Vehicle thermal management system

Abstract

To increase the rate at which the battery heats up in low-temperature environments. [Solution] The system includes a heating circuit 10, a cooling circuit 20, a battery oil circuit 30 that circulates insulating oil to cool the battery 77, a motor oil circuit 40 that circulates cooling oil for the motor generator 70, a first switching circuit 19 that switches between thermal connection and disconnection between the heating circuit 10 and the battery oil circuit 30, and a second switching circuit 49 that switches between thermal connection and disconnection between the motor oil circuit 40 and the battery oil circuit 30. When the vehicle 200 is running on the motor generator 70, the first switching circuit 19 thermally disconnects the heating circuit 10 and the battery oil circuit 30, and the second switching circuit 49 thermally connects the motor oil circuit 40 and the battery oil circuit 30. When the vehicle 200 is stopped, the first switching circuit 19 thermally connects the heating circuit 10 and the battery oil circuit 30, and the second switching circuit 49 thermally disconnects the motor oil circuit 40 and the battery oil circuit 30.

Description

Technical Field

[0001] The present disclosure relates to the configuration of a vehicle thermal management system that cools and warms up a battery mounted on a vehicle.

Background Art

[0002] Patent Document 1 discloses a battery module that cools a plurality of battery cells housed therein with insulating oil.

[0003] Patent Document 2 discloses a method of warming up a battery by increasing the loss of a motor generator to increase the self-heating amount in a drive device including an engine, a motor generator, and an oil circulation system that circulates oil to a battery.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in a battery system provided with a cooling system using insulating oil as a refrigerant, it is required to increase the temperature rising rate of the battery in a low-temperature environment. Therefore, the vehicle thermal management system of the present disclosure aims to increase the temperature rising rate of the battery in a low-temperature environment.

Means for Solving the Problems

[0006] The vehicle thermal management system disclosed herein includes a heating circuit that circulates hot water heated by an electric heater to heat the passenger compartment, a cooling circuit that circulates a refrigerant to cool the passenger compartment, a battery oil circuit that is thermally connected to the cooling circuit and circulates insulating oil to cool the battery, a motor oil circuit that circulates cooling oil for a motor generator for vehicle drive, a first switching circuit that switches the thermal connection and disconnection between the heating circuit and the battery oil circuit, a second switching circuit that switches the thermal connection and disconnection between the motor oil circuit and the battery oil circuit, and the first switching circuit and the The system comprises a control device that adjusts the operation of a second switching circuit, wherein, when the vehicle is running on the motor generator, the control device thermally disconnects the heating circuit and the battery oil circuit with the first switching circuit and thermally connects the motor oil circuit and the battery oil circuit with the second switching circuit, and when the vehicle is stopped, the first switching circuit thermally connects the heating circuit and the battery oil circuit and thermally disconnects the motor oil circuit and the battery oil circuit with the second switching circuit.

[0007] This allows the battery to be heated even when the vehicle is stopped, by thermally connecting the heating circuit and the battery oil circuit, and using the heat from the electric heater to raise the battery temperature. This enables the battery to be heated even when the vehicle is stationary. This allows for a higher rate of battery heating in low-temperature environments. Furthermore, when the vehicle is running on the motor generator, the motor oil circuit and the battery oil circuit are thermally connected, and the battery is heated by the heat from the motor generator, allowing for efficient battery heating.

[0008] In the vehicle thermal management system of the present disclosure, the control device may, when the vehicle is running on the motor generator and the temperature of the coolant is below a predetermined threshold, thermally connect the heating circuit and the battery oil circuit with the first switching circuit and thermally disconnect the motor oil circuit and the battery oil circuit with the second switching circuit, and thereafter, when the temperature of the coolant rises above the predetermined threshold, thermally connect the motor oil circuit and the battery oil circuit with the second switching circuit, and thereafter, when the temperature of the battery rises above the heater heating stop temperature, thermally disconnect the heating circuit and the battery oil circuit with the first switching circuit.

[0009] This allows the heating circuit and battery oil circuit to be thermally connected when the motor generator's cooling oil temperature is low, raising the battery temperature with the heat from the electric heater. When the cooling oil temperature exceeds a predetermined threshold, the motor oil circuit and battery oil circuit are thermally connected again, raising the battery temperature with the heat from the electric heater and the motor generator. When the battery temperature exceeds the heater heating stop temperature, the heating circuit and battery oil circuit are thermally disconnected, allowing the battery temperature to be raised by the heat from the motor generator. This increases the rate at which the battery heats up in low-temperature environments and allows for efficient battery heating.

[0010] The vehicle thermal management system of the present disclosure includes a motor cooling water circuit that circulates cooling water through a radiator to cool the motor generator, and a cooling water flow control valve that adjusts the flow rate of the cooling water flowing through the radiator, wherein the control device may, when the vehicle is running on the motor generator and the temperature of the cooling oil is below a predetermined threshold, block the flow of the cooling water to the radiator with the cooling water flow control valve, and then, when the temperature of the cooling oil rises above the predetermined threshold, allow the cooling water to flow through the radiator with the cooling water flow control valve.

[0011] This reduces the amount of heat released from the motor generator to the outside air, allowing the motor generator's cooling oil to heat up faster, and thus the battery to heat up faster.

[0012] In the vehicle thermal management system of the present disclosure, a cooling oil pump is included for circulating the cooling oil in the motor oil circuit, and the control device may adjust the operation of the motor generator and the cooling oil pump, and when the vehicle is running on the motor generator and the temperature of the cooling oil is below a predetermined threshold, the loss of the motor generator may be increased to increase the amount of self-heating, and the flow rate of the cooling oil pump may be increased.

