Heat medium circulation device for vehicle

Abstract

To provide a heat medium circulation device for a vehicle that can reduce the frequency of cooling or heating a battery.SOLUTION: A heat medium circulation device for a vehicle includes: a battery temperature control circuit in which a heat medium supplied to a battery is circulated; a battery temperature sensor that detects a temperature of the battery; an outside air temperature sensor that detects an outside air temperature; and a controller. The battery temperature control circuit includes a pump that circulates the heat medium and a temperature control device that changes the temperature of the heat medium. The controller has a pump control part that operates the pump based on the temperature of the battery and the outside air temperature when the temperature of the battery is within a predetermined range and the temperature control device is stopped.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a heat medium circulating device for a vehicle including a battery temperature regulating circuit through which a heat medium to be supplied to a battery is circulated. [Background technology]

[0002] Patent Document 1 discloses a vehicle coolant circulation device that includes a battery temperature adjustment cycle for adjusting the temperature of a battery. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-93561 A Summary of the Invention [Problem to be solved by the invention]

[0004] An electric vehicle runs by driving a motor with battery power. The battery generates heat while running. If the battery becomes too hot, it deteriorates, and if the battery becomes too cold, its performance decreases. In order to maintain the battery temperature within a specified range, an electric vehicle controls the battery temperature by regulating the temperature of the heat medium circulating in a battery temperature regulation circuit. For example, when the outside temperature is high, such as in summer, and the battery temperature exceeds an upper limit, the battery is cooled. When the battery temperature returns to within the specified range, the battery cooling is stopped. However, when the outside temperature is high, the battery temperature rises immediately, and the battery needs to be cooled again. Since the battery is cooled frequently, the power consumption for cooling the battery increases. As a result, the range of the electric vehicle is shortened.

[0005] An object of the present invention is to provide a heat medium circulating device for a vehicle that can reduce the frequency of cooling or heating a battery. [Means for solving the problem]

[0006] (1) A heat medium circulating device for a vehicle according to one aspect of the present invention includes a battery temperature regulation circuit through which a heat medium supplied to a battery is circulated, a battery temperature sensor that detects the temperature of the battery, an outside air temperature sensor that detects the outside air temperature, and a controller. The battery temperature regulation circuit has a pump that circulates the heat medium, and a temperature regulation device that changes the temperature of the heat medium. The controller has a pump control unit that operates the pump based on the temperature of the battery and the outside air temperature when the temperature of the battery is within a predetermined range and the temperature regulation device is stopped.

[0007] (2) The heat medium circulating device for a vehicle described in (1) above may include a vehicle speed sensor that detects the vehicle speed of the vehicle and a solar radiation sensor that detects the amount of solar radiation. The pump control unit may operate the pump when the outside air temperature is equal to or higher than a predetermined threshold and at least one of a first condition and a second condition is satisfied. The first condition is that the temperature of the battery is higher than the outside air temperature, and the second condition is that the vehicle speed is equal to or lower than a predetermined threshold and the amount of solar radiation is equal to or higher than a predetermined threshold. Effect of the Invention

[0008] The heat medium circulating device for a vehicle described above in (1) operates a pump in a battery temperature adjustment circuit when the battery is not being cooled or heated. By circulating the heat medium, the temperature of the heat medium in the entire battery temperature adjustment circuit is made as uniform as possible. This makes it possible to suppress temperature changes in the battery caused by the influence of the outside air temperature. Since the frequency of cooling or heating the battery is reduced, the frequency of use of the temperature adjustment device can be reduced. Therefore, the power consumption of the temperature adjustment device used to cool or heat the battery can be reduced.

[0009] For example, when the outside air temperature is high in summer, even if the battery temperature is within a predetermined range, the temperature rise of the heat medium circulating in the battery temperature regulation circuit can be suppressed by operating only the pump, and the frequency with which the battery needs to be cooled can be reduced.

[0010] The heat medium circulating device for a vehicle described above in (2) can suppress temperature changes in the battery caused by the influence of road surface temperature. When the vehicle is stopped or traveling at a low speed, the battery is susceptible to the influence of road surface temperature, and the temperature of the battery is likely to rise due to radiant heat from the road surface. When the battery is susceptible to the influence of road surface temperature, the pump is operated so that the radiant heat from the road surface is received by the heat medium in the entire battery temperature adjustment circuit. This makes it possible to suppress the temperature rise of the battery caused by the influence of road surface temperature. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic diagram showing a configuration of a heat medium circulating device for a vehicle according to an embodiment. [Diagram 2] FIG. 2 is an enlarged schematic diagram showing a battery temperature adjustment circuit provided in the heat medium circulating device for a vehicle according to the embodiment. [Diagram 3] FIG. 3 is a flowchart showing an outline of a control procedure by the controller in the heat medium circulating device for a vehicle according to the embodiment. [Figure 4] FIG. 4 is a flowchart showing an example of battery temperature control by the temperature control unit of the controller in the heat medium circulating device for a vehicle according to the embodiment. [Diagram 5] FIG. 5 is a flowchart showing an example of the first pump control by the pump control unit of the controller in the heat medium circulating device for a vehicle according to the embodiment. [Figure 6] FIG. 6 is a flowchart showing another example of the first pump control by the pump control unit of the controller in the heat medium circulating device for a vehicle according to the embodiment. [Figure 7] FIG. 7 is a flowchart showing an example of the second pump control by the pump control unit of the controller in the heat medium circulating device for a vehicle according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] A specific example of a heat medium circulating device for a vehicle according to an embodiment of the present invention will be described with reference to the drawings. In each drawing, the same or corresponding parts are given the same reference numerals. The sizes of the members shown in each drawing are expressed for the purpose of clarifying the description, and do not necessarily represent the actual dimensions.

