Thermal management system, thermal management method, and computer device

Abstract

To properly perform thermal management of a wide range in a vehicle through a thermal management system of a simple structure.SOLUTION: A thermal management system comprises: a first flow channel 10 where a first coolant C1 flows to cool a power storage device (battery 12) mounted on a vehicle; a second flow channel 20 where a second coolant C2 flows to cool a drive unit (inverter 23, motor 24) causing the vehicle to travel; a third flow channel 30 where a third coolant C3 flows to be cooled by a refrigeration cycle; and a heat exchanger 50 which is connected with the first flow channel 10, the second flow channel 20, and the third flow channel 30 respectively. The first flow channel 10, the second flow channel 20, and the third flow channel 30 are formed independently from each other. The heat exchanger 50 is configured to perform heat exchange among the first coolant C1, the second coolant C2, and the third coolant C3.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a thermal management system, a thermal management method, and a computer device. [Background technology]

[0002] International Publication No. 2017 / 017867 (Patent Document 1) discloses a technology for cooling a battery using insulating oil. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2017 / 017867 Summary of the Invention [Problem to be solved by the invention]

[0004] It is possible to appropriately cool a battery (electricity storage device) according to the technology described in Patent Document 1. However, Patent Document 1 does not sufficiently consider how to appropriately perform wide-area thermal management of a vehicle (for example, thermal management of the entire vehicle) using a thermal management system with a simple structure.

[0005] The present disclosure has been made to solve the above-mentioned problems, and its purpose is to appropriately perform wide-area thermal management of a vehicle using a thermal management system with a simple structure. [Means for solving the problem]

[0006] According to an embodiment of a first aspect of the present disclosure, there is provided a thermal management system as follows. (Item 1) The thermal management system includes a first flow path through which a first refrigerant flows to cool an electric storage device mounted on a vehicle, a second flow path through which a second refrigerant flows to cool a drive device that runs the vehicle, a third flow path through which a third refrigerant cooled by a refrigeration cycle flows, and heat exchangers connected to the first flow path, the second flow path, and the third flow path, respectively. The first flow path, the second flow path, and the third flow path are formed independently of one another. The heat exchangers are configured to mutually exchange heat between the first refrigerant, the second refrigerant, and the third refrigerant.

[0007] According to the above configuration, the heat exchanger exchanges heat among the first, second, and third refrigerants, making it possible to cool the power storage device and the drive device using the third refrigerant cooled by the refrigeration cycle. Furthermore, since the first, second, and third flow paths are formed independently of each other, it becomes easier to individually adjust each flow path to an appropriate temperature. This makes it possible to appropriately manage the heat over a wide area of ​​the vehicle (for example, the heat management of the area including the power storage device and the drive device). Furthermore, since all of the first, second, and third refrigerants flow into a common heat exchanger and heat exchange among the first, second, and third refrigerants is performed by a single heat exchanger, the structure of the thermal management system is simplified and costs are reduced.

[0008] A vehicle equipped with the power storage device and drive device may be an xEV (exclusively referred to as an electric vehicle) that uses electric power as all or part of its power source. The drive device may function as a transaxle or powertrain for the vehicle. The drive device may include a motor that generates power to run the vehicle and a drive circuit (e.g., an inverter) that drives the motor using power supplied from the power storage device. Examples of xEVs include BEVs (electric vehicles), HEVs (hybrid electric vehicles), PHEVs (plug-in hybrid electric vehicles), and FCEVs (fuel cell electric vehicles).

[0009] The thermal management system described in the above paragraph 1 may have the configuration described in any one of paragraphs 2 to 6 below.

[0010] (Item 2) The thermal management system according to item 1 further has the following features. The thermal management system further includes an air conditioning device that conditions the air inside the vehicle using a refrigeration cycle. The first refrigerant is insulating oil. The second refrigerant is water or an aqueous solution. The third refrigerant is a refrigerant for air conditioning.

[0011] The first flow path, the second flow path, and the third flow path are separate from one another and do not communicate with one another. Therefore, different types of refrigerants can be used in the first flow path, the second flow path, and the third flow path, as described above. Moreover, in the above configuration, by using insulating oil as the first refrigerant that cools the power storage device, it becomes easier to accurately cool the power storage device while suppressing conduction in the power storage device. In addition, the drive unit can be cooled using coolant (water or aqueous solution), which is inexpensive and easy to handle. Furthermore, by using the refrigeration cycle of the air conditioner, it is not necessary to add a special refrigeration cycle (for example, a refrigeration cycle for thermal management) to the vehicle.

[0012] (Item 3) The thermal management system according to item 1 or 2 further has the following feature: The thermal management system further includes a first pump that circulates a first refrigerant through a first fluid circuit formed by the first flow path, a second pump that circulates a second refrigerant through a second fluid circuit formed by the second flow path, and a third pump that circulates a third refrigerant through a third fluid circuit formed by the third flow path.

[0013] According to the above configuration, the first flow path, the second flow path, and the third flow path are each individually provided with a pump, which makes it easier to control the circulation of the coolant in each flow path.

[0014] (Item 4) The thermal management system described in item 3 further has the following feature: the second flow path includes a first portion passing through the drive device, a second portion connecting from a first end of the first portion through the heat exchanger to a second end of the first portion, and a third portion connecting from the first end of the first portion to the second end of the first portion without passing through the heat exchanger. The thermal management system further includes a metering valve configured to adjust the ratio between the amount of the second refrigerant flowing through the second portion and the amount of the second refrigerant flowing through the third portion.

[0015] The above-mentioned metering valve adjusts the ratio between the amount of the second refrigerant flowing into the second section and the amount of the second refrigerant flowing into the third section, making it easier to control the cooling of the drive unit by the second refrigerant and the heat exchange between the second refrigerant and other refrigerants.

[0016] (Item 5) The thermal management system according to item 4 further has the following features: The metering valve is a three-way valve connected to each of the first part, the second part, and the third part.

[0017] According to the above configuration, it is possible to adjust the ratio between the amount of the second refrigerant flowing into the second section and the amount of the second refrigerant flowing into the third section using a single adjustment valve (three-way valve), without having to provide separate valves for adjusting the amount of the second refrigerant flowing into the second section and the amount of the second refrigerant flowing into the third section.

[0018] (Item 6) The thermal management system described in item 4 or 5 further has the following feature: The thermal management system further includes a first temperature sensor in the first fluid circuit that detects the temperature of the first refrigerant pressure-fed by the first pump after passing through the heat exchanger and the power storage device, a second temperature sensor in the second fluid circuit that detects the temperature of the second refrigerant pressure-fed by the second pump before passing through the drive device, and a control device that controls the metering valve using the detection values ​​of the first temperature sensor and the second temperature sensor.

[0019] According to the above configuration, the control device can more easily appropriately control the regulating valve based on the detected values ​​of the first temperature sensor and the second temperature sensor.

[0020] According to an embodiment of the second aspect of the present disclosure, there is provided a thermal management method as follows. (Item 7) The thermal management method is a method for managing the heat of a vehicle using the thermal management system according to any one of items 4 to 6, and includes the steps of: when a first condition regarding the state of the vehicle is met, operating all of the first pump, the second pump, and the third pump, and controlling the metering valve so that the second refrigerant flows to the second portion; and when the first condition is not met and a second condition regarding the state of the vehicle is met, stopping the third pump, operating each of the first pump and the second pump, and controlling the metering valve so that the second refrigerant flows to the second portion. When the first condition is not met and a third condition related to the vehicle status is met, the first pump, the second pump, and the third pump are all activated and the metering valve is controlled so that the second refrigerant does not flow to the second section; and when the first condition is not met and a fourth condition related to the vehicle status is met, the first pump is stopped and the second pump and the third pump are each activated and the metering valve is controlled so that the second refrigerant flows to the second section.