[0013] This increases the temperature of the motor generator and thus the rate at which the motor generator's cooling oil heats up, which in turn increases the rate at which the battery heats up. In addition, the cooling oil pump increases the flow rate of the cooling oil circulating in the motor oil circuit, allowing the heat generated in the motor generator 70 to be effectively transferred to the insulating oil. This increases the rate at which the insulating oil and the battery heat up.

[0014] In the vehicle thermal management system of the present disclosure, the first switching circuit comprises a water-oil heat exchanger that performs heat exchange between the hot water and the insulating oil and heats the insulating oil with the hot water, and a hot water flow rate control valve that adjusts the flow rate of the hot water flowing through the water-oil heat exchanger; the second switching circuit comprises an oil-oil heat exchanger that performs heat exchange between the cooling oil and the insulating oil and heats the insulating oil with the cooling oil, and a cooling oil flow rate control valve that adjusts the flow rate of the cooling oil flowing through the oil-oil heat exchanger; and the control device controls the water-oil heat exchanger by means of the hot water flow rate control valve. The heating circuit and the battery oil circuit may be thermally connected by passing the hot water through the exchanger, the heating circuit and the battery oil circuit may be thermally isolated by blocking the flow of the hot water to the water-oil heat exchanger with the hot water flow rate control valve, the motor oil circuit and the battery oil circuit may be thermally connected by passing the cooling oil through the oil-oil heat exchanger with the cooling oil flow rate control valve, and the motor oil circuit and the battery oil circuit may be thermally isolated by blocking the flow of the cooling oil to the oil-oil heat exchanger with the cooling oil flow rate control valve.

[0015] This allows for a simple configuration that increases the rate at which the battery heats up in low-temperature environments. [Effects of the Invention]

[0016] The vehicle thermal management system disclosed herein can increase the rate at which the battery heats up in low-temperature environments. [Brief explanation of the drawing]

[0017] [Figure 1] This is a system diagram showing the configuration of the vehicle thermal management system according to the embodiment. [Figure 2] This is a flowchart showing the operation of the vehicle thermal management system according to the embodiment. [Figure 3] This is a continuation of the flowchart shown in Figure 2. [Modes for carrying out the invention]

[0018] The vehicle thermal management system 100 of an embodiment will be described below with reference to the drawings. As shown in Figure 1, the vehicle thermal management system 100 includes a heating circuit 10, a cooling circuit 20, a battery oil circuit 30, a motor oil circuit 40, a motor cooling water circuit 50, and a control device 60. The vehicle thermal management system 100 is mounted on a vehicle 200. The vehicle 200 is an electric vehicle that runs on a motor generator 70 for propulsion. In Figure 1, solid lines indicate the heating circuit 10, dashed lines indicate the cooling circuit 20, double solid lines indicate the battery oil circuit 30, double dashed lines indicate the motor oil circuit 40, and dashed lines indicate the motor cooling water circuit 50. Thin dashed lines indicate the flow of commands, signals, or data.

[0019] The heating circuit 10 is a circuit that circulates hot water to heat the vehicle interior. The heating circuit 10 includes a hot water pump 11, a high-pressure electric heater 12, a hot water flow control valve 14, a heater core 13, and a hot water flow path 16 of a water-oil heat exchanger 75.

[0020] The warm water pump 11 is a pump that circulates warm water in the heating circuit 10. The high-voltage electric heater 12 is, for example, a heater that is driven at a high voltage of 200 to 400V and heats the water flowing through it to warm water. The heater core 13 is a heat exchanger between the warm water heated by the high-voltage electric heater 12 and the air in the vehicle interior. The water-oil heat exchanger 75 is arranged across the heating circuit 10 and the battery oil circuit 30. The water-oil heat exchanger 75 includes a warm water flow path 16 through which warm water flows and an insulating oil flow path 35 through which insulating oil flows, and performs heat exchange between the warm water and the insulating oil. The warm water flow rate adjustment valve 14 is a three-way valve that adjusts the flow rate of the warm water flowing through the heater core 13 and the flow rate of the warm water flowing through the warm water flow path 16 of the water-oil heat exchanger 75. The warm water flow rate adjustment valve 14 can switch between allowing and blocking the flow of warm water to the warm water flow path 16 of the water-oil heat exchanger 75.

[0021] When the warm water flow rate adjustment valve 14 allows warm water to flow into the warm water flow path 16, the heating circuit 10 and the battery oil circuit 30 are thermally connected via the water-oil heat exchanger 75. On the other hand, when the warm water flow rate adjustment valve 14 blocks the flow of warm water into the warm water flow path 16, the heating circuit 10 and the battery oil circuit 30 are thermally disconnected. Therefore, the warm water flow rate adjustment valve 14 and the water-oil heat exchanger 75 constitute a first switching circuit 19 that switches between the thermal connection and disconnection of the heating circuit 10 and the battery oil circuit 30.

[0022] The cooling circuit 20 is a circuit that circulates a refrigerant to cool the vehicle interior. The cooling circuit 20 includes a compressor 21, an air-cooled condenser 22, an evaporator 23, a refrigerant flow path 24 of a chiller 76, and pressure reducing valves 25 and 26.