[0013] <Heat medium circulator for vehicles> An electric vehicle 1 including a heat medium circulating device 1A for a vehicle according to an embodiment will be described with reference to Fig. 1. The electric vehicle 1 is equipped with a battery 10. The electric vehicle 1 is an automobile that runs by driving a motor (not shown) with power from the battery 10. In this example, the electric vehicle 1 is a BEV (Battery Electric Vehicle). The electric vehicle 1 may also be, for example, an HEV (Hybrid Electric Vehicle) or an FCEV (Fuel Cell Electric Vehicle).

[0014] As shown in FIG. 1, the heat medium circulating device 1A for a vehicle according to the embodiment includes a battery temperature adjustment circuit 6, a battery temperature sensor 10t, and an outside air temperature sensor 15. The heat medium to be supplied to the battery 10 is circulated in the battery temperature adjustment circuit 6. The heat medium circulating device 1A for a vehicle according to the embodiment further includes an air conditioning unit 2, a heating circuit 3, a heat pump circuit 4, and a circuit switching valve 7. The heating circuit 3 circulates the heat medium to be supplied to the heater core 26 of the air conditioning unit 2. The heating circuit 3 and the battery temperature adjustment circuit 6 are connected by the circuit switching valve 7. In the following description, the heat medium flowing in the heating circuit 3 is referred to as the first heat medium, and the heat medium flowing in the battery temperature adjustment circuit 6 is referred to as the second heat medium. The heat pump circuit 4 circulates the third heat medium. In FIG. 1, the outline arrows indicate the flow directions of the first heat medium, the second heat medium, and the third heat medium. One of the features of the heat medium circulating device 1A for a vehicle according to the embodiment is that it includes a controller 5 that performs specific control. The controller 5 has a pump control section 52 that operates the pump 61 of the battery temperature adjustment circuit 6 when a specific condition is satisfied. The configuration of the heat medium circulating device 1A for a vehicle will be described in detail below.

[0015] (Battery) The battery 10 is a secondary battery used as a power source for driving the motor of the electric vehicle 1. The battery 10 supplies power to the motor and also to various electrical devices mounted on the electric vehicle 1. The battery 10 generates heat by charging and discharging. The battery 10 of this example has a flow path through which the second heat medium of the battery temperature adjustment circuit 6 flows. The temperature of the battery 10 is adjusted by heat exchange between the battery 10 and the second heat medium. The battery 10 of this example is provided with a battery temperature sensor 10t that detects the temperature of the battery 10. The battery 10 is arranged, for example, at the bottom of the electric vehicle 1.

[0016] (Air conditioning unit) The air conditioning unit 2 is a device that conditions the air inside the vehicle cabin. The air conditioning unit 2 is also called an HVAC (Heating, Ventilation and Air Conditioning) unit. The air conditioning unit 2 adjusts the temperature of air taken in from an inlet 2i and sends the temperature-adjusted air from an outlet 2o into the vehicle cabin.

[0017] The air conditioning unit 2 has a heater core 26, an evaporator 27, an air mix door 28, and a blower 29. In the air conditioning unit 2, the evaporator 27, the air mix door 28, and the heater core 26 are arranged in this order from the inlet 2i toward the outlet 2o. The blower 29 draws in air from the inlet 2i and blows the drawn air toward the outlet 2o. The output of the blower 29 is adjusted to adjust the volume of air blown out from the outlet 2o.

[0018] The evaporator 27 is a component that cools air. A third heat medium is supplied to the evaporator 27 from the heat pump circuit 4 described later. The third heat medium supplied to the evaporator 27 expands by the cooling expansion valve 46 and becomes low temperature and low pressure. The cooling expansion valve 46 is, for example, an electric expansion valve. By supplying the low-temperature third heat medium to the evaporator 27, the evaporator 27 becomes low temperature, and the air passing through the evaporator 27 is cooled. The temperature of the third heat medium that has passed through the evaporator 27 increases due to heat exchange with the air. The evaporator 27 is provided with an evaporator temperature sensor 27t. The evaporator temperature sensor 27t may be one that detects the temperature of the air around the evaporator 27, or one that detects the temperature of the third heat medium supplied to the evaporator 27.

[0019] The heater core 26 is a component that heats air. The heater core 26 is disposed downstream of the evaporator 27. The first heat medium of the heating circuit 3 is supplied to the heater core 26. By supplying the high-temperature first heat medium to the heater core 26, the heater core 26 becomes hot, and the air passing through the heater core 26 is heated. The temperature of the first heat medium that has passed through the heater core 26 is reduced by heat exchange with the air.

[0020] The air mix door 28 is a component that adjusts the ratio of air passing through the heater core 26 to air bypassing the heater core 26. The air mix door 28 is disposed between the evaporator 27 and the heater core 26. When the air mix door 28 is open, the air that has passed through the evaporator 27 passes through the heater core 26. When the air mix door 28 is closed, the air that has passed through the evaporator 27 bypasses the heater core 26. When the air mix door 28 is open, the ratio of air passing through the heater core 26 increases. When the air mix door 28 is closed, the ratio of air passing through the heater core 26 decreases. By adjusting the opening degree of the air mix door 28, the air cooled by the evaporator 27 and the air heated by the heater core 26 are mixed, and the temperature of the air blown out from the air outlet 2o is adjusted. The air outlet 2o is provided with an air outlet temperature sensor 25 that detects the temperature of the air blown out from the air outlet 2o.