[0021] According to the above method, it is possible to change the manner of heat exchange in the heat exchanger depending on the vehicle conditions, which makes it easier to perform heat management appropriate for the vehicle conditions.

[0022] According to an embodiment of the third aspect of the present disclosure, there is provided a thermal management method as follows. (Clause 8) The thermal management method is a method for managing the heat of a vehicle using the thermal management system described in any one of clauses 4 to 6, and includes acquiring the temperature of a first refrigerant flowing into a heat exchanger, acquiring the temperature of a second refrigerant flowing into the heat exchanger, acquiring a required cooling index indicating the required degree of cooling of the storage device, determining a target value for the flow rate of the second refrigerant to the second section using the temperature of the first refrigerant, the temperature of the second refrigerant, and the required cooling index, and controlling the metering valve so that the amount of the second refrigerant flowing into the second section approaches the determined target value.

[0023] According to the above method, it becomes easier to adjust the heat balance (for example, the temperature difference) between the first refrigerant and the second refrigerant to an appropriate balance.

[0024] According to an embodiment of a fourth aspect of the present disclosure, there is provided a computer device as follows. (Item 9) The computer device includes a processor and a storage device that stores a program that causes the processor to execute the thermal management method described in item 7 or 8.

[0025] The above-described computer device suitably executes the above-described thermal management method. According to one aspect, there is provided a program for causing a computer to execute the thermal management method according to paragraph 7 or 8. In another aspect, there is provided a computer device for distributing the program. [Effects of the Invention]

[0026] According to the present disclosure, a thermal management system with a simple structure can appropriately manage the heat over a wide range of a vehicle. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a diagram illustrating a configuration of a thermal management system according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a diagram for explaining a control device of a thermal management system according to an embodiment of the present disclosure. [Figure 3] 3 is a flowchart illustrating a method for controlling a metering valve according to an embodiment of the present disclosure. [Figure 4] 3 is a flowchart illustrating a pump control method according to an embodiment of the present disclosure. [Figure 5] FIG. 2 is a diagram illustrating a state of a thermal management system when three-fluid heat exchange is performed in an embodiment of the present disclosure. [Figure 6] 10A and 10B are diagrams illustrating a state of a thermal management system when two-fluid heat exchange is performed between a first flow path and a second flow path in the embodiment of the present disclosure. [Figure 7]FIG. 10 is a diagram illustrating a state of the thermal management system when two-fluid heat exchange is performed between the first and third flow paths in the embodiment of the present disclosure. [Figure 8] FIG. 10 is a diagram illustrating a state of the thermal management system when two-fluid heat exchange is performed between the second and third flow paths in the embodiment of the present disclosure. [Figure 9] 1 is a diagram illustrating an example of the configuration of a vehicle in which a thermal management system according to an embodiment of the present disclosure is implemented; DETAILED DESCRIPTION OF THE INVENTION

[0028] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present disclosure will be described in detail with reference to the accompanying drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals and their description will not be repeated.

[0029] Fig. 1 is a diagram showing the configuration of a thermal management system according to this embodiment. Referring to Fig. 1, the thermal management system according to this embodiment is applied to, for example, an electric vehicle (xEV). The thermal management system includes a first flow path 10, a second flow path 20, a third flow path 30, and a heat exchanger 50.

[0030] A first refrigerant C1 flows through the first flow path 10 to cool the battery 12. The battery 12 corresponds to an electric storage device mounted on a vehicle and functions as a power source for an electric vehicle. The first refrigerant C1 is a refrigerant for the battery. In this embodiment, insulating oil is used as the first refrigerant C1. By using insulating oil as the first refrigerant C1 that cools the battery 12, electrical conduction in the battery 12 is less likely to occur even in a configuration in which the first flow path 10 is formed to pass through the inside of the battery 12 to enhance the cooling effect. This makes it easier to accurately cool the battery 12 while suppressing electrical conduction (abnormalities related to electrical performance) in the battery 12.

[0031] A first pump 11 is provided in a first fluid circuit formed by the first flow path 10. The first pump 11 is configured to circulate a first refrigerant C1 through the first fluid circuit. In the first fluid circuit, a heat exchanger 50, a battery 12, and a temperature sensor 13 are provided in this order downstream from the first pump 11. The battery 12 is cooled by the first refrigerant C1 flowing through the first fluid circuit. The temperature sensor 13 detects a temperature T1 of the first refrigerant C1 at the outlet (after cooling) of the battery 12.

[0032] A second refrigerant C2 flows through the second flow path 20 to cool the drive unit that drives the vehicle. The drive unit includes an inverter 23 and a motor 24, and is configured to drive the vehicle using power supplied from the battery 12. The drive unit functions as a powertrain (PT) for the vehicle. The motor 24 functions as a traction motor. The second refrigerant C2 is a refrigerant for the powertrain. In this embodiment, water or an aqueous solution is used as the second refrigerant C2. The drive unit of the vehicle can be adequately cooled using cooling water, which is inexpensive and easy to handle.

[0033] A second pump 21 is provided in a second fluid circuit formed by the second flow path 20. The second pump 21 is configured to circulate a second refrigerant C2 through the second fluid circuit. The second flow path 20 includes a first portion 20a that passes through a drive device (inverter 23 and motor 24) of the vehicle, a second portion 20b that connects from a first end P1 of the first portion 20a to a second end P2 of the first portion 20a through a heat exchanger 50, and a third portion 20c (a bypass path) that connects from the first end P1 of the first portion 20a to the second end P2 of the first portion 20a without passing through the heat exchanger 50.

[0034] The fluid circuit (second fluid circuit A) formed by the first portion 20a and the second portion 20b includes, in this order downstream from the second pump 21, a temperature sensor 22, an inverter 23, a motor 24, a metering valve 25, a heat exchanger 50, and a radiator 26. On the other hand, the fluid circuit (second fluid circuit B) formed by the first portion 20a and the third portion 20c does not include the heat exchanger 50.

[0035] The second pump 21 is located in the first section 20a. The vehicle drive device (the inverter 23 and the motor 24) is also located in the first section 20a and is cooled by the second refrigerant C2 flowing through the first section 20a. The temperature sensor 22 is also located in the first section 20a (more specifically, between the second pump 21 and the inverter 23) and detects the temperature T21 of the second refrigerant C2 at the inlet (before cooling) of the vehicle drive device.

[0036] The metering valve 25 is located at a first end P1 of the first portion 20a. The metering valve 25 is, for example, a three-way valve. The metering valve 25 is configured to adjust the ratio between the amount of second refrigerant C2 flowing from the first portion 20a to the second portion 20b (hereinafter also referred to as the "non-bypass amount") and the amount of second refrigerant C2 flowing from the first portion 20a to the third portion 20c (hereinafter also referred to as the "bypass amount"). The metering valve 25 may be configured to change the ratio between the non-bypass amount and the bypass amount by changing at least one of the non-bypass amount and the bypass amount. In this embodiment, the larger the opening of the metering valve 25, the larger the non-bypass amount and the smaller the bypass amount (see FIG. 2, described later).

[0037] The radiator 26 is located in the first portion 20a and cools (dissipates heat from) the on-board components. When the temperature of the radiator 26 is low, the radiator 26 cools the second refrigerant C2. On the other hand, when the temperature of the radiator 26 is high, the radiator 26 is cooled by the second refrigerant C2. The radiator 26 may be cooled by wind (natural draft) generated when the vehicle is moving.