[0023] The compressor 21 compresses the refrigerant flowing through the cooling circuit 20. The air-cooled condenser 22 is a heat exchanger that exchanges heat between the outside air and the compressed refrigerant. The air-cooled condenser 22 cools the compressed refrigerant, whose temperature has risen, with the outside air, condensing it into a liquid. The pressure reducing valve 25 reduces the pressure of the compressed liquid to make it a low-temperature refrigerant. The evaporator 23 is a heat exchanger between the refrigerant, which has been cooled by the pressure reduction, and the air inside the vehicle. The refrigerant evaporates inside the evaporator 23, absorbing heat from the air inside the vehicle and cooling the air inside the vehicle. The chiller 76 is positioned across the cooling circuit 20 and the battery oil circuit 30. The chiller 76 has a refrigerant flow path 24 through which the refrigerant flows and an insulating oil flow path 32 through which insulating oil flows, and heat exchange takes place between the refrigerant and the insulating oil. The pressure reducing valve 26, like the pressure reducing valve 25, reduces the pressure of the compressed liquid to make it a low-temperature refrigerant. The reduced-pressure, low-temperature refrigerant flows through the refrigerant passage 24 of the chiller 76.

[0024] The battery oil circuit 30 is a circuit that circulates insulating oil to cool the battery 77. The battery oil circuit 30 includes an insulating oil pump 31, an insulating oil passage 32 for the chiller 76, an insulating oil passage 33 for the battery 77, an insulating oil passage 34 for the oil-oil heat exchanger 74, an insulating oil passage 35 for the water-oil heat exchanger 75, and an oil pan 46.

[0025] The insulating oil pump 31 circulates insulating oil in the battery oil circuit 30. As previously explained, the chiller 76 is positioned across the battery oil circuit 30 and the cooling circuit 20. The chiller 76 has an insulating oil passage 32 and a refrigerant passage 24 inside, and heat exchange takes place between the insulating oil and the refrigerant. Therefore, the battery oil circuit 30 is thermally connected to the cooling circuit 20 by the chiller 76.

[0026] The battery 77 supplies power to the motor generator 70 for vehicle propulsion. The battery 77 has an insulating oil passage 33 through which insulating oil flows. The battery 77 is cooled or heated by the flow of insulating oil through the insulating oil passage 33. The battery 77 is fitted with a battery temperature sensor 37 that detects the temperature of the battery 77. The oil-oil heat exchanger 74 is positioned across the battery oil circuit 30 and the motor oil circuit 40. The oil-oil heat exchanger 74 has an insulating oil passage 34 through which insulating oil flows and a cooling oil passage 43 through which cooling oil flows, and performs heat exchange between the insulating oil and the cooling oil. As previously described, the water-oil heat exchanger 75 has an insulating oil passage 35 and a hot water passage 16 inside, and performs heat exchange between the insulating oil and hot water. The oil pan 36 stores the insulating oil that circulates in the battery oil circuit 30.

[0027] The motor oil circuit 40 is a circuit that circulates the cooling oil for the motor generator 70. The motor oil circuit 40 includes a cooling oil pump 41, a cooling oil flow control valve 42, a cooling oil passage 43 for the oil-oil heat exchanger 74, a cooling oil passage 44 for the oil cooler 71, a cooling oil passage 45 for the motor generator 70, an oil pan 46, and an oil-oil heat exchanger bypass passage 47.

[0028] The cooling oil pump 41 circulates cooling oil to the motor oil circuit 40. As previously described, the oil-oil heat exchanger 74 is positioned across the motor oil circuit 40 and the battery oil circuit 30, and contains an insulating oil passage 34 and a cooling oil passage 43, performing heat exchange between the insulating oil and the cooling oil. The cooling oil flow control valve 42 is a three-way valve positioned between the cooling oil pump 41 and the cooling oil passage 43 of the oil-oil heat exchanger 74, and adjusts the flow rate of cooling oil through the cooling oil passage 43 of the oil-oil heat exchanger 74. The oil-oil heat exchanger bypass passage 47 connects the cooling oil flow control valve 42 to the downstream side of the cooling oil passage 43 so as to bypass the cooling oil passage 43 of the oil-oil heat exchanger 74. The cooling oil flow control valve 42 can switch the flow of cooling oil to and from the cooling oil passage 43 of the oil-oil heat exchanger 74. When the cooling oil flow control valve 42 blocks the flow of cooling oil to the cooling oil passage 43, the cooling oil does not flow through the cooling oil passage 43 of the oil-oil heat exchanger 74, but instead flows through the oil-oil heat exchanger bypass passage 47.

[0029] When cooling oil is allowed to flow through the cooling oil passage 43 of the oil-oil heat exchanger 74 by the cooling oil flow control valve 42, the motor oil circuit 40 is thermally connected to the battery oil circuit 30 via the oil-oil heat exchanger 74. On the other hand, when the flow of cooling oil through the cooling oil passage 43 of the oil-oil heat exchanger 74 is blocked by the cooling oil flow control valve 42, the motor oil circuit 40 is thermally disconnected from the battery oil circuit 30. Therefore, the cooling oil flow control valve 42 and the oil-oil heat exchanger 74 constitute a second switching circuit 49 that switches between thermal connection and disconnection between the motor oil circuit 40 and the battery oil circuit 30.

[0030] The oil cooler 71 is positioned across the motor oil circuit 40 and the motor cooling water circuit 50. The oil cooler 71 has a cooling oil passage 44 through which cooling oil flows and a cooling water passage 55 through which cooling water flows, and heat exchange takes place between the cooling oil and the cooling water. The oil cooler 71 cools the cooling oil that has become hot by passing it through the cooling oil passage 45 of the motor generator 70. In this way, the motor oil circuit 40 is thermally connected to the motor cooling water circuit 50 by the oil cooler 71.