[0021] (Heating circuit) The heating circuit 3 is used to heat the heater core 26 when the air conditioning is ON. The heating circuit 3 is also used to heat a second heat medium in the battery temperature adjustment circuit 6 described later in order to heat the battery 10. The heating circuit 3 of this example has a pump 31 that circulates a first heat medium and a heater 32 that heats the first heat medium. The first heat medium is a cooling water such as a long-life coolant (LLC). The pump 31 is, for example, an electric water pump. The heater 32 is an electric heater such as a high-voltage heater (HVH: High Voltage Heater). The heating circuit 3 of this example is configured with a flow path such that the first heat medium sent from the pump 31 returns to the pump 31 via the heater 32 and the heater core 26. When the pump 31 is operated, the first heat medium circulates through the heating circuit 3, and the first heat medium is supplied to the heater core 26. The heater core 26 is heated by heating the first heat medium by one or both of the heater 32 and the heat pump circuit 4 described later. When the air conditioning is OFF, that is, when the heater core 26 is not heated, the pump 31 and the heater 32 are stopped, and the heated first heat medium is not supplied to the heater core 26.

[0022] The heating circuit 3 of this example is provided with a first temperature sensor 35a and a second temperature sensor 35b. The first temperature sensor 35a detects the temperature of the first heat medium supplied to the heater core 26. The first temperature sensor 35a is provided in a flow path between the heater 32 and the heater core 26. The second temperature sensor 35b detects the temperature of the first heat medium that has passed through the heater core 26. The second temperature sensor 35b is provided in a flow path between the heater core 26 and the pump 31.

[0023] The heating circuit 3 may be provided with a reserve tank 33. The reserve tank 33 is a tank for temporarily storing the first heat medium that overflows from the heating circuit 3 due to thermal expansion caused by a temperature rise of the first heat medium. The reserve tank 33 also has a function of separating air bubbles generated in the heating circuit 3. The reserve tank 33 separates the first heat medium and air bubbles in the heating circuit 3 and removes the air bubbles in the heating circuit 3, thereby making it possible to keep the pressure in the heating circuit 3 stable. In this example, the reserve tank 33 is connected in series to the heating circuit 3. The reserve tank 33 is disposed in a flow path between the heater core 26 and the pump 31.

[0024] The heating circuit 3 of this example is capable of heating the first heat medium in the heating circuit 3 by the heat pump circuit 4, which will be described later in detail. The heating circuit 3 of this example includes a heat exchanger 34 that performs heat exchange between the first heat medium and a third heat medium flowing through the heat pump circuit 4, which will be described later. The heat exchanger 34 has a first heat exchange section 34a through which the first heat medium flows and a second heat exchange section 34b through which the third heat medium flows. The first heat exchange section 34a and the second heat exchange section 34b are thermally connected to each other, so that heat exchange is performed between the first heat medium and the third heat medium. The heat exchanger 34 is, for example, a water-cooled condenser. The heat exchanger 34 is disposed in a flow path between the pump 31 and the heater 32. As long as the first heat medium can be heated by the heat pump circuit 4 as in this example, the heater 32 is not an essential component.

[0025] The heating circuit 3 of this example is connected to the heat pump circuit 4 by the heat exchanger 34, and the first heat medium in the heating circuit 3 can be heated by the heat exchanger 34. Therefore, the heating circuit 3 of this example can raise the temperature of the heater core 26 only by the heat pump circuit 4, even if the heater 32 is not operating. Furthermore, the heating circuit 3 of this example can also heat the first heat medium by the heat pump circuit 4 and the heater 32. When the heater core 26 cannot be sufficiently raised in temperature only by the heat pump circuit 4, the heater core 26 can be raised in temperature by both the heat pump circuit 4 and the heater 32.

[0026] (Heat pump circuit) The heat pump circuit 4 is used when the first heat medium in the heating circuit 3 is heated by the heat exchanger 34 when the heater core 26 is heated. The heat pump circuit 4 is also used to cool the evaporator 27 when the air conditioning is ON. Furthermore, the heat pump circuit 4 of this example is also used to cool the second heat medium in the battery temperature adjustment circuit 6 described later in order to cool the battery 10. The heat pump circuit 4 of this example has a compressor 41, a condenser 42, a heating expansion valve 44, and a cooling expansion valve 46. The heat pump circuit 4 of this example has a flow path configured so that the third heat medium discharged from the compressor 41 is sent to the condenser 42 via the heat exchanger 34 and the heating expansion valve 44 of the heating circuit 3. The third heat medium has the property of becoming hot when compressed and becoming cold when expanded. The third heat medium is, for example, hydrofluorocarbon (HFC).

[0027] The compressor 41 compresses and discharges the low-pressure third heat medium sent from the accumulator 45. The compressor 41 is, for example, an electric compressor. The third heat medium compressed to a high temperature and high pressure by the compressor 41 is sent to the heat exchanger 34. The heat exchanger 34 is disposed in a flow path between the compressor 41 and the heating expansion valve 44.

[0028] The heat exchanger 34 exchanges heat between the high-temperature third heat medium sent from the compressor 41 and the first heat medium of the heating circuit 3. The high-temperature third heat medium flows through the second heat exchange section 34b, thereby heating the first heat medium in the first heat exchange section 34a. The first heat medium circulating through the heating circuit 3 is heated, thereby raising the temperature of the heater core 26. The temperature of the third heat medium that has passed through the heat exchanger 34 is reduced by heat exchange with the first heat medium.

[0029] The third heat medium discharged from the heat exchanger 34 is sent to the condenser 42 through the heating expansion valve 44. The third heat medium expands by the heating expansion valve 44 and becomes low temperature and low pressure. The heating expansion valve 44 is, for example, an electric expansion valve.

[0030] The condenser 42 is a device that exchanges heat between the third heat medium in the heat pump circuit 4 and outside air. The condenser 42 is disposed outside the vehicle compartment. Outside air is taken in from the front grille 12 by the fan 11. When the outside air hits the condenser 42, heat is exchanged between the third heat medium flowing through the condenser 42 and the outside air.