[0038] A third refrigerant C3, which is cooled by the refrigeration cycle of the on-board device, flows through the third flow path 30. In this embodiment, the third refrigerant C3 is cooled by the refrigeration cycle of the air conditioner. The air conditioner includes a condenser 32 and is configured to condition the interior of the vehicle using a refrigeration cycle (i.e., a cycle of evaporation, compression, condensation, and expansion strokes). In this way, by utilizing the refrigeration cycle of the air conditioner installed in the vehicle (e.g., xEV), it is not necessary to add a special refrigeration cycle (e.g., a refrigeration cycle for thermal management) to the vehicle. The third refrigerant C3 is an air conditioning refrigerant. Examples of air conditioning refrigerants include hydrofluorocarbon refrigerants such as R-134a, hydrofluoroolefin refrigerants such as R-1234yf, carbon dioxide (CO2) such as R744, and propane gas.

[0039] Heat exchange between the refrigeration cycle of the air conditioner and the third refrigerant C3 occurs via a condenser 32. The condenser 32 may also perform the condensation process in the refrigeration cycle. In this embodiment, the air conditioner further includes a compressor for the compression process, an expansion valve for the expansion process, an evaporator for the evaporation process, and a heat pump system (none of which are shown). A heat pump is a technology that collects heat and uses it as a large amount of thermal energy. The heat pump system can heat the interior of the vehicle, for example, by using heat in the air and waste heat from on-board components.

[0040] A third pump 31 is provided in a third fluid circuit formed by the third flow path 30. The third pump 31 is configured to circulate a third refrigerant C3 through the third fluid circuit. A condenser 32 and a heat exchanger 50 are provided in this order downstream from the third pump 31 in the third fluid circuit. The condenser 32 cools (dissipates heat from) the third refrigerant C3 flowing through the third fluid circuit. The condenser 32 may cool the third refrigerant C3 using wind from a condenser fan.

[0041] The heat exchanger 50 is connected to each of the first flow path 10, the second flow path 20, and the third flow path 30. The heat exchanger 50 functions as a three-fluid heat exchanger and is configured to exchange heat among the first refrigerant C1, the second refrigerant C2, and the third refrigerant C3. The heat exchanger 50 may be, for example, a plate-type heat exchanger. However, the heat exchange method is not limited to the plate-type method and may be any method, and one method selected from various known heat exchange methods depending on the purpose may be applied to the heat exchanger 50.

[0042] In this embodiment, the first flow path 10, the second flow path 20, and the third flow path 30 are formed independently of each other. The first flow path 10, the second flow path 20, and the third flow path 30 are separated from each other and do not communicate with each other. Therefore, different types of refrigerants can be used in the first flow path 10, the second flow path 20, and the third flow path 30.

[0043] The control device and the thermal management method of the thermal management system according to this embodiment will be described below with reference to FIGS.

[0044] FIG. 2 is a diagram for explaining a control device of the thermal management system according to this embodiment. Referring to FIG. 2 together with FIG. 1, the thermal management system according to this embodiment further includes an ECU (Electronic Control Unit) 500. The ECU 500 includes, for example, a computer and functions as a vehicle control device. The ECU 500 is configured to control a drive device of the vehicle (for example, the inverter 23). The ECU 500 includes a processor 501 and a storage device 502. The processor 501 may include a CPU (Central Processing Unit). The storage device 502 is configured to be able to save stored information. The storage device 502 stores programs as well as information used in the programs (for example, maps, mathematical formulas, and various parameters). In this embodiment, the processor 501 executes the programs stored in the storage device 502, thereby performing thermal management in the vehicle. The air conditioning device described above is also controlled by the ECU 500.

[0045] Each of the first pump 11, the second pump 21, and the third pump 31 is controlled by the ECU 500. By providing a pump (first pump 11, second pump 21, third pump 31) in each of the first flow path 10, the second flow path 20, and the third flow path 30, it becomes easier for the ECU 500 to control the circulation of the refrigerant (first refrigerant C1, second refrigerant C2, third refrigerant C3) in each flow path.

[0046] The metering valve 25 is controlled by the ECU 500. In this embodiment, a three-way valve connected to each of the first portion 20a, the second portion 20b, and the third portion 20c is employed as the metering valve 25. With this configuration, it is possible to adjust the ratio between the amount of second refrigerant C2 flowing into the second portion 20b and the amount of second refrigerant C2 flowing into the third portion 20c using a single metering valve (three-way valve), without having to provide separate valves for adjusting the amount of second refrigerant C2 flowing into the second portion 20b and the amount of second refrigerant C2 flowing into the third portion 20c.

[0047] In the graph shown in FIG. 2, lines L1 and L2 indicate an example of the characteristics of the metering valve 25. Line L1 indicates the relationship between the aperture of the metering valve 25 and the non-bypass amount (the amount of refrigerant flowing from the second flow path 20 to the heat exchanger 50). As indicated by line L1, the metering valve 25 increases the amount of second refrigerant C2 flowing from the first portion 20a to the second portion 20b (in the direction toward the heat exchanger 50) as its aperture increases. Line L2 indicates the relationship between the aperture of the metering valve 25 and the bypass amount. As indicated by line L2, the metering valve 25 decreases the amount of second refrigerant C2 flowing from the first portion 20a to the third portion 20c (in the direction avoiding the heat exchanger 50) as its aperture increases. In this way, the metering valve 25 is configured to decrease the ratio of the bypass amount to the non-bypass amount (= bypass amount / non-bypass amount) as its aperture increases. ECU 500 can adjust the ratio between the amount of second refrigerant C2 flowing through second portion 20b and the amount of second refrigerant C2 flowing through third portion 20c using metering valve 25. This configuration makes it easier to control the cooling of the drive device (inverter 23 and motor 24) by second refrigerant C2 and the heat exchange between second refrigerant C2 and other refrigerants (first refrigerant C1, third refrigerant C3) in heat exchanger 50.

[0048] In the first fluid circuit, temperature sensor 13 detects temperature T1 of first refrigerant C1 pumped by first pump 11 after passing through heat exchanger 50 and battery 12 (electricity storage device). Temperature sensor 13 corresponds to an example of a "first temperature sensor" according to the present disclosure. In addition, in first portion 20a of the second fluid circuit, temperature sensor 22 detects temperature T21 of second refrigerant C2 pumped by second pump 21 before passing through the drive device (inverter 23 and motor 24). Temperature sensor 22 corresponds to an example of a "second temperature sensor" according to the present disclosure. The detection values ​​of each of temperature sensors 13 and 22 are input to ECU 500 (control device). ECU 500 is configured to control metering valve 25 using the detection values ​​of each of temperature sensors 13 and 22.

[0049] 3 is a flowchart showing a method for controlling the metering valve 25 according to this embodiment. The processing shown in this flowchart is repeatedly executed by the ECU 500. "S" in the flowchart denotes a step.

[0050] 1, 2, and 3, in S11, ECU 500 acquires temperature T21 detected by temperature sensor 22. Subsequently, in S12, ECU 500 determines a loss in the vehicle power train (hereinafter referred to as "PT loss") from the operating state of the vehicle (e.g., the rotational speed and torque of motor 24) using, for example, a map.