[0031] The motor-generator 70 for vehicle drive is the power source that drives the vehicle 200. The motor-generator 70 is equipped with a cooling oil passage 45 through which cooling oil flows. The cooling oil flows through the cooling oil passage 45 and through the inside of the motor-generator 70, cooling the stator, rotor, etc. As mentioned above, the cooling oil, whose temperature has risen after flowing through the cooling oil passage 45, is cooled by the oil cooler 71. The oil pan 46 stores the cooling oil. A cooling oil temperature sensor 48 for detecting the temperature of the cooling oil is installed in the cooling oil piping between the cooling oil pump 41 and the cooling oil flow control valve 42.

[0032] The motor cooling water circuit 50 is a circuit that circulates cooling water to the motor generator 70, the power distribution unit 72, and the power control unit 73. The motor cooling water circuit 50 includes a cooling water pump 51, a cooling water passage 52 for the power distribution unit 72, a cooling water passage 53 for the power control unit 73, a cooling water passage 54 for the motor generator 70, a cooling water passage 55 for the oil cooler 71, a cooling water flow control valve 56, a radiator 57, and a radiator bypass passage 58.

[0033] The cooling water pump 51 circulates cooling water in the motor cooling water circuit 50. The power distribution unit 72 includes a voltage converter and converts high-voltage DC power supplied from the battery 77 into DC power of multiple voltages, and supplies the converted DC power of multiple voltages to each device. The power distribution unit 72 is cooled by the cooling water flowing through the cooling water passage 52. The power control unit 73 adjusts the power supplied to the motor generator 70. The power control unit 73 includes multiple semiconductor elements. The cooling water passage 53 is positioned in contact with these semiconductor elements and cools them by the flow of cooling water through it. The motor generator 70 is the power source that drives the vehicle 200, and the motor generator 70 is cooled by the flow of cooling water through the cooling water passage 54 located inside it. As explained earlier, the oil cooler 71 is positioned across the motor cooling water circuit 50 and the motor oil circuit 40, and has a cooling oil passage 44 and a cooling water passage 55 inside, performing heat exchange between the cooling oil and the cooling water. The radiator 57 is a heat exchanger that performs heat exchange between the outside air and the cooling water. The radiator 57 cools the cooling water by releasing the heat from the heated cooling water into the outside air. The cooling water flow control valve 56 is a three-way valve located upstream of the radiator 57 that adjusts the flow rate of the cooling water passing through the radiator 57. The radiator bypass passage 58 connects the cooling water flow control valve 56 and the downstream side of the radiator 57 so as to bypass the radiator 57.

[0034] The control device 60 is a computer that includes a CPU 61 for information processing and a memory 62 for storing control programs and control data. The battery temperature sensor 37 and the cooling oil temperature sensor 48 are connected to the control device 60, and the data detected by the battery temperature sensor 37 and the cooling oil temperature sensor 48 are input to the control device 60.

[0035] The hot water pump 11, high-pressure electric heater 12, hot water flow control valve 14, compressor 21, insulating oil pump 31, cooling oil pump 41, cooling oil flow control valve 42, cooling water pump 51, and cooling water flow control valve 56 are connected to the control device 60 and operate according to commands from the control device 60.

[0036] The control device 60 is connected to the drive control device 65, which controls the operation of the motor generator 70, the power distribution unit 72, and the power control unit 73, and exchanges data with them. The drive control device 65 is a computer that includes a CPU 66, which is a processor that performs information processing, and a memory 67 that stores control programs and control data.

[0037] Next, the basic operation of the vehicle thermal management system 100 configured as described above will be explained.

[0038] When heating the passenger compartment, a high-pressure electric heater 12 heats hot water, and the hot water flow control valve 14 is switched to the heater core side to allow the heated hot water to flow through the heater core 13, which then heats the air inside the passenger compartment.

[0039] When cooling the passenger compartment, the compressor 21 compresses the refrigerant, the air-cooled condenser 22 condenses the refrigerant into a high-pressure liquid, the pressure reducing valve 25 expands the refrigerant to a low temperature, and the evaporator 23 evaporates the refrigerant, removing heat from the passenger compartment air and cooling the air inside the compartment.

[0040] When the vehicle 200 is running on the motor generator 70, cooling water is circulated through the motor cooling water circuit 50 to cool the motor generator 70, the power distribution unit 72, and the power control unit 73. In addition, the cooling oil flow rate control valve 42 is switched to the oil-oil heat exchanger bypass side, and cooling oil is circulated through the cooling oil passage 45 of the motor generator 70 to cool the stator and rotor inside the motor generator 70. The cooling oil whose temperature has risen after circulating through the cooling oil passage 45 of the motor generator 70 is cooled by the oil cooler 71. The cooling water whose temperature has risen after circulating through the cooling water passage 52 of the power distribution unit 72, the cooling water passage 53 of the power control unit 73, the cooling water passage 54 of the motor generator 70, and the cooling water passage 55 of the oil cooler 71 is cooled by the radiator 57.

[0041] If the temperature of the battery 77 rises due to charging or discharging, the cooling circuit 20 supplies a low-temperature refrigerant to the chiller 76, and the chiller 76 exchanges heat with the low-temperature refrigerant to cool the insulating oil. The cooled insulating oil is then passed through the insulating oil passage 33 of the battery 77, thereby cooling the battery 77.