[0031] The heat pump circuit 4 of this example has a first flow path 4a, a second flow path 4b, and a third flow path 4c. The first flow path 4a is a flow path that sends the third heat medium from the condenser 42 to the evaporator 27. The first flow path 4a is used when cooling the evaporator 27, that is, when the air conditioning is ON. The second flow path 4b is a flow path that sends the third heat medium from the condenser 42 to a chiller 62 of the battery temperature adjustment circuit 6 described later. The second flow path 4b is used when cooling the battery 10. The third flow path 4c is a bypass flow path that returns the third heat medium from the condenser 42 to the compressor 41. The third flow path 4c is used when the evaporator 27 is not cooled and when the battery 10 is not cooled. The flow paths are switched by the switching valve 40. The switching valve 40 is, for example, an electromagnetic valve. When the switching valve 40 is closed, the third heat medium discharged from the condenser 42 flows toward the first flow path 4a and the second flow path 4b. When the switching valve 40 is open, the third heat medium flows through the third flow path 4c.

[0032] When the evaporator 27 is cooled or when the battery 10 is cooled, the switching valve 40 is closed. When the evaporator 27 is cooled, the third heat medium flows through the first flow path 4a. The third heat medium is sent to the evaporator 27 through the first flow path 4a and then returned to the compressor 41. The third heat medium is expanded by the cooling expansion valve 46 before the evaporator 27 and is supplied to the evaporator 27 in a low-temperature, low-pressure state. When the air conditioning is OFF, that is, when the evaporator 27 is not cooled, the cooling expansion valve 46 is closed and the third heat medium does not flow through the first flow path 4a. That is, the low-temperature third heat medium is not supplied to the evaporator 27.

[0033] When cooling the battery 10, the third heat medium flows through the second flow path 4b. The third heat medium is sent to the chiller 62 through the second flow path 4b, and then returned to the compressor 41. The third heat medium is expanded by the chiller expansion valve 49 before the chiller 62, and is supplied to the chiller 62 in a low-temperature, low-pressure state. The chiller 62 will be described later. When not cooling the battery 10, the chiller expansion valve 49 is closed, and the third heat medium does not flow through the second flow path 4b. In other words, the third heat medium is not supplied to the chiller 62.

[0034] When the evaporator 27 and the battery 10 are not cooled, the switching valve 40 is opened and the third heat medium is returned to the compressor 41 through the third flow path 4c. In this case, the third heat medium does not flow through the first flow path 4a and the second flow path 4b.

[0035] The third heat medium returned to the compressor 41 through any one of the first flow path 4a, the second flow path 4b, and the third flow path 4c is recovered in the accumulator 45. The accumulator 45 separates the liquefied third heat medium and supplies only the vaporized third heat medium to the compressor 41.

[0036] The heat pump circuit 4 of this example is provided with a first temperature sensor 47a, a second temperature sensor 47b, a third temperature sensor 47c, a fourth temperature sensor 47d, a fifth temperature sensor 47e, and a pressure sensor 48. The first temperature sensor 47a detects the temperature of the third heat medium sent from the compressor 41 to the heat exchanger 34. The second temperature sensor 47b detects the temperature of the third heat medium discharged from the heat exchanger 34. The third temperature sensor 47c detects the temperature of the third heat medium discharged from the condenser 42. The fourth temperature sensor 47d detects the temperature of the third heat medium passed through the evaporator 27. The fifth temperature sensor 47e detects the temperature of the third heat medium discharged from the chiller 62. The pressure sensor 48 detects the pressure of the third heat medium discharged from the heat exchanger 34. The second temperature sensor 47b and the pressure sensor 48 are disposed in a flow path between the heat exchanger 34 and the heating expansion valve 44.

[0037] (Battery temperature adjustment circuit) The battery temperature adjustment circuit 6 is a circuit that adjusts the temperature of the battery 10 by using a second heat medium in order to maintain the temperature of the battery 10 within a predetermined range. The temperature of the battery 10 is adjusted by heat exchange between the second heat medium and the battery 10. The above-mentioned predetermined range means an operating temperature range in which the battery 10 operates safely and efficiently. The operating temperature range of the battery 10 depends on the battery specifications. The operating temperature range of the battery 10 is, for example, 0°C or higher and 40°C or lower.

[0038] The battery temperature regulation circuit 6 includes a temperature regulation device 6c that changes the temperature of the second heat medium as shown in FIG. 2 in order to regulate the temperature of the battery 10. The second heat medium is cooled, thereby cooling the battery 10. The second heat medium is heated, thereby raising the temperature of the battery 10. As described later, in this example, the cooling of the battery 10 is realized by a chiller 62 provided in the battery temperature regulation circuit 6. Moreover, the heating circuit 3 and the circuit switching valve 7 raise the temperature of the battery 10. That is, in the battery temperature regulation circuit 6, the chiller 62 functions as a part of the temperature regulation device 6c for cooling the second heat medium. Moreover, the heating circuit 3 and the circuit switching valve 7 function as a part of the temperature regulation device 6c for heating the second heat medium.

[0039] The battery temperature adjustment circuit 6 of this example has a pump 61 that circulates the second heat medium and a chiller 62 that cools the second heat medium. The second heat medium is cooling water such as long-life coolant (LLC). In this example, the second heat medium of the battery temperature adjustment circuit 6 and the first heat medium of the heating circuit 3 are the same. In the battery temperature adjustment circuit 6 of this example, a flow path is configured such that the second heat medium sent out from the pump 61 returns to the pump 61 via the battery 10 and the chiller 62. When the pump 61 is operated, the second heat medium circulates through the battery temperature adjustment circuit 6, and the second heat medium flows through the battery 10. The pump 61 is, for example, an electric water pump.