[0051] Next, in S13, the ECU 500 calculates the flow rate of the second refrigerant C2 passing through the vehicle's drive system (inverter 23 and motor 24). In this embodiment, the second refrigerant C2 flowing through the first portion 20a passes through the vehicle's drive system to cool the drive system. The ECU 500 estimates the flow rate of the second refrigerant C2 passing through the vehicle's drive system, for example, based on a drive signal (e.g., duty ratio) for the second pump 21 and the opening degree of the metering valve 25. The flow rate obtained in S13 corresponds to the flow rate of the second refrigerant C2 passing through the vehicle's powertrain. Hereinafter, the flow rate obtained in S13 will be referred to as the "PT passing flow rate." However, if the cost disadvantage is acceptable, a flow meter may be provided in the first portion 20a to actually measure the PT passing flow rate.

[0052] Next, in S14, the ECU 500 determines the amount of temperature rise of the second refrigerant C2 due to the PT loss (hereinafter referred to as "ΔTloss"). Specifically, the ECU 500 obtains ΔTloss according to the PT loss and the PT passing flow rate, for example, using the map (lines L11 and L12) shown in FIG. 3. Basically, the greater the PT loss, the higher the temperature of the second refrigerant C2. However, the higher the PT passing flow rate (the flow rate at which the second refrigerant C2 passes through the powertrain), the more difficult it is for the temperature of the second refrigerant C2 to rise. In the above map, the degree to which the temperature of the second refrigerant C2 rises with an increase in PT loss (the slope of the graph: the ratio of the amount of temperature rise to the amount of increase in PT loss) is greater when the PT passing flow rate is low (line L12) than when the PT passing flow rate is high (line L11).

[0053] Next, in S15, the ECU 500 uses the temperature T21 obtained in S11 and ΔTloss obtained in S14 to determine the temperature T22 (FIG. 2) of the second refrigerant C2 flowing into the heat exchanger 50. Specifically, the ECU 500 sets the temperature T22 to, for example, the value obtained by adding ΔTloss to the temperature T21. Note that if the disadvantage in terms of cost is acceptable, a temperature sensor for actually measuring the temperature T22 may be provided in the second portion 20b.

[0054] Next, in S16, the ECU 500 acquires the temperature T1 detected by the temperature sensor 13. The temperature T1 corresponds to the temperature of the first refrigerant C1 flowing into the heat exchanger 50. Next, in S17, the ECU 500 calculates the temperature difference ΔT between the temperature T22 and the temperature T1. The temperature difference ΔT corresponds to the value obtained by subtracting the temperature T1 from the temperature T22.

[0055] Next, in S18, the ECU 500 acquires a requested cooling index indicating a requested degree of cooling of the battery 12. Specifically, the ECU 500 acquires the requested cooling index based on the temperature of the battery 12, the magnitude of the load on the battery 12 requested for driving the vehicle, and the magnitude of the load on the battery 12 requested by the user. The higher the current temperature of the battery 12 and the greater the requested load on the battery 12 (e.g., requested power), the larger the requested cooling index. A larger requested cooling index means that a greater degree of cooling of the battery 12 is requested by the thermal management system.

[0056] Next, in S19, the ECU 500 determines a target value (hereinafter referred to as "target flow rate V") of the flow rate of the second refrigerant C2 flowing through the second portion 20b (heat exchanger 50 side). Specifically, the ECU 500 obtains the target flow rate V according to the required cooling index and the temperature difference ΔT, for example, using the map (lines L21 and L22) shown in FIG. 3. The ECU 500 basically increases the target flow rate V as the required cooling index (required degree of cooling of the battery 12) increases. However, if the temperature difference ΔT is large and the amount of second refrigerant C2 flowing into the heat exchanger 50 is increased, the cooling effect of the first refrigerant C1 on the battery 12 decreases. For this reason, under the same required cooling index, the ECU 500 reduces the target flow rate V (line L21) when the temperature difference ΔT is large compared to the target flow rate V (line L22) when the temperature difference ΔT is small.

[0057] Next, in S20, the ECU 500 controls the metering valve 25 so that the amount of second refrigerant C2 flowing into the second portion 20b approaches the target flow rate V determined in S19. Specifically, the ECU 500 determines the target opening of the metering valve 25 according to the target flow rate V and temperature T22, for example, using the map (lines L31 and L32) shown in FIG. 3. Basically, the ECU 500 increases the opening of the metering valve 25 as the target flow rate V increases. However, if the opening of the metering valve 25 is increased when the temperature T22 of the second refrigerant C2 flowing into the heat exchanger 50 is high, the temperature of the first refrigerant C1 will increase (or will be less likely to decrease) due to heat exchange in the heat exchanger 50. Therefore, under the condition that the target flow rate V is the same, the ECU 500 sets the target opening of the metering valve 25 when the temperature T22 is high (line L31) to be smaller than the target opening of the metering valve 25 when the temperature T22 is low (line L32). Then, the ECU 500 controls the metering valve 25 to achieve the determined target opening. After the process of S20 is executed, the process returns to the first step (S11). The ECU 500 repeatedly executes the processes of S11 to S20 during three-fluid heat exchange (a period in which the first pump 11, the second pump 21, and the third pump 31 are all in operation as shown in FIG. 5), which will be described later. Through this control, the ECU 500 adjusts the opening of the metering valve 25 according to the state of the vehicle.

[0058] As described above, the thermal management method of this embodiment includes acquiring the temperature of the first refrigerant C1 flowing into the heat exchanger 50 (S16), acquiring the temperature of the second refrigerant C2 flowing into the heat exchanger 50 (S15), acquiring a required cooling index indicating the required degree of cooling of the battery 12 (power storage device) (S18), determining a target value (target flow rate V) of the flow rate of the second refrigerant C2 to the second portion 20b using the temperature of the first refrigerant C1, the temperature of the second refrigerant C2, and the required cooling index (S19), and controlling the metering valve 25 so that the amount of the second refrigerant C2 flowing into the second portion 20b approaches the determined target value (S20).

[0059] According to the above method, it becomes easier to adjust the heat balance (for example, the temperature difference ΔT) between the first refrigerant C1 and the second refrigerant C2 to an appropriate balance. Also, it becomes easier to control the heat exchange in the heat exchanger 50 so that the battery 12 is sufficiently cooled.

[0060] 4 is a flowchart showing a pump control method according to this embodiment. The process shown in this flowchart is repeatedly executed by ECU 500 that is started in response to a request from the user.

[0061] 1, 2, and 4, in S30, ECU 500 grasps the state of the vehicle. Specifically, ECU 500 determines whether or not there is a battery cooling request, a battery warming request, or a heating request for the vehicle. This determination is made, for example, in the following manner.

[0062] The ECU 500 determines whether or not there is a battery cooling request based on the requested cooling index. That is, the ECU 500 acquires the requested cooling index, which indicates the required degree of cooling of the battery 12, based on the vehicle status. The method of acquiring the requested cooling index is, for example, the same as that of S18 in FIG. 3 described above. Then, if the acquired requested cooling index exceeds a predetermined value (hereinafter referred to as a "first reference value"), the ECU 500 determines that "battery cooling is requested," and if the requested cooling index does not exceed the first reference value, the ECU 500 determines that "battery cooling is not requested."

[0063] Furthermore, the ECU 500 determines whether or not there is a battery temperature increase request based on the requested cooling index. A smaller requested cooling index means that the temperature increase rate of the battery 12 required by the thermal management system is larger. The requested cooling index may be expressed as a positive (+) value for the requested degree of cooling of the battery 12 and as a negative (-) value for the requested temperature increase rate of the battery 12. The ECU 500 determines that "battery temperature increase request exists" if the requested cooling index is below a predetermined value (hereinafter referred to as "second reference value"), and determines that "battery temperature increase request does not exist" if the requested cooling index is not below the second reference value. The second reference value is a value (a negative value) smaller than the first reference value. If the requested cooling index is equal to or greater than the second reference value and equal to or less than the first reference value, the ECU 500 determines that neither battery cooling request nor battery temperature increase request exists (no battery temperature control request).