[0042] Next, referring to Figures 2 and 3, the operation of the vehicle thermal management system 100 when the temperature of the battery 77 is low and the battery 77 needs to be warmed up will be explained. Note that "MG" in Figures 2 and 3 refers to the motor generator 70.

[0043] As shown in step S101 of Figure 2, the CPU 61 of the control device 60 detects the temperature of the battery 77 using the battery temperature sensor 37 and determines whether it is at the required warm-up temperature. Here, the required warm-up temperature may be, for example, less than 0°C or even lower. The required warm-up temperature may also be changed depending on the remaining capacity of the battery 77. The CPU 61 of the control device 60 repeats step S101 in Figure 1 until it determines YES, and waits until the temperature of the battery 77 reaches the required warm-up temperature.

[0044] If the CPU 61 of the control device 60 determines YES in step S101 in Figure 1, it proceeds to step S102 in Figure 1 to determine whether the vehicle 200 is being driven by the motor generator 70. This determination may be made, for example, by receiving information from the drive control device 65 that the start switch of the vehicle 200 is ON, or by receiving a drive signal from the drive control device 65 for the motor generator 70.

[0045] If the CPU 61 of the control device 60 determines YES in step S102 in Figure 2, it proceeds to step S103 in Figure 2. In step S103 in Figure 2, the CPU 61 of the control device 60 obtains the temperature of the coolant from the coolant temperature sensor 48 and determines whether it is above a predetermined threshold. Here, the predetermined threshold is a temperature higher than the required warm-up temperature of the battery 77, and a temperature at which the coolant can heat the insulating oil flowing through the battery 77. The predetermined threshold may be, for example, 10°C or around 30°C.

[0046] If the CPU 61 of the control device 60 determines YES in step S103 in Figure 2, it proceeds to step S104 in Figure 2. In step S104 in Figure 2, the CPU 61 of the control device 60 switches the cooling oil flow control valve 42 to the oil-oil heat exchanger side, allowing the cooling oil to flow through the cooling oil passage 43 of the oil-oil heat exchanger 74. The CPU 61 of the control device 60 also switches the cooling water flow control valve 56 to the radiator side, allowing the cooling water to flow through the radiator 57. The CPU 61 of the control device 60 also switches the hot water flow control valve 14 to the heater core side, blocking the flow of hot water to the hot water passage 16 of the water-oil heat exchanger 75.

[0047] In this way, the CPU 61 of the control device 60 thermally connects the motor oil circuit 40 and the battery oil circuit 30 by the first switching circuit 19, and heats the insulating oil with the heat generated by the motor generator 70. Then, the heated insulating oil is circulated to the battery oil circuit 30 to raise the temperature of the battery 77. On the other hand, the CPU 61 of the control device 60 thermally disconnects the battery oil circuit 30 and the heating circuit 10 by the second switching circuit 49. In addition, the cooling water that has risen in temperature after passing through the cooling water passage 54 of the motor generator 70 is cooled by the radiator 57. As a result, as shown in step S105 of Figure 2, when the vehicle 200 is running on the motor generator 70 and the cooling oil temperature is above a predetermined threshold, the CPU 61 of the control device 60 cools the motor generator 70 while raising the temperature of the battery 77 with the heat from the motor generator 70.

[0048] Then, in step S106 of Figure 2, the CPU 61 of the control device 60 detects the temperature of the battery 77 using the battery temperature sensor 37 and determines whether the temperature of the battery 77 has reached the warm-up completion temperature. Here, the warm-up completion temperature can be set freely, but for example, it may be set to around 10°C.

[0049] Then, if the CPU 61 of the control device 60 determines YES in step S106 in Figure 2, it stops the temperature rise of the battery 77.

[0050] On the other hand, if the CPU 61 of the control device 60 determines NO in step S102 in Figure 2, it proceeds to step S107 in Figure 2 to determine whether there is a request for heating in the vehicle compartment. This determination may be made, for example, by checking whether a signal indicating that the heating switch of the air conditioning system is ON has been input. If the CPU 61 of the control device 60 determines YES in step S107 in Figure 2, it proceeds to step S108 in Figure 2 to increase the output of the high-voltage electric heater 12 to the sum of the output required for heating and the output required to raise the temperature of the battery 77. If the sum of the outputs exceeds the maximum output of the high-voltage electric heater 12, the output of the high-voltage electric heater 12 is increased to the maximum output.

[0051] On the other hand, if the CPU 61 of the control device 60 determines NO in step S107 in Figure 2, it proceeds to step S109 in Figure 2 and turns on the high-voltage electric heater 12. Then, it sets the output of the high-voltage electric heater 12 to the output required to raise the temperature of the battery 77.

[0052] In step S110 of Figure 2, the CPU 61 of the control device 60 switches the cooling oil flow control valve 42 to the oil-oil heat exchanger bypass side, blocking the flow of cooling oil to the cooling oil passage 43 of the oil-oil heat exchanger 74. In this case, the cooling oil flows through the oil-oil heat exchanger bypass passage 47. The CPU 61 of the control device 60 also switches the hot water flow control valve 14 to the water-oil heat exchanger side, allowing hot water to flow through the hot water passage 16 of the water-oil heat exchanger 75. If there is a heating request, the CPU 61 of the control device 60 adjusts the opening of the hot water flow control valve 14 so that the hot water needed for heating flows through the heater core 13 and any excess hot water flows through the hot water passage 16 of the water-oil heat exchanger 75.