[0040] The battery temperature adjustment circuit 6 of this example cools the battery 10 by cooling the second heat medium with the chiller 62. The chiller 62 is a heat exchanger that cools the second heat medium using the third heat medium of the heat pump circuit 4 in order to cool the battery 10. The chiller 62 has a first heat exchange section 62a through which the second heat medium flows and a second heat exchange section 62b through which the third heat medium flows. The first heat exchange section 62a and the second heat exchange section 62b are thermally connected to each other, so that heat exchange is performed between the second heat medium and the third heat medium. The low-temperature third heat medium expanded by the chiller expansion valve 49 flows through the second heat exchange section 62b, so that the second heat medium in the first heat exchange section 62a is cooled. The second heat medium circulating in the battery temperature adjustment circuit 6 is cooled, so that the battery 10 is cooled. The temperature of the second heat medium cooled by the chiller 62 is lower than the temperature of the battery 10.

[0041] In the battery temperature adjustment circuit 6 of this example, when the battery 10 is cooled, the pump 61 operates and the second heat medium cooled by the chiller 62 circulates. On the other hand, when the battery 10 is not cooled, the pump 61 is stopped and the second heat medium is not circulated. Furthermore, when the battery 10 is not cooled, the third heat medium of the heat pump circuit 4 is not supplied to the chiller 62 as described above, and therefore the chiller 62 is stopped. Therefore, the second heat medium is not cooled.

[0042] In this example, the chiller 62 is disposed downstream of the battery 10 and cools the second heat medium that has passed through the battery 10. The chiller 62 is provided in the battery temperature adjustment circuit 6, midway through the flow path from the battery 10 to the pump 61. The battery 10 is provided in the battery temperature adjustment circuit 6, midway through the flow path from the pump 61 to the chiller 62. In addition, in order to prevent the pressure of the second heat medium from increasing due to thermal expansion, the battery temperature adjustment circuit 6 in this example is configured to send a portion of the second heat medium to the reserve tank 33 when the pressure of the second heat medium that has passed through the battery 10 reaches a predetermined level or higher.

[0043] The battery temperature adjustment circuit 6 of this example is provided with a temperature sensor 65. The temperature sensor 65 detects the temperature of the second heat medium supplied to the battery 10. The temperature sensor 65 is disposed in a flow path between the pump 61 and the battery 10.

[0044] The battery temperature adjustment circuit 6 of this embodiment does not include a battery heater that heats the second heat medium to increase the temperature of the battery 10.

[0045] (Circuit switching valve) The circuit switching valve 7 is a device that switches the connection state between the heating circuit 3 and the battery temperature regulation circuit 6. In this example, the heating circuit 3 and the battery temperature regulation circuit 6 are connected so that the heat medium can move between the heating circuit 3 and the battery temperature regulation circuit 6 by the circuit switching valve 7. The circuit switching valve 7 allows or blocks the movement of the heat medium. The circuit switching valve 7 is, for example, a solenoid valve.

[0046] The configuration of the circuit switching valve 7 will be described in detail with reference to FIG. 2. The circuit switching valve 7 in this example is a four-way valve that can branch a flow path in four directions. A known four-way valve (for example, JP 2013-238310 A and JP 2020-200902 A) can be used as the four-way valve. The circuit switching valve 7 is not limited to a four-way valve, and may be any valve that can branch a flow path in four or more directions.

[0047] The circuit switching valve 7 of this example is disposed between the heating circuit 3 and the battery temperature adjustment circuit 6, and has four connection ports. The circuit switching valve 7 connects the middle of the heating circuit 3 to the middle of the battery temperature adjustment circuit 6. The connection point of the circuit switching valve 7 in the heating circuit 3 is provided in the middle of the flow path from the heater core 26 to the pump 31, more specifically, in the flow path between the second temperature sensor 35b and the reserve tank 33. Of the four connection ports of the circuit switching valve 7, the first connection port and the second connection port are connected to points A and B of the heating circuit 3, respectively. The connection point of the circuit switching valve 7 in the battery temperature adjustment circuit 6 is provided in the middle of the flow path from the chiller 62 to the pump 61. Of the four connection ports of the circuit switching valve 7, the third connection port and the fourth connection port are connected to points C and D of the battery temperature adjustment circuit 6, respectively.

[0048] When the circuit switching valve 7 is closed, the circuit switching valve 7 is shut off. When the circuit switching valve 7 is shut off, the heating circuit 3 and the battery temperature adjustment circuit 6 are parallel circuits independent of each other. When the circuit switching valve 7 is shut off, the first heat medium of the heating circuit 3 is not sent to the battery temperature adjustment circuit 6, and the second heat medium of the battery temperature adjustment circuit 6 is not sent to the heating circuit 3. In other words, the movement of the heat medium between the heating circuit 3 and the battery temperature adjustment circuit 6 is not possible. When the circuit switching valve 7 is shut off, all of the first heat medium that entered the circuit switching valve 7 from point A of the heating circuit 3 flows from the circuit switching valve 7 to point B of the heating circuit 3. Therefore, the first heat medium circulates through the heating circuit 3 without being sent to the battery temperature adjustment circuit 6 through the circuit switching valve 7. Also, when the circuit switching valve 7 is shut off, all of the second heat medium that entered the circuit switching valve 7 from point C of the battery temperature adjustment circuit 6 flows from the circuit switching valve 7 to point D of the battery temperature adjustment circuit 6. Therefore, the second heat medium circulates through the battery temperature adjustment circuit 6 without passing through the circuit switching valve 7 and being sent to the heating circuit 3 .

