump 621 based on the boosted voltage Vs boosted by the converter VCU, and increases the flow rate of the second pump 621 when the boosted voltage Vs is equal to or higher than the threshold voltage Th0, thereby suppressing an increase in the chip temperature of the VCU chip during high load operation. Furthermore, by controlling the flow rate of the second pump 621 based on the boosted voltage Vs boosted by the converter VCU, no response delay occurs compared to when the flow rate of the second pump 621 is controlled based on the current value I of the current output from the battery BAT to the converter VCU.

[0091] Moreover, when background noise is low, such as during idle stop, the converter VCU does not boost the voltage in the first place. Therefore, the boosted voltage Vs boosted by the converter VCU does not become equal to or higher than the threshold voltage Th0, and the flow rate of the second pump 621 is not increased. Therefore, noise due to the operation sound of the second pump 621 during low background noise can be suppressed.

[0092] Furthermore, during low-load running such as in the fuel-saving control mode, the boost ratio of the converter VCU is limited, so the boost voltage Vs boosted by the converter VCU does not become equal to or higher than the threshold voltage Th0, and the flow rate of the second pump 621 is not increased. Therefore, it is possible to avoid an increase in the power consumption of the second pump 621 during low-load running.

[0093] FIG. 7 is a diagram showing the relationship between the rotation speed of the motor MOT1 and the torque and output of the motor MOT1. The region indicated by S1 in Fig. 7 is a high vehicle speed region of the vehicle V. That is, this is a region in which the motor MOT1 is driven at high revolutions, low torque, and high output. In this region, the control device ECU controls the flow rate of the second pump 621 based on the boosted voltage Vs boosted by the converter VCU, as described above. As described above, in vehicle operations that instantaneously apply high loads, such as at full throttle (WOT) or strong regeneration, a rapid rise in the chip temperature of the VCU chip is predicted in advance, and the flow rate of the second pump 621 is increased in advance, thereby making it possible to suppress an increase in the chip temperature due to a response delay.

[0094] The region indicated by S2 in FIG. 7 is a low vehicle speed region of the vehicle V. That is, the motor MOT1 is driven at low revolutions, high torque, and low output. In this region, the control device ECU needs to suppress the rise in chip temperature of the converter VCU, etc., even if the boost voltage Vs boosted by the converter VCU is less than the threshold voltage Th0. In other words, in this region, even if the boost voltage Vs boosted by the converter VCU is less than the threshold voltage Th0, the chip temperature of the converter VCU, etc. may exceed the upper limit temperature Th1. In the EV driving mode (2WD) by the motor MOT1 described above, the load on the converter VCU and the second inverter INV2 is high, and the rise in the chip temperatures of these converters needs to be suppressed. On the other hand, in the EV driving (4WD) by the motors MOT1 and MOT2, the load on the converter VCU is high, and the rise in the chip temperature of the VCU chip needs to be suppressed.

[0095] 8 is a diagram showing motor torque during EV driving in 2WD and motor torque during EV driving in 4WD. The thick solid line is the torque of motor MOT1 during EV driving in 2WD (MOT1 torque (2WD)), the dashed line is the torque of motor MOT1 during EV driving in 4WD (MOT1 torque (4WD)), the dashed line is the torque of motor MOT2 during EV driving in 4WD (MOT2 torque (4WD)), and the dashed line is the total torque (total torque (4WD)) of motor MOT1 torque (MOT1 torque (4WD)) and motor MOT2 torque (MOT2 torque (4WD)) during EV driving in 4WD.

[0096] During EV driving in 2WD, if the torque of the motor MOT1 (MOT1 torque) is less than a predetermined threshold torque Th2, the control device ECU does not increase the flow rate of the second pump 621, and increases the flow rate of the second pump 621 when the torque is equal to or greater than the threshold torque Th2. Also, during EV driving in 4WD, if the total torque of the motors MOT1 and MOT2 (total torque (4WD)) is less than a predetermined threshold torque Th2, the control device ECU does not increase the flow rate of the second pump 621, and increases the flow rate of the second pump 621 when the total torque is equal to or greater than the threshold torque Th2. Note that this threshold torque Th2 is a value that is not reached in the fuel saving control mode. Needless to say, it is also a value that is not reached during idling stop.