[0053] In this way, the CPU 61 of the control device 60 thermally connects the motor oil circuit 40 and the heating circuit 10 by the first switching circuit 19, and heats the insulating oil with hot water heated by the high-voltage electric heater 12. Then, the heated insulating oil is circulated to the battery oil circuit 30 to raise the temperature of the battery 77. On the other hand, the CPU 61 of the control device 60 thermally disconnects the battery oil circuit 30 and the motor oil circuit 40 by the second switching circuit 49. In this way, as shown in step S111 of Figure 2, when the vehicle 200 is stopped, the CPU 61 of the control device 60 raises the temperature of the battery 77 with the heat from the high-voltage electric heater 12.

[0054] Then, in step S112 of Figure 2, the CPU 61 of the control device 60 detects the temperature of the battery 77 using the battery temperature sensor 37 and determines whether the temperature of the battery 77 has reached the warm-up completion temperature. If the CPU 61 of the control device 60 determines YES in step S112 of Figure 2, it stops the heating of the battery 77.

[0055] On the other hand, if the CPU 61 of the control device 60 determines NO in step S103 in Figure 2, it proceeds to step S113 in Figure 3. In step S113 in Figure 3, the CPU 61 of the control device 60 switches the cooling oil flow control valve 42 to the oil-oil heat exchanger bypass side. The CPU 61 of the control device 60 also switches the cooling water flow control valve 56 to the radiator bypass side. The CPU 61 of the control device 60 also outputs a command to the drive control device 65 to perform heat generation increase control, which increases the loss of the motor generator 70 and increases its self-heating. As a result, the drive control device 65 executes the heat generation increase control of the motor generator 70. The CPU 61 of the control device 60 may also increase the flow rate of the cooling oil pump 41.

[0056] Here, various control methods can be applied to increase the heat generation, which increases the self-heating by increasing the losses of the motor generator 70. For example, the voltage applied to the inverter may be lowered, and the inverter may be controlled by square wave control and weakening magnetic field control so that the current is larger compared to sinusoidal control.

[0057] In this way, the CPU 61 of the control device 60 thermally isolates the motor oil circuit 40 and the battery oil circuit 30 using the second switching circuit 49. The cooling oil then heats up due to the self-heating of the motor generator 70. At this time, the cooling water that has heated up by passing through the cooling water passage 54 of the motor generator 70 circulates back to the cooling water passage 54 of the motor generator 70 via the radiator bypass passage 58, without passing through the radiator 57. Therefore, the heat generated by the self-heating of the motor generator 70 can effectively raise the temperature of the cooling oil. Furthermore, if the CPU 61 of the control device 60 increases the flow rate of the cooling oil pump 41 at this time, the amount of heat transferred from the cooling oil of the motor generator 70 to the insulating oil increases, and the heating rate of the insulating oil and battery 77 can be increased.

[0058] In step S114 of Figure 3, the CPU 61 of the control device 60 determines whether there is a heating request, similar to steps S107 to S108 in Figure 2. If it determines YES in step S114 of Figure 3, it increases the output of the high-voltage electric heater 12 in step S115 of Figure 3. If it determines NO in step S114 of Figure 3, it turns on the high-voltage electric heater 12 in step S116 of Figure 3.

[0059] In step S117 of Figure 3, the CPU 61 of the control device 60 switches the hot water flow control valve 14 to the water-oil heat exchanger side, allowing hot water to flow through the hot water passage 16 of the water-oil heat exchanger 75. Furthermore, as explained earlier in step S104 of Figure 2, when there is a heating request, the CPU 61 of the control device 60 adjusts the opening of the hot water flow control valve 14 to allow the necessary hot water for heating to flow through the heater core 13, and to allow any excess hot water to flow through the hot water passage 16 of the water-oil heat exchanger 75.

[0060] In this way, the CPU 61 of the control device 60 thermally connects the heating circuit 10 and the battery oil circuit 30 via the first switching circuit 19. Then, as shown in step S118 of Figure 3, the CPU 61 of the control device 60 raises the temperature of the battery 77 using the heat from the high-voltage electric heater 12.

[0061] Then, in step S119 of Figure 3, the CPU 61 of the control device 60 detects the temperature of the coolant using the coolant temperature sensor 48 and determines whether the temperature of the coolant is above a predetermined threshold and whether the insulating oil can be heated by the coolant. If the CPU 61 of the control device 60 determines NO in step S119 of Figure 3, it proceeds to step S120 of Figure 3 to determine whether the temperature of the battery 77 has reached the warm-up completion temperature. If the CPU 61 of the control device 60 determines NO in step S120 of Figure 3, it returns to step S118 of Figure 3 and continues to raise the temperature of the battery 77 using the heat from the high-voltage electric heater 12.

[0062] On the other hand, if the CPU 61 of the control device 60 determines YES in step S120 in Figure 3, it stops the warm-up of the battery 77.

[0063] If the CPU 61 of the control device 60 determines YES in step S119 in Figure 3, it determines that the insulating oil can now be heated by the cooling oil and proceeds to step S121 in Figure 3. In step S121 in Figure 3, the CPU 61 of the control device 60 switches the cooling oil flow control valve 42 to the oil-oil heat exchanger side and allows the cooling oil to flow through the cooling oil passage 43 of the oil-oil heat exchanger 74. The CPU 61 of the control device 60 also outputs a command to the drive control device 65 to stop the heat generation increase control of the motor generator 70. As a result, the drive control device 65 stops the heat generation increase control of the motor generator 70. The CPU 61 of the control device 60 also switches the cooling water flow control valve 56 to the radiator side and allows the cooling water to flow through the radiator 57.