[0049] When the circuit switching valve 7 is opened, the circuit switching valve 7 is opened. When the circuit switching valve 7 is opened, the heating circuit 3 and the battery temperature adjustment circuit 6 are connected to form a series circuit. When the circuit switching valve 7 is opened, the first heat medium of the heating circuit 3 is sent to the battery temperature adjustment circuit 6, and the second heat medium of the battery temperature adjustment circuit 6 is sent to the heating circuit 3. That is, the heat medium can move between the heating circuit 3 and the battery temperature adjustment circuit 6. When the circuit switching valve 7 is opened, the first heat medium that entered the circuit switching valve 7 from point A of the heating circuit 3 flows from the circuit switching valve 7 to point D of the battery temperature adjustment circuit 6. Therefore, the first heat medium is sent to the battery temperature adjustment circuit 6 through the circuit switching valve 7 and flows through the battery temperature adjustment circuit 6. Also, when the circuit switching valve 7 is opened, the second heat medium that entered the circuit switching valve 7 from point C of the battery temperature adjustment circuit 6 flows from the circuit switching valve 7 to point B of the heating circuit 3. Therefore, the second heat medium is sent to the heating circuit 3 through the circuit switching valve 7 and flows through the heating circuit 3. That is, when the circuit switching valve 7 is in an open state, the first heat medium in the heating circuit 3 and the second heat medium in the battery temperature adjustment circuit 6 are mixed.

[0050] The opening degree of the circuit switching valve 7 in this example is adjustable. By adjusting the opening degree of the circuit switching valve 7, the amount of heat medium moving between the heating circuit 3 and the battery temperature adjustment circuit 6 can be adjusted. Specifically, the circuit switching valve 7 allows a part of the first heat medium that has entered the circuit switching valve 7 from point A of the heating circuit 3 to flow to point D of the battery temperature adjustment circuit 6, and the remaining part of the first heat medium to flow to point B of the heating circuit 3. In addition, the circuit switching valve 7 allows a part of the second heat medium that has entered the circuit switching valve 7 from point C of the battery temperature adjustment circuit 6 to flow to point B of the heating circuit 3, and the remaining part of the second heat medium to flow to point D of the battery temperature adjustment circuit 6. When the circuit switching valve 7 is fully open, the entire first heat medium that has entered the circuit switching valve 7 from the heating circuit 3 is sent to the battery temperature adjustment circuit 6, and the entire second heat medium that has entered the circuit switching valve 7 from the battery temperature adjustment circuit 6 is sent to the heating circuit 3.

[0051] The battery temperature regulation circuit 6 in this example increases the temperature of the battery 10 by sending the first heat medium of the heating circuit 3 to the battery temperature regulation circuit 6 via the circuit switching valve 7. When increasing the temperature of the battery 10, the pump 61 operates and the heater 32 heats the first heat medium of the heating circuit 3. The first heat medium may be heated by the above-mentioned heat pump circuit 4. The heater 32 and the heat pump circuit 4 may be used in combination to heat the first heat medium.

[0052] When the temperature of the battery 10 is increased, the circuit switching valve 7 is switched to an open state. When the circuit switching valve 7 is in an open state, the first heat medium heated in the heating circuit 3 is sent to the battery temperature adjustment circuit 6. In other words, the second heat medium in the battery temperature adjustment circuit 6 can be heated using the heater 32 or the heat pump circuit 4 of the heating circuit 3, or using the heater 32 and the heat pump circuit 4 in combination. The first heat medium and the second heat medium are mixed to heat the second heat medium. The second heat medium circulating in the battery temperature adjustment circuit 6 is heated, thereby increasing the temperature of the battery 10.

[0053] When raising the temperature of the battery 10, it is sufficient that at least one of the pumps 31 of the heating circuit 3 and the pump 61 of the battery temperature adjustment circuit 6 is operating. When the circuit switching valve 7 is in an open state, the heating circuit 3 and the battery temperature adjustment circuit 6 form a series circuit, so that when at least one of the pumps is operating, the first heat medium flows through the heating circuit 3 and the second heat medium flows through the battery temperature adjustment circuit 6.

[0054] When the temperature of the battery 10 is not being increased, the circuit switching valve 7 is switched to the shutoff state. When the circuit switching valve 7 is in the shutoff state, the first heat medium of the heating circuit 3 is not sent to the battery temperature adjustment circuit 6, and therefore the second heat medium of the battery temperature adjustment circuit 6 is not heated by the first heat medium. In addition, when the temperature of the battery 10 is not being increased, the pump 61 is stopped.

[0055] Unlike the battery temperature adjustment circuit 6 of this example shown in FIG. 1, the battery temperature adjustment circuit 6 may include a battery heater (not shown) that heats the second heat medium. The battery heater is used to increase the temperature of the battery 10. The battery heater is an electric heater such as a high-voltage heater. The battery heater heats the second heat medium supplied to the battery 10. The battery heater is provided, for example, in the middle of the flow path from the pump 61 to the battery 10. When the battery 10 is not increased in temperature, the pump 61 and the battery heater are stopped, and the heated second heat medium is not supplied to the battery 10. When the battery temperature adjustment circuit 6 includes a battery heater, the circuit switching valve 7 is not an essential component.

[0056] (Outside air temperature sensor) The outside air temperature sensor 15 detects the air temperature outside the vehicle compartment, that is, the outside air temperature. The outside air temperature sensor 15 is provided, for example, between the front grille 12 and the condenser 42.

[0057] (Other sensors) The heat medium circulating device 1A for a vehicle of this embodiment further includes a vehicle speed sensor 16 and a solar radiation sensor 17. The vehicle speed sensor 16 detects the vehicle speed of the electric vehicle 1. The solar radiation sensor 17 detects the amount of solar radiation.