[0064] The ECU 500 determines whether or not a heating request is made based on the requested heating index. That is, the ECU 500 acquires a requested heating index indicating the requested degree of heating inside the vehicle based on the vehicle status. Specifically, the ECU 500 acquires the requested heating index based on the vehicle interior temperature, the outside temperature, and the target air conditioning temperature. The target air conditioning temperature is set for the air conditioner, for example, by the user. The requested heating index increases as the current vehicle interior temperature decreases, the outside temperature decreases, and the target air conditioning temperature increases. A larger requested heating index means that a larger degree of heating inside the vehicle is requested of the thermal management system. The ECU 500 then determines that "heating is requested" if the requested heating index exceeds a predetermined value (hereinafter referred to as "third reference value"), and determines that "heating is not requested" if the requested heating index does not exceed the third reference value.

[0065] In steps S21 to S24 described below, the ECU 500 determines whether the first to fourth conditions are met based on the result of the determination (S30).

[0066] In S21, ECU 500 determines whether a predetermined first condition is met. Specific examples of the first condition will be described later. The first condition is a condition related to the vehicle status, and corresponds to the permission condition related to heat exchange in S31. If the first condition is met (YES in S21), ECU 500 executes three-fluid heat exchange in S31.

[0067] FIG. 5 is a diagram showing the state of the thermal management system when three-fluid heat exchange is performed. As shown in FIG. 5, in S31 of FIG. 4, the ECU 500 activates all of the first pump 11, the second pump 21, and the third pump 31 and controls the metering valve 25 so that the second refrigerant C2 flows through the second section 20b (including the heat exchanger 50). Specifically, the ECU 500 controls the metering valve 25 through a series of processes shown in FIG. 4. As a result, in the heat exchanger 50, heat is exchanged between the first flow path 10 (first refrigerant C1), the second flow path 20 (second refrigerant C2), and the third flow path 30 (third refrigerant C3) (see FIG. 1). This three-fluid heat exchange allows the battery 12, along with the vehicle's drive system (inverter 23 and motor 24), to be cooled by at least one of the refrigeration cycle of the air conditioner (third refrigerant C3) and the radiator 26 (second refrigerant C2). During the three-fluid heat exchange, the heat pump system of the air conditioner can heat the interior of the vehicle. More specifically, the heat pump system can heat the interior of the vehicle by utilizing at least one of the heat absorbed from the outside air, the waste heat from the battery, and the waste heat from the powertrain. Furthermore, during the three-fluid heat exchange, the heat balance between the first refrigerant C1 and the second refrigerant C2 is adjusted by repeatedly executing the processes of S11 to S20 in FIG. 3.

[0068] The first condition (S21 in FIG. 4) according to this embodiment is satisfied when both "battery cooling request present" and "heating request present" are satisfied, and is not satisfied when neither is satisfied. Furthermore, when only "battery cooling request present" of "battery cooling request present" and "heating request present" is satisfied, the first condition is satisfied if three-fluid heat exchange (see FIG. 5) is the most efficient battery cooling method compared to other methods (e.g., a battery cooling method using two-fluid heat exchange, which will be described later), but the first condition is not satisfied if there is another battery cooling method that is more efficient than three-fluid heat exchange. Furthermore, when only "heating request present" of "battery cooling request present" and "heating request present" is satisfied, the first condition is satisfied if three-fluid heat exchange is the most efficient heating method compared to other methods (e.g., a heating method using two-fluid heat exchange, which will be described later), but the first condition is not satisfied if there is another heating method that is more efficient than three-fluid heat exchange.

[0069] The ECU 500 may determine the energy efficiency of each battery cooling method based on at least one of an air conditioning request (e.g., a required heating index), available power, outside air temperature, battery temperature, powertrain temperature, amount of powertrain waste heat, temperature of each refrigerant, and pressure of each refrigerant. The ECU 500 may also determine the energy efficiency of each heating method based on at least one of a battery temperature control request (e.g., a required cooling index), available power, outside air temperature, battery temperature, powertrain temperature, amount of powertrain waste heat, temperature of each refrigerant, and pressure of each refrigerant.

[0070] 1 and 2, if the first condition is not met (NO in S21), ECU 500 determines in S22 whether a predetermined second condition is met. Specific examples of the second condition will be described later. The second condition is a condition related to the vehicle status and corresponds to the permission condition for heat exchange in S32. If the second condition is met (YES in S22), ECU 500 executes two-fluid heat exchange between the first and second flow paths in S32.

[0071] FIG. 6 is a diagram illustrating the state of the thermal management system when two-fluid heat exchange is performed between the first and second flow paths. As shown in FIG. 6, in S32 of FIG. 4, the ECU 500 stops the third pump 31, activates the first pump 11 and the second pump 21, and controls the metering valve 25 so that the second refrigerant C2 flows through the second section 20b (including the heat exchanger 50). For example, the ECU 500 fully opens the metering valve 25 to set the bypass amount to 0 (no bypass). This allows mutual heat exchange between the first flow path 10 (first refrigerant C1) and the second flow path 20 (second refrigerant C2) in the heat exchanger 50. This two-fluid heat exchange allows the radiator 26 (second refrigerant C2) to cool the battery 12 as well as the vehicle's drive system (the inverter 23 and the motor 24). During the two-fluid heat exchange between the first and second flow paths, the battery 12 can also be heated by an on-board heat source (for example, at least one of waste heat from the powertrain, waste heat from the refrigeration cycle of the air conditioner, and an electric heater).

[0072] The second condition (S22 in FIG. 4) according to this embodiment is met when "battery heating request is present." Furthermore, when "battery cooling request is present," the second condition is met if two-fluid heat exchange between the first and second flow paths (see FIG. 6) is the most efficient battery cooling method compared to other methods (e.g., the battery cooling method using three-fluid heat exchange described above and the battery cooling method using two-fluid heat exchange between the first and third flow paths described below). However, the second condition is not met if there is another battery cooling method that is more efficient than two-fluid heat exchange between the first and second flow paths. Furthermore, the second condition is not met when neither "battery cooling request is present" nor "battery heating request is present" is met.

[0073] 1 and 2, if the second condition is not met (NO in S22), ECU 500 determines in S23 whether a predetermined third condition is met. Specific examples of the third condition will be described later. The third condition is a condition related to the vehicle status, and corresponds to the permission condition for heat exchange in S33. If the third condition is met (YES in S23), ECU 500 executes two-fluid heat exchange between the first and third flow paths in S33.

[0074] FIG. 7 is a diagram illustrating the state of the thermal management system when two-fluid heat exchange between the first and third flow paths is performed. As shown in FIG. 7, in S33 of FIG. 4, the ECU 500 activates all of the first pump 11, the second pump 21, and the third pump 31 and controls the metering valve 25 so that the second refrigerant C2 does not flow into the second section 20b (the heat exchanger 50 side). The ECU 500, for example, fully closes the metering valve 25 to set the non-bypass amount to zero (no flow into the heat exchanger 50). This allows mutual heat exchange between the first flow path 10 (the first refrigerant C1) and the third flow path 30 (the third refrigerant C3) in the heat exchanger 50. This two-fluid heat exchange allows the battery 12 to be cooled by the refrigeration cycle (the third refrigerant C3) of the air conditioner. During the two-fluid heat exchange between the first and third flow paths, the heat pump system of the air conditioner can heat the vehicle interior. The heat pump system can, for example, use waste heat from the battery to heat the vehicle interior. As shown in FIG. 7, the second refrigerant C2 flows through the first portion 20a of the second fluid circuit, and the drive device (inverter 23 and motor 24) of the vehicle is cooled by the radiator 26 (second refrigerant C2).