[0064] In this way, the CPU 61 of the control device 60 thermally connects the battery oil circuit 30 and the motor oil circuit 40 by the second switching circuit 49. In addition, the heating circuit 10 and the battery oil circuit 30 are maintained to be thermally connected by the first switching circuit 19. As a result, as shown in step S122 of Figure 3, the battery 77 is heated by the heat from the high-voltage electric heater 12 and the motor generator 70.

[0065] In step S123 of the control device 60, the CPU 61 detects the temperature of the battery 77 using the battery temperature sensor 37 and determines whether the temperature of the battery 77 is above the heater heating stop temperature. Here, the heater heating stop temperature can be freely set within the range of above the required warm-up temperature of the battery 77 and below the warm-up completion temperature, but it may be set to, for example, about 5°C.

[0066] The CPU 61 of the control device 60 continues to raise the temperature of the battery 77 using the heat from the high-voltage electric heater 12 and the motor generator 70, as shown in step S122 of Figure 3, until it determines YES in step S123 of Figure 3. If the CPU 61 of the control device 60 determines YES in step S123 of Figure 3, it proceeds to step S124 of Figure 3.

[0067] The CPU 61 of the control device 60 stops the high-voltage electric heater 12 in step S124 of Figure 3 if there is no heating request, and if there is a heating request, it reduces the output of the high-voltage electric heater 12 to the output required for heating and proceeds to step S125 of Figure 3.

[0068] In step S125 of Figure 3, the CPU 61 of the control device 60 maintains the cooling oil flow control valve 42 on the oil-oil heat exchanger side and switches the hot water flow control valve to the heater core side. In this way, the CPU 61 of the control device 60 ensures that the battery oil circuit 30 and the motor oil circuit 40 are thermally connected by the second switching circuit 49, and that the battery oil circuit 30 and the heating circuit 10 are thermally disconnected by the first switching circuit 19. Then, as shown in step S126 of Figure 3, the CPU 61 of the control device 60 raises the temperature of the battery 77 using the heat from the motor generator 70. When the temperature of the battery 77 reaches the warm-up completion temperature, the CPU 61 determines YES in step S127 of Figure 3 and stops raising the temperature of the battery 77.

[0069] As explained above, when the vehicle 200 is stopped, the vehicle thermal management system 100 thermally connects the heating circuit 10 and the battery oil circuit 30 by the first switching circuit 19 and raises the temperature of the battery 77 with the heat of the high-voltage electric heater 12, so that the battery 77 can be heated even when the vehicle 200 is stopped. This makes it possible to increase the rate at which the battery 77 heats up in low-temperature environments. Furthermore, when the vehicle 200 is running on the motor generator 70, the motor oil circuit 40 and the battery oil circuit 30 are thermally connected by the second switching circuit 49 and the battery 77 is heated with the heat of the motor generator 70, so that the battery 77 can be heated up efficiently.

[0070] Furthermore, when the temperature of the coolant oil of the motor generator 70 is low, the vehicle thermal management system 100 thermally connects the heating circuit 10 and the battery oil circuit 30 using the first switching circuit 19 to raise the temperature of the battery 77 with the heat of the high-voltage electric heater 12. When the temperature of the coolant oil reaches a predetermined threshold or higher, the motor oil circuit 40 and the battery oil circuit 30 are thermally connected using the second switching circuit 49 to raise the temperature of the battery 77 with the heat of the high-voltage electric heater 12 and the heat of the motor generator 70. When the temperature of the battery 77 reaches a temperature above the heater heating stop temperature, the heating circuit 10 and the battery oil circuit 30 are thermally shut off using the first switching circuit 19, and the battery 77 is raised with the heat of the motor generator 70. This allows for a high rate of temperature rise of the battery 77 in low-temperature environments and efficient temperature rise of the battery 77.

[0071] Furthermore, the vehicle thermal management system 100 cuts off the flow of cooling water to the radiator 57 when the vehicle 200 is running on the motor generator 70 and the temperature of the cooling oil is below a predetermined threshold, thereby increasing the rate at which the temperature of the cooling oil in the motor generator 70 rises. This allows the rate at which the battery 77 heats up to a high temperature in low-temperature environments.

[0072] Furthermore, the vehicle thermal management system 100 increases the self-heating amount of the motor generator 70 when the vehicle 200 is running on the motor generator 70 and the temperature of the cooling oil is below a predetermined threshold, thereby increasing the rate at which the temperature of the cooling oil of the motor generator 70 rises. This allows the rate at which the battery 77 heats up to a higher temperature in low-temperature environments. At this time, by increasing the flow rate of the cooling oil pump 41, the heat generated by the motor generator 70 can be effectively transferred to the insulating oil. This further increases the rate at which the insulating oil and the battery 77 heat up to a higher temperature.