[0097] In this way, in the low vehicle speed range, since the motor torque is closely related to the chip temperature, the response delay can be suppressed by controlling the flow rate of the second pump 621 based on the torque value or the torque command value. Also, during EV driving in 4WD, the occurrence of the response delay can be suppressed by comparing the total torque, which is the sum of the torque of the motor MOT1 (MOT1 torque (4WD)) and the torque of the motor MOT2 (MOT2 torque (4WD)), with the threshold torque Th2. This makes it possible to appropriately suppress the rise in the chip temperature even in the range that cannot be covered by the standard based on the boost voltage Vs.

[0098] Returning to FIG. 7, the region indicated by S3 is a medium vehicle speed region of the vehicle V. That is, this is a region in which the motor MOT1 is driven at medium rotation speed, high to medium torque, and medium to high output. In this region, as described above, the control device ECU needs to suppress an increase in the chip temperature of the VCU chip even if the boosted voltage Vs boosted by the converter VCU is less than the threshold voltage Th0. That is, even if the boosted voltage Vs boosted by the converter VCU is less than the threshold voltage Th0, there is a risk that the chip temperature of the VCU chip will exceed the upper limit temperature Th1.

[0099] The control device ECU does not increase the flow rate of the second pump 621 when the chip temperature of the VCU chip is below a threshold temperature Th3 (see FIG. 5) so that the chip temperature does not exceed the upper limit temperature Th1, and increases the flow rate of the second pump 621 when the chip temperature is equal to or higher than the threshold temperature Th3. In this region S3, the chip temperature does not rise so quickly that the upper limit temperature Th1 can be avoided even if the flow rate of the second pump 621 is directly controlled based on the chip temperature. Note that the threshold temperature Th3 is a value that is not reached in the fuel saving control mode. Needless to say, it is also a value that is not reached during idling stop. This makes it possible to appropriately suppress the rise in the chip temperature even in a region that cannot be covered by the standard based on the boost voltage Vs.

[0100] The control device ECU increases the flow rate of the second pump 621 when a requirement for increasing the flow rate is satisfied in either the overlapping region of region S1 and region S3 and the overlapping region of region S2 and region S3 shown in Fig. 7. This makes it possible to more appropriately cool the chip temperature in the region where the chip temperature may exceed the threshold voltage Th0.

[0101] Although the embodiment of the present invention has been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such an embodiment. It is clear that a person skilled in the art can come up with various modified or amended examples within the scope of the claims, and it is understood that these also naturally belong to the technical scope of the present invention. In addition, the components in the above embodiment may be arbitrarily combined within the scope of the invention.

[0102] For example, in the above-described embodiment, the main drive unit DU1 drives the front wheels FWR, and the slave drive unit DU2 drives the rear wheels RWR, but the main drive unit DU1 may drive the rear wheels RWR, and the slave drive unit DU2 may drive the front wheels FWR.

[0103] Furthermore, in the above-described embodiment, the main drive unit DU1 is the main drive source for the vehicle V, and the slave drive unit DU2 is the auxiliary drive source, but the main drive unit DU1 may be the auxiliary drive source, and the slave drive unit DU2 may be the main drive source for the vehicle V.

[0104] Furthermore, in the above-described embodiment, the vehicle V is a four-wheel drive vehicle in which the front wheels FWR can be driven by the main drive unit DU1 and the rear wheels RWR can be driven by the subordinate drive unit DU2, but this is not limited to this. For example, the vehicle V may be a two-wheel drive vehicle in which only the front wheels FWR can be driven by the main drive unit DU1 without providing the subordinate drive unit DU2 on the vehicle V.

[0105] In the above embodiment, the engine ENG is provided in the main drive unit DU1, and the vehicle V is a hybrid electric vehicle, but this is not limited to this. For example, the engine ENG may not be provided in the main drive unit DU1, and the vehicle V may be an electric vehicle.

[0106] Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and modifications, improvements, etc. are possible as appropriate.

[0107] This specification describes at least the following items. Note that, in parentheses, components corresponding to those in the above-mentioned embodiment are shown, but the present invention is not limited to these.

[0108] (1) A battery (battery BAT), A motor (motor MOT1) and an inverter (second inverter INV2) that converts DC power output from the battery into AC power and supplies the AC power to the motor; a converter (converter VCU) that supplies a boosted voltage obtained by boosting a DC voltage from the battery to the inverter; a cooling device (temperature control circuit 60) that circulates a refrigerant by an electric pump (second pump 621) to cool the inverter and the converter; A vehicle (vehicle V) including a control device (control device ECU) that controls the cooling device, The control device includes: a flow rate of the electric pump is controlled based on the boosted voltage boosted by the converter; When the boosted voltage is equal to or higher than a first predetermined value (threshold voltage Th0), the flow rate of the electric pump is increased.