[0058] In the electric vehicle 1 of this example, the battery 10 and the second heat medium in the battery temperature regulation circuit 6 are affected by the outside air temperature. A part of the battery temperature regulation circuit 6 including the battery 10 is exposed to the outside air. Therefore, heat exchange occurs between the second heat medium in the battery temperature regulation circuit 6 and the outside air. When the outside air temperature is higher than the temperature of the battery 10 and the second heat medium, the battery 10 and the second heat medium receive heat from the outside air, and the temperatures of the battery 10 and the second heat medium are likely to rise. While the electric vehicle 1 is traveling, the battery 10 generates heat due to discharge, and the temperatures of the battery 10 and the second heat medium may rise.

[0059] Furthermore, since the battery 10 is disposed under the electric vehicle 1, the battery 10 and the second heat medium in the battery temperature regulation circuit 6 are easily affected by the road surface temperature. The higher the road surface temperature, the greater the radiant heat from the road surface, and therefore the easier it is for the temperature of the battery 10 and the second heat medium to rise. When the road surface temperature is higher than the outside air temperature, the battery 10 and the second heat medium are more easily affected by the road surface temperature than by the outside air temperature. In particular, when the road surface temperature is 50°C or higher, or even 55°C or higher, the temperature of the battery 10 and the second heat medium is more likely to rise due to the strong influence of the road surface temperature. The road surface temperature is affected by the outside air temperature and the amount of solar radiation, etc. The road surface temperature rises in places exposed to direct sunlight, i.e., in the sun. The higher the outside air temperature and the greater the amount of solar radiation, the easier it is for the road surface temperature to rise. When the amount of solar radiation on the road surface is, for example, 800 W / m 2 Above 1000W / m 2 In the above cases, the increase in road surface temperature becomes large.

[0060] While the electric vehicle 1 is traveling, the wind from traveling hits a part of the battery temperature regulation circuit 6 including the battery 10, so the battery 10 and the second heat medium in the battery temperature regulation circuit 6 are less susceptible to the influence of the road surface temperature. As the traveling speed of the electric vehicle 1 increases, the influence of the road surface temperature decreases. In other words, the lower the traveling speed of the electric vehicle 1, the greater the influence of the road surface temperature. When the vehicle speed is, for example, 20 km / h or less, the battery 10 is more susceptible to the influence of the road surface temperature.

[0061] (Controller) The controller 5 controls the battery temperature adjustment circuit 6. Furthermore, in this example, the controller 5 controls the air conditioning unit 2, the heating circuit 3, the heat pump circuit 4, and the circuit switching valve 7. The controller 5 in this example is responsible for all controls in the vehicle heat medium circulating device 1A, such as control for performing air conditioning and control for adjusting the temperature of the battery 10. The control for performing air conditioning is control for raising the temperature of the heater core 26 and control for cooling the evaporator 27. The control for adjusting the temperature of the battery 10 is control for raising the temperature or cooling the battery 10.

[0062] The controller 5 is configured, for example, by an electronic control unit (ECU). The ECU includes a processor, a memory, a timer, etc. The memory stores a control program to be executed by the processor, and various data, etc. The processor performs various processes such as arithmetic processing and judgment processing required to execute the control program. The controller 5 operates when the processor executes the control program stored in the memory. The above-mentioned multiple processors, which are physically separated, may cooperate with each other to execute the above-mentioned processes.

[0063] The controller 5 has a temperature control unit 51 and a pump control unit 52. The temperature control unit 51 performs control to adjust the temperature of the battery 10 so that the temperature of the battery 10 is maintained within a predetermined range. Hereinafter, the control to adjust the temperature of the battery 10 is referred to as battery temperature control. The pump control unit 52 performs control to operate the pump 61 when a specific condition is satisfied, even if the temperature of the battery 10 is within the predetermined range.

[0064] Temperature Control Unit When the temperature of the battery 10 is outside a predetermined range, the temperature control unit 51 controls the temperature adjustment device 6c so that the temperature of the battery 10 falls within the predetermined range. As described above, the predetermined range is the operating temperature range of the battery 10. The operating temperature range is, for example, 0°C or higher and 40°C or lower. When the temperature of the battery 10 exceeds the upper limit of the operating temperature range, the temperature control unit 51 starts a cooling control to cool the battery 10. The upper limit is, for example, 40°C. Furthermore, when the temperature of the battery 10 is below the lower limit of the operating temperature range, the temperature control unit 51 starts a heating control to heat the battery 10. The lower limit is, for example, 0°C. The temperature of the battery 10 is acquired by the battery temperature sensor 10t.

[0065] In this example, the cooling control of the battery 10 is performed as follows. The second heat medium of the battery temperature adjustment circuit 6 is cooled by the chiller 62, and the pump 61 is operated. As a result, the cooled second heat medium circulates through the battery temperature adjustment circuit 6, thereby cooling the battery 10. The cooling control is continued until the temperature of the battery 10 becomes equal to or lower than the upper limit value. The temperature of the battery 10 when the cooling control is started and the temperature of the battery 10 when the cooling control is ended may be the same or different. The cooling control is continued until the temperature of the battery 10 becomes lower than the upper limit value, and may end when the temperature of the battery 10 becomes lower than the upper limit value. For example, when the temperature of the battery 10 becomes 5°C lower than the upper limit value, that is, 35°C, the cooling control is ended. The ending temperature of the cooling control may be 3°C lower than the upper limit value, or may be 2°C lower. When the cooling control is ended, the cooling of the second heat medium by the chiller 62 is stopped, and the pump 61 is stopped.