[0075] The third condition (S23 in FIG. 4 ) according to this embodiment may be satisfied when either “battery cooling request exists” or “heating request exists” is satisfied. When “battery cooling request exists” is satisfied, the third condition is satisfied if two-fluid heat exchange between the first and third flow paths (see FIG. 7 ) is the most efficient battery cooling method compared to other methods (e.g., the battery cooling method using three-fluid heat exchange described above and the battery cooling method using two-fluid heat exchange between the first and second flow paths described above). However, the third condition is not satisfied if there is another battery cooling method that is more efficient than two-fluid heat exchange between the first and third flow paths. Also, when “heating request exists” is satisfied, the third condition is satisfied if two-fluid heat exchange between the first and third flow paths (see FIG. 7 ) is the most efficient heating method compared to other methods (e.g., the heating method using three-fluid heat exchange described above and the heating method using two-fluid heat exchange between the second and third flow paths described below). However, the third condition is not satisfied if there is another heating method that is more efficient than two-fluid heat exchange between the first and third flow paths. Furthermore, if neither "battery cooling request present" nor "heating request present" is satisfied, the third condition is not met.

[0076] 1 and 2, if the third condition is not met (NO in S23), ECU 500 determines in S24 whether a predetermined fourth condition is met. Specific examples of the fourth condition will be described later. The fourth condition is a condition related to the vehicle status, and corresponds to the permission condition for heat exchange in S34. If the fourth condition is met (YES in S24), ECU 500 performs two-fluid heat exchange between the second and third flow paths in S34.

[0077] FIG. 8 is a diagram illustrating the state of the thermal management system when two-fluid heat exchange is performed between the second and third flow paths. As shown in FIG. 8, in S34 of FIG. 4, the ECU 500 stops the first pump 11, activates the second pump 21 and the third pump 31, and controls the metering valve 25 so that the second refrigerant C2 flows through the second section 20b (including the heat exchanger 50). For example, the ECU 500 fully opens the metering valve 25 to set the bypass amount to 0 (no bypass). This allows heat exchange between the second flow path 20 (the second refrigerant C2) and the third flow path 30 (the third refrigerant C3) in the heat exchanger 50. This two-fluid heat exchange allows the vehicle's drive system (the inverter 23 and the motor 24) to be cooled by at least one of the refrigeration cycle (the third refrigerant C3) of the air conditioner and the radiator 26 (the second refrigerant C2). During the two-fluid heat exchange between the second and third flow paths, the heat pump system of the air conditioner can heat the vehicle interior by utilizing at least one of the heat absorbed from the outside air and the waste heat of the powertrain.

[0078] The fourth condition (S24 in FIG. 4) according to this embodiment can be met when "heating required" is satisfied. When "heating required" is satisfied, the fourth condition is met if two-fluid heat exchange between the second and third flow paths (see FIG. 8) is the most efficient heating method compared to other methods (for example, the heating method using three-fluid heat exchange described above and the heating method using two-fluid heat exchange between the first and third flow paths described above). However, the fourth condition is not met if there is another heating method that is more efficient than two-fluid heat exchange between the second and third flow paths. Furthermore, when "heating required" is not satisfied, the fourth condition is not met.

[0079] Referring again to FIG. 4 along with FIGS. 1 and 2, if the fourth condition is not met (NO in S24), the ECU 500 executes individual flow control in S35. When refrigerant flow is required for a purpose other than battery temperature control and air conditioning, the ECU 500 executes the required refrigerant flow by pump control. For example, in a situation where cooling of the vehicle's drive system is required (such as while the vehicle is running), the ECU 500 fully closes the metering valve 25 (no flow into the heat exchanger 50) and activates the second pump 21. The ECU 500 may also execute refrigerant flow for the purpose of temperature equalization. When refrigerant flow is not required, the ECU 500 stops all of the first pump 11, the second pump 21, and the third pump 31.

[0080] When any of the processes in S31 to S35 is executed, the process returns to the first step (S30). The ECU 500 repeatedly executes the series of processes shown in Fig. 4, thereby switching the thermal management mode (S31, S32, S33, S34, S35) depending on the vehicle situation. This makes it possible to execute appropriate thermal management depending on the vehicle situation.

[0081] As described above, the thermal management method according to this embodiment includes the processes shown in FIGS. 3 and 4. In this embodiment, the ECU 500 corresponds to an example of a "computer device" according to the present disclosure. Each process is performed by one or more processors executing a program stored in one or more memories. However, these processes may also be performed by dedicated hardware (electronic circuits) rather than software.

[0082] The thermal management method according to this embodiment includes the steps of: when a first condition relating to the vehicle status is met, operating all of first pump 11, second pump 21, and third pump 31, and controlling metering valve 25 so that second refrigerant C2 flows into second portion 20b (see S31 in FIG. 4 and FIG. 5); and when the first condition is not met and a second condition relating to the vehicle status is met, stopping third pump 31, operating first pump 11 and second pump 21, and controlling metering valve 25 so that second refrigerant C2 flows into second portion 20b (see S32 in FIG. 4 and FIG. 6); When the first condition is not met and a third condition related to the vehicle status is met, the first pump 11, the second pump 21, and the third pump 31 are all put into operation and the metering valve 25 is controlled so that the second refrigerant C2 does not flow into the second portion 20b (see S33 in Figure 4 and Figure 7); and when the first condition is not met and a fourth condition related to the vehicle status is met, the first pump 11 is stopped and the second pump 21 and the third pump 31 are each put into operation and the metering valve 25 is controlled so that the second refrigerant C2 flows into the second portion 20b (see S34 in Figure 4 and Figure 8).

[0083] According to the above method, it is possible to change the manner of heat exchange in the heat exchanger 50 depending on the vehicle conditions, which makes it easier to perform heat management appropriate for the vehicle conditions.

[0084] FIG. 9 is a diagram showing an example of the configuration of a vehicle in which the above-described thermal management system (see FIGS. 1 and 2) is implemented. Referring to FIG. 9 together with FIGS. 1 and 2, the vehicle 1 includes an ECU 500, a battery ECU 600, a first pump 11, a battery 12, a temperature sensor 13, an inlet 110, a charger 120, a charging relay 130, an SMR (System Main Relay) 140, a second pump 21, a temperature sensor 22, an inverter 23, a motor 24, a metering valve 25, a radiator 26, an air conditioner 300, a third pump 31, an outside air temperature sensor 510, an HMI (Human Machine Interface) 520, and a heat exchanger 50. The ECU 500 and the battery ECU 600 are configured to be able to communicate with each other. These ECUs are connected to each other via, for example, a CAN (Controller Area Network). An auxiliary battery (not shown) supplies power to the auxiliary devices (including the ECUs) mounted on the vehicle 1. When the remaining charge in the auxiliary battery becomes low, power is supplied from the battery 12 to the auxiliary battery.

[0085] The vehicle 1 is configured to be able to run using power from a battery 12. The vehicle 1 is, for example, a BEV that does not have an internal combustion engine. A known vehicle power storage device (for example, a liquid secondary battery or an all-solid-state secondary battery) can be used as the battery 12. Examples of vehicle secondary batteries include lithium-ion batteries and nickel-metal hydride batteries.