[0109] In order to suppress the rise in the temperature (hereinafter, chip temperature) of the switching element of the converter by increasing the flow rate of the electric pump, it is not enough to do so after the high-load operation of the switching element has started. According to (1), the flow rate of the electric pump is increased based on the boost voltage after boosting of the converter as a pre-cause of the rise in chip temperature. That is, the flow rate of the electric pump is increased when it is predicted that the chip temperature will rise before the high-load operation of the switching element starts. This makes it possible to appropriately suppress the rise in the chip temperature of the converter during high-load operation without increasing the size of the converter chip. In addition, since the converter does not boost the voltage during low background noise such as during idle stop, the noise due to the operation sound of the electric pump can be suppressed. Furthermore, since the boost ratio of the converter is limited during low-load driving such as in the fuel-saving control mode, an increase in the power consumption of the electric pump can be avoided.

[0110] (2) A vehicle as described in (1), The motor includes a first motor that drives the front wheels and a second motor that drives the rear wheels, The control device further controls a flow rate of the electric pump based on a total torque of the first motor and the second motor. When the total torque is equal to or greater than a second predetermined value (threshold torque Th2), the flow rate of the electric pump is increased.

[0111] According to (2), the rise in chip temperature can be appropriately suppressed even in areas that cannot be covered by the standard of boost voltage. In addition, the total torque of the first motor for the front wheels and the second motor for the rear wheels can also be used to determine whether or not to increase the flow rate of the electric pump, thereby suppressing response delays.

[0112] (3) A vehicle as described in (2), The control device further controls the flow rate of the electric pump based on the temperature of a switching element of the converter. When the temperature of the switching element is equal to or higher than a third predetermined value (threshold temperature Th3), the flow rate of the electric pump is increased.

[0113] According to (3), when it is possible to increase the flow rate of the electric pump based on the temperature of the switching element in a timely manner, by increasing the flow rate of the electric pump based on the temperature of the switching element, it is possible to appropriately suppress the rise in chip temperature even in an area that cannot be covered by the standard based on the boost voltage.

[0114] (4) A vehicle as described in (1), A fuel-saving control mode that prioritizes fuel efficiency and a normal mode that consumes more power than the fuel-saving control mode, The first predetermined value is set to a value that is not reached in the fuel saving control mode.

[0115] According to (4), since the flow rate of the electric pump is not increased in the fuel-saving control mode, it is possible to avoid deterioration of fuel economy due to an increase in the flow rate of the electric pump in the fuel-saving control mode. [Explanation of symbols]

[0116] 60 Temperature control circuit (cooling device) 621 Second pump (electric pump) BAT Battery ECU Control Unit INV2 2nd inverter (inverter) VCU Converter MOT1 Motor (First Motor) Th0 threshold voltage (first predetermined value) Th2 Threshold torque (second predetermined value) Th3 Threshold temperature (third predetermined value) V Vehicle

Claims

1. A battery; A motor; an inverter that converts DC power output from the battery into AC power and supplies the AC power to the motor; a converter that boosts a DC voltage from the battery and supplies the boosted voltage to the inverter; a cooling device that circulates a refrigerant by an electric pump to cool the inverter and the converter; A vehicle including a control device that controls the cooling device, The control device includes: a flow rate of the electric pump is controlled based on the boosted voltage boosted by the converter; When the boosted voltage is equal to or greater than a first predetermined value, a flow rate of the electric pump is increased.

2. 2. A vehicle as claimed in claim 1, The motor includes a first motor that drives the front wheels and a second motor that drives the rear wheels, The control device further controls a flow rate of the electric pump based on a total torque of the first motor and the second motor. When the total torque is equal to or greater than a second predetermined value, a flow rate of the electric pump is increased.

3. 3. A vehicle according to claim 2, The control device further controls the flow rate of the electric pump based on the temperature of a switching element of the converter. When the temperature of the switching element is equal to or higher than a third predetermined value, the flow rate of the electric pump is increased.

4. 2. A vehicle as claimed in claim 1, A fuel-saving control mode that prioritizes fuel efficiency and a normal mode that consumes more power than the fuel-saving control mode, The first predetermined value is set to a value that is not reached in the fuel saving control mode.

Images