[0073] In the above explanation, the second switching circuit 49 was described as consisting of an oil-oil heat exchanger 74 and a cooling oil flow control valve 42, but it is not limited to this. For example, instead of the oil-oil heat exchanger 74, the cooling oil piping may be passed through the insulating oil pan 36, and the heat exchange between the cooling oil and insulating oil may be performed within the insulating oil pan 36. Alternatively, instead of the oil-oil heat exchanger 74, the insulating oil piping may be passed through the cooling oil pan 46, and the heat exchange between the cooling oil and insulating oil may be performed within the cooling oil pan 46. [Explanation of Symbols]

[0074] 10 Heating circuit, 11 Hot water pump, 12 High-pressure electric heater, 13 Heater core, 14 Hot water flow control valve, 16 Hot water flow path, 19 First switching circuit, 20 Cooling circuit, 21 Compressor, 22 Air-cooled condenser, 23 Evaporator, 24 Refrigerant flow path, 25, 26 Pressure reducing valve, 30 Battery oil circuit, 31 Insulating oil pump, 32-35 Insulating oil flow path, 36, 46 Oil pan, 37 Battery temperature sensor, 40 Motor oil circuit, 41 Cooling oil pump, 42 Cooling oil flow control valve, 43-45 Cooling oil flow path, 47 Oil-oil heat exchanger bypass flow path, 48 Cooling oil temperature sensor, 49 Second switching circuit, 50 Motor cooling water circuit, 51 Cooling water pump, 52-55 Cooling water flow path, 56 Cooling water flow control valve, 57 Radiator, 58 Radiator bypass flow path, 60 Control device, 61, 66 CPU, 62, 67 Memory, 65 Drive control device, 70 Motor generator, 71 Oil cooler, 72 Power distribution unit, 73 Power control unit, 74 Oil-oil heat exchanger, 75 Water-oil heat exchanger, 76 Chiller, 77 Battery, 100 Vehicle thermal management system, 200 Vehicle.

Claims

1. A thermal management system for vehicles, A heating circuit that circulates hot water heated by an electric heater to heat the vehicle interior, A cooling circuit that circulates a refrigerant to cool the passenger compartment, A battery oil circuit is thermally connected to the aforementioned cooling circuit and circulates insulating oil to cool the battery, A motor oil circuit that circulates cooling oil for the motor generator used to drive the vehicle, A first switching circuit that switches between thermal connection and disconnection between the heating circuit and the battery oil circuit, A second switching circuit that switches between thermal connection and disconnection between the motor oil circuit and the battery oil circuit, The system comprises a control device that adjusts the operation of the first switching circuit and the second switching circuit, The control device is When the vehicle is running on the motor generator, the first switching circuit thermally disconnects the heating circuit and the battery oil circuit, and the second switching circuit thermally connects the motor oil circuit and the battery oil circuit. When the vehicle is stopped, the first switching circuit thermally connects the heating circuit and the battery oil circuit, and the second switching circuit thermally disconnects the motor oil circuit and the battery oil circuit. A vehicle thermal management system characterized by the following features.

2. A vehicle thermal management system according to claim 1, The control device is When the vehicle is running on the motor generator and the temperature of the cooling oil is below a predetermined threshold, the first switching circuit thermally connects the heating circuit and the battery oil circuit, and the second switching circuit thermally disconnects the motor oil circuit and the battery oil circuit. Subsequently, when the temperature of the cooling oil exceeds a predetermined threshold, the second switching circuit thermally connects the motor oil circuit and the battery oil circuit. Subsequently, if the temperature of the battery exceeds the heater heating stop temperature, the first switching circuit thermally shuts off the heating circuit and the battery oil circuit. A vehicle thermal management system characterized by the following features.

3. A vehicle thermal management system according to claim 2, A motor cooling water circuit that circulates cooling water through the radiator to cool the motor generator, The system includes a cooling water flow control valve that adjusts the flow rate of the cooling water flowing through the radiator, The control device is When the vehicle is running on the motor generator and the temperature of the coolant is below a predetermined threshold, the coolant flow control valve blocks the flow of the coolant to the radiator. Subsequently, when the temperature of the cooling oil exceeds a predetermined threshold, the cooling water flow control valve is used to allow the cooling water to flow through the radiator. A vehicle thermal management system characterized by the following features.

4. A vehicle thermal management system according to claim 3, The motor oil circuit includes a cooling oil pump for circulating the cooling oil, The control device adjusts the operation of the motor generator and the cooling oil pump, When the vehicle is running on the motor-generator and the temperature of the coolant is below a predetermined threshold, the motor-generator's losses are increased to increase its self-heating capacity, and the flow rate of the coolant pump is increased. A vehicle thermal management system characterized by the following features.

5. A vehicle thermal management system according to any one of claims 1 to 4, The first switching circuit is, A water-oil heat exchanger that performs heat exchange between the hot water and the insulating oil, and heats the insulating oil with the hot water, The system includes a hot water flow control valve for adjusting the flow rate of the hot water that flows through the water-oil heat exchanger, The second switching circuit is, An oil-oil heat exchanger that performs heat exchange between the cooling oil and the insulating oil, and heats the insulating oil with the cooling oil, The system includes a cooling oil flow control valve for adjusting the flow rate of the cooling oil that flows through the oil heat exchanger, The control device is The heating circuit and the battery oil circuit are thermally connected by passing the hot water through the water-oil heat exchanger using the hot water flow control valve, and the heating circuit and the battery oil circuit are thermally isolated by blocking the flow of the hot water to the water-oil heat exchanger using the hot water flow control valve. The motor oil circuit and the battery oil circuit are thermally connected by passing the cooling oil through the oil-oil heat exchanger using the cooling oil flow control valve, and the motor oil circuit and the battery oil circuit are thermally isolated by blocking the flow of the cooling oil to the oil-oil heat exchanger using the cooling oil flow control valve. A vehicle thermal management system characterized by the following features.

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