[0086] The battery 12 is provided with a BMS (Battery Management System) 610, a heater 620, and a blower 630. The BMS 610 includes sensors for detecting the state of the battery 12 (for example, temperature, current, and voltage). The detection result by the BMS 610 is output to the battery ECU 600. The temperature detected by the temperature sensor 13 is also output to the battery ECU 600. The battery ECU 600 transmits the state of the battery 12 and the detected value (temperature T1) of the temperature sensor 13 to the ECU 500, and controls the first pump 11, the charger 120, the charging relay 130, the SMR 140, the heater 620, and the blower 630 according to instructions from the ECU 500. The ECU 500 operates the heater 620 when rapid heating of the battery 12 is required, and operates the blower 630 when rapid cooling of the battery 12 is required. However, in a normal state (a state in which neither rapid heating nor rapid cooling is required), the ECU 500 adjusts the temperature of the battery 12 by the heat exchange described above (see FIGS. 3 and 4).

[0087] In the example shown in FIG. 9, the heat source (object to be cooled) in the first flow path 10 includes the battery 12, an inlet 110, a charger 120, a charging relay 130, and an SMR 140. These heat sources are arranged near the first fluid circuit (first flow path 10) so as to be cooled by the first refrigerant C1. The heat source (object to be cooled) and the first flow path 10 (piping) may be in contact with each other. The inlet 110 is configured to allow a plug (e.g., a connector of a charging cable) for external charging (charging of the battery 12 with power from outside the vehicle) to be detachably attached. The charger 120 includes a power conversion circuit for external charging. The charging relay 130 switches between connecting and disconnecting a charging line. When the charging relay 130 is in a disconnected state, external charging is prohibited. The SMR 140 switches between connecting and disconnecting a basic line of the battery 12. When the SMR 140 is in a disconnected state, use (charging and discharging) of the battery 12 is prohibited.

[0088] The inverter 23 functions as a PCU (Power Control Unit) for the motor 24. The PCU corresponds to a drive circuit for the motor 24. The inverter 23 drives the motor 24 using power supplied from the battery 12. The inverter 23 is controlled by the ECU 500. The motor 24 functions as an MG (Motor Generator). The motor 24 is driven by the inverter 23 to rotate the drive wheels of the vehicle 1. The motor 24 also performs regenerative power generation and outputs the generated power to the battery 12.

[0089] The air conditioner 300 is configured to condition the interior of the vehicle (the interior of the vehicle 1) using a refrigeration cycle. The air conditioner 300 includes a heat pump system 310, a condenser 32, a compressor 321, an expansion valve 322, an evaporator 323, and an interior temperature sensor 330. The interior temperature (temperature inside the vehicle cabin) detected by the interior temperature sensor 330 is output to the ECU 500. The outside temperature (temperature of the outside air around the vehicle) detected by the outside temperature sensor 510 is also output to the ECU 500. The air conditioner 300 is controlled by the ECU 500. A user can set a target air conditioning temperature for the air conditioner 300 through the HMI 520. The HMI 520 includes an input device and a display device. The HMI 520 may include a touch panel display. The HMI 520 may include a smart speaker that accepts voice input. For example, ECU 500 controls air conditioner 300 based on the vehicle interior temperature, the outside temperature, and the target air conditioning temperature so as to bring the vehicle interior temperature closer to the target air conditioning temperature.

[0090] In the vehicle 1 shown in FIG. 9, the first flow path 10, the second flow path 20, and the third flow path 30 are formed independently of one another. A heat exchanger 50 is connected to each of the first flow path 10, the second flow path 20, and the third flow path 30 (see FIGS. 1 and 2). The heat exchanger 50 is configured to exchange heat among the first refrigerant C1 flowing through the first fluid circuit (first flow path 10), the second refrigerant C2 flowing through the second fluid circuit (second flow path 20), and the third refrigerant C3 flowing through the third fluid circuit (third flow path 30). With this configuration, the heat exchanger 50 exchanges heat among the first to third refrigerants, and therefore the third refrigerant C3 cooled by the refrigeration cycle of the air conditioning system 300 can be used to cool the power storage device (battery 12) and the drive device (inverter 23, motor 24). Furthermore, since the first flow path 10, the second flow path 20, and the third flow path 30 are formed independently of one another, it becomes easier to individually adjust each flow path to an appropriate temperature. This makes it possible to appropriately perform thermal management over a wide range of the vehicle 1 (for example, thermal management of a range including the battery 12, the inverter 23, and the motor 24). Furthermore, since all of the first to third refrigerants flow into the common heat exchanger 50 and heat exchange between the first to third refrigerants is performed by the single heat exchanger 50, the structure of the thermal management system is simplified and costs are reduced.

[0091] In the above embodiment, one three-way valve is used as regulating valve 25, but multiple two-way valves may be used to achieve the same function as regulating valve 25. It is not essential to use different types of refrigerants as the first to third refrigerants. For example, water or an aqueous solution may be used as each of the first refrigerant C1 and the second refrigerant C2, and a refrigerant other than cooling water may be used as the third refrigerant C3.

[0092] The heat source (object to be cooled) and the heat dissipation unit in each of the first to third flow paths can be changed or added as appropriate. For example, at least one of an electric heater and an internal combustion engine may be provided as a heat source (object to be cooled) in the second flow path 20. Furthermore, a heat dissipation device other than a radiator may be provided in the second flow path 20.

[0093] The processing flows shown in Figures 3 and 4 can be modified as needed. For example, the order of processing may be changed or unnecessary steps may be omitted depending on the purpose. Furthermore, the content of any of the processing may be changed.

[0094] The configuration of the vehicle is not limited to the configuration described above (FIG. 9). The vehicle may be an xEV (electric vehicle) other than a BEV. The vehicle may be equipped with an internal combustion engine (for example, a gasoline engine, a biofuel engine, or a hydrogen engine). The vehicle is not limited to a four-wheeled passenger car, but may be a bus or truck, or an xEV with three or five or more wheels. The vehicle may be equipped with solar panels. The vehicle may be configured to be capable of contactless charging. The vehicle may be configured to be capable of autonomous driving or may have a flight function. The vehicle may be an unmanned vehicle (for example, a robotaxi, an automated guided vehicle, or agricultural machinery).

[0095] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the description of the above embodiments, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0096] 1 vehicle, 10 first flow path, 11 first pump, 12 battery, 13 temperature sensor, 20 second flow path, 20a first part, 20b second part, 20c third part, 21 second pump, 22 temperature sensor, 23 inverter, 24 motor, 25 metering valve, 26 radiator, 30 third flow path, 31 third pump, 32 condenser, 50 heat exchanger, 300 air conditioning device, 310 heat pump system, 321 compressor, 322 expansion valve, 323 evaporator, 330 interior temperature sensor, 500 ECU, 501 processor, 502 storage device, C1 first refrigerant, C2 second refrigerant, C3 third refrigerant, P1 first end, P2 second end.

Claims

1. a first flow path through which a first refrigerant flows so as to cool an electric storage device mounted on a vehicle; a second flow path through which a second refrigerant flows so as to cool a drive device that drives the vehicle; a third flow path through which a third refrigerant cooled by a refrigeration cycle flows; a heat exchanger connected to each of the first flow path, the second flow path, and the third flow path; a first pump that circulates the first refrigerant through a first fluid circuit formed by the first flow path; a second pump that circulates the second refrigerant through a second fluid circuit formed by the second flow path; a third pump that circulates the third refrigerant through a third fluid circuit formed by the third flow path; A thermal management system comprising: the first flow path, the second flow path, and the third flow path are formed independently of each other, the heat exchanger is configured to mutually exchange heat among the first refrigerant, the second refrigerant, and the third refrigerant, the second flow path includes a first portion passing through the drive device, a second portion connecting from a first end of the first portion to a second end of the first portion through the heat exchanger, and a third portion connecting from the first end of the first portion to the second end of the first portion without passing through the heat exchanger, The thermal management system further includes a metering valve configured to adjust a ratio between an amount of the second refrigerant flowing to the second portion and an amount of the second refrigerant flowing to the third portion, The thermal management system includes: When a first condition related to the state of the vehicle is satisfied, operating all of the first pump, the second pump, and the third pump, and controlling the metering valve so that the second refrigerant flows into the second portion; When the first condition is not satisfied and a second condition related to the vehicle state is satisfied, stopping the third pump, operating the first pump and the second pump, and controlling the metering valve so that the second refrigerant flows into the second portion; When the first condition is not satisfied and a third condition related to the state of the vehicle is satisfied, operating all of the first pump, the second pump, and the third pump, and controlling the metering valve so that the second refrigerant does not flow into the second portion; When the first condition is not satisfied and a fourth condition related to the state of the vehicle is satisfied, stopping the first pump, operating each of the second pump and the third pump, and controlling the metering valve so that the second refrigerant flows into the second portion; A thermal management system that

2. a first flow path through which a first refrigerant flows so as to cool an electric storage device mounted on a vehicle; a second flow path through which a second refrigerant flows so as to cool a drive device that drives the vehicle; a third flow path through which a third refrigerant cooled by a refrigeration cycle flows; a heat exchanger connected to each of the first flow path, the second flow path, and the third flow path; a first pump that circulates the first refrigerant through a first fluid circuit formed by the first flow path; a second pump that circulates the second refrigerant through a second fluid circuit formed by the second flow path; a third pump that circulates the third refrigerant through a third fluid circuit formed by the third flow path; A thermal management system comprising: the first flow path, the second flow path, and the third flow path are formed independently of each other, the heat exchanger is configured to mutually exchange heat among the first refrigerant, the second refrigerant, and the third refrigerant, the second flow path includes a first portion passing through the drive device, a second portion connecting from a first end of the first portion to a second end of the first portion through the heat exchanger, and a third portion connecting from the first end of the first portion to the second end of the first portion without passing through the heat exchanger, The thermal management system further includes a metering valve configured to adjust a ratio between an amount of the second refrigerant flowing to the second portion and an amount of the second refrigerant flowing to the third portion, The thermal management system includes: obtaining a temperature of the first refrigerant flowing into the heat exchanger; obtaining a temperature of the second refrigerant flowing into the heat exchanger; obtaining a required cooling index indicating a required degree of cooling of the power storage device; determining a target value of a flow rate of the second refrigerant to flow through the second portion using the temperature of the first refrigerant, the temperature of the second refrigerant, and the required cooling index; controlling the metering valve so that the amount of the second refrigerant flowing into the second portion approaches the determined target value; A thermal management system that

3. The thermal management system comprises: an air conditioning device that conditions the interior of the vehicle using the refrigeration cycle; Furthermore, the first refrigerant is insulating oil, the second refrigerant is water or an aqueous solution; The thermal management system according to claim 1 or 2, wherein the third refrigerant is an air conditioning refrigerant.

4. The thermal management system according to claim 1 or 2, wherein the metering valve is a three-way valve connected to each of the first portion, the second portion, and the third portion.

5. a first temperature sensor in the first fluid circuit that detects a temperature of the first refrigerant pumped by the first pump after passing through the heat exchanger and the power storage device; a second temperature sensor in the second fluid circuit that detects a temperature of the second refrigerant pumped by the second pump before the second refrigerant passes through the drive device; a control device that controls the metering valve using the detected values ​​of the first temperature sensor and the second temperature sensor; The thermal management system of claim 1 or 2, further comprising:

6. A method for managing the heat of a vehicle using a thermal management system, comprising: The thermal management system includes: a first flow path through which a first refrigerant flows so as to cool an electric storage device mounted on a vehicle; a second flow path through which a second refrigerant flows so as to cool a drive device that drives the vehicle; a third flow path through which a third refrigerant cooled by a refrigeration cycle flows; a heat exchanger connected to each of the first flow path, the second flow path, and the third flow path; a first pump that circulates the first refrigerant through a first fluid circuit formed by the first flow path; a second pump that circulates the second refrigerant through a second fluid circuit formed by the second flow path; a third pump that circulates the third refrigerant through a third fluid circuit formed by the third flow path; Equipped with the first flow path, the second flow path, and the third flow path are formed independently of each other, the heat exchanger is configured to mutually exchange heat among the first refrigerant, the second refrigerant, and the third refrigerant, the second flow path includes a first portion passing through the drive device, a second portion connecting from a first end of the first portion to a second end of the first portion through the heat exchanger, and a third portion connecting from the first end of the first portion to the second end of the first portion without passing through the heat exchanger, The thermal management system further includes a metering valve configured to adjust a ratio between an amount of the second refrigerant flowing to the second portion and an amount of the second refrigerant flowing to the third portion, The method comprises: When a first condition related to the state of the vehicle is satisfied, operating all of the first pump, the second pump, and the third pump, and controlling the metering valve so that the second refrigerant flows into the second portion; When the first condition is not satisfied and a second condition related to the vehicle state is satisfied, stopping the third pump, operating the first pump and the second pump, and controlling the metering valve so that the second refrigerant flows into the second portion; When the first condition is not satisfied and a third condition related to the state of the vehicle is satisfied, operating all of the first pump, the second pump, and the third pump, and controlling the metering valve so that the second refrigerant does not flow into the second portion; When the first condition is not satisfied and a fourth condition related to the state of the vehicle is satisfied, stopping the first pump, operating each of the second pump and the third pump, and controlling the metering valve so that the second refrigerant flows into the second portion; a thermal management method comprising:

7. A method of managing thermal performance of a vehicle using a thermal management system, comprising: The thermal management system includes: a first flow path through which a first refrigerant flows so as to cool an electric storage device mounted on a vehicle; a second flow path through which a second refrigerant flows so as to cool a drive device that drives the vehicle; a third flow path through which a third refrigerant cooled by a refrigeration cycle flows; a heat exchanger connected to each of the first flow path, the second flow path, and the third flow path; a first pump that circulates the first refrigerant through a first fluid circuit formed by the first flow path; a second pump that circulates the second refrigerant through a second fluid circuit formed by the second flow path; a third pump that circulates the third refrigerant through a third fluid circuit formed by the third flow path; Equipped with the first flow path, the second flow path, and the third flow path are formed independently of each other, the heat exchanger is configured to mutually exchange heat among the first refrigerant, the second refrigerant, and the third refrigerant, the second flow path includes a first portion passing through the drive device, a second portion connecting from a first end of the first portion to a second end of the first portion through the heat exchanger, and a third portion connecting from the first end of the first portion to the second end of the first portion without passing through the heat exchanger, The thermal management system further includes a metering valve configured to adjust a ratio between an amount of the second refrigerant flowing to the second portion and an amount of the second refrigerant flowing to the third portion, The method comprises: obtaining a temperature of the first refrigerant flowing into the heat exchanger; obtaining a temperature of the second refrigerant flowing into the heat exchanger; obtaining a required cooling index indicating a required degree of cooling of the power storage device; determining a target value of a flow rate of the second refrigerant to flow through the second portion using the temperature of the first refrigerant, the temperature of the second refrigerant, and the required cooling index; controlling the metering valve so that the amount of the second refrigerant flowing into the second portion approaches the determined target value; a thermal management method comprising:

8. A computer device comprising: a processor; and a storage device that stores a program that causes the processor to execute the thermal management method according to claim 6 or 7.

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