[0066] In this example, the temperature rise control of the battery 10 is performed as follows. The circuit switching valve 7 is switched from a shutoff state to an open state. By opening the circuit switching valve 7, the heating circuit 3 and the battery temperature adjustment circuit 6 are connected to form a series circuit. At least one of the heater 32 and the heat pump circuit 4 heats the first heat medium of the heating circuit 3. Then, at least one of the pump 31 of the heating circuit 3 and the pump 61 of the battery temperature adjustment circuit 6 is operated. As a result, the first heat medium heated in the heating circuit 3 is sent to the battery temperature adjustment circuit 6, thereby warming the second heat medium of the battery temperature adjustment circuit 6. The warmed second heat medium circulates through the battery temperature adjustment circuit 6, thereby raising the temperature of the battery 10. The temperature rise control is continued until the temperature of the battery 10 reaches or exceeds a lower limit. The temperature of the battery 10 when the temperature rise control is started and the temperature of the battery 10 when the temperature rise control is ended may be the same or different. The temperature rise control may be continued until the temperature of the battery 10 exceeds the lower limit, and may be terminated when the temperature of the battery 10 exceeds the lower limit. For example, when the temperature of the battery 10 becomes 5°C higher than the lower limit, i.e., 5°C, the temperature rise control is terminated. The end temperature of the temperature rise control may be 3°C higher or 2°C higher than the lower limit. When the temperature rise control is terminated, the circuit switching valve 7 is switched from an open state to a closed state. In addition, heating of the first heat medium by at least one of the heater 32 and the heat pump circuit 4 is stopped, and the pump 61 is stopped.

[0067] <Pump control section> When the temperature of the battery 10 is within a predetermined range and the temperature adjustment device 6c is stopped, the pump control unit 52 operates the pump 61 based on the temperature of the battery 10 and the outside air temperature. "When the temperature adjustment device 6c is stopped" means that the battery temperature control by the temperature control unit 51 described above, that is, the cooling control or the temperature increase control, is not being executed. The pump control unit 52 operates the pump 61, for example, when the outside air temperature is equal to or higher than the high temperature threshold and at least one of the first condition and the second condition is satisfied. The high temperature threshold is a temperature lower than the upper limit of the above-mentioned operating temperature range, for example, 35°C. The first condition is that the temperature of the battery 10 is higher than the outside air temperature. The second condition is that the vehicle speed is equal to or lower than a predetermined threshold and the amount of solar radiation is equal to or higher than a predetermined threshold. For example, even if the temperature of the battery 10 is equal to or lower than the outside air temperature, the pump 61 is operated when the vehicle speed is equal to or lower than a predetermined threshold and the amount of solar radiation is equal to or higher than a predetermined threshold. Alternatively, when the temperature of the battery 10 is higher than the outside air temperature, the vehicle speed is equal to or lower than a predetermined threshold, and the amount of solar radiation is equal to or higher than a predetermined threshold, the pump 61 is operated. A vehicle speed equal to or lower than a predetermined threshold is a speed at which the vehicle is easily affected by the road surface temperature, for example, 20 km / h or lower. An amount of solar radiation equal to or higher than a predetermined threshold is an amount of solar radiation at which the road surface temperature is likely to rise, for example, 800 W / m 2 Above 1000W / m 2 The outside air temperature is acquired by the outside air temperature sensor 15. The vehicle speed is acquired by the vehicle speed sensor 16. The amount of solar radiation is acquired by the solar radiation sensor 17.

[0068] Furthermore, for example, when the outside air temperature is equal to or lower than a low temperature threshold and the temperature of the battery 10 is lower than the outside air temperature, the pump control unit 52 operates the pump 61. The low temperature threshold is a temperature higher than the lower limit of the above-mentioned operating temperature range, for example, 10°C.

[0069] Control Procedure A specific example of the control procedure by the controller 5 will be described below with reference to FIG. 3 to FIG. 7. When the electric vehicle 1 is started, the controller 5 starts the control procedure of FIG. 3. In the following description, a case where the control is started from a stopped state will be described. When the battery temperature control is stopped, the pump 61 is stopped, that is, in an OFF state. Also, the description will be given on the premise that the air conditioning is stopped, that is, the air conditioning is OFF. In FIG. 3 to FIG. 7, "Tb" indicates the temperature of the battery 10. "TLu" and "TLw" indicate the upper and lower limits of the operating temperature range of the battery 10, respectively. "Tout" indicates the outside air temperature. "Th" and "Tw" indicate the high and low temperature thresholds of the outside air temperature, respectively. "VS" and "VSt" indicate the vehicle speed and the vehicle speed threshold, respectively. "SR" and "SRt" indicate the solar radiation and the solar radiation threshold, respectively. The upper limit value TLu is, for example, 40°C. The lower limit value TLw is, for example, 0°C. The high temperature threshold Th is, for example, 35° C. The low temperature threshold Tw is, for example, 10° C. The vehicle speed threshold VSt is, for example, 20 km / h. The solar radiation threshold SRt is, for example, 800 W / m 2 First, an overview of the control procedure will be described with reference to Fig. 3. The control procedure shown in Fig. 3 is repeatedly executed at a preset cycle.

[0070] <Step S01> In step S01, it is determined whether the temperature Tb of the battery 10 is within a predetermined range. Specifically, it is determined whether the temperature Tb of the battery 10 is within the operating temperature range. If the temperature Tb of the battery 10 is within the predetermined range, that is, if the temperature Tb of the battery 10 is equal to or higher than the lower limit TLw and equal to or lower than the upper limit TLu, the process proceeds to step S02. For example, if the temperature Tb of the battery 10 is equal to or higher than 0°C and equal to or lower than 40°C, the process proceeds to step S02. If the temperature Tb of the battery 10 is outside the predetermined range, that is, if the temperature Tb of the battery 10 is lower than the lower limit TLw or higher than the upper limit TLu, the process proceeds to step S10, where the battery temperature control is performed. For example, if the temperature Tb of the battery 10 is lower than 0°C or higher than 40°C, the battery temperature control is performed.

[0071] <Step S02> In step S02, it is determined whether the outside air temperature Tout is equal to or higher than the high temperature threshold Th. If the outside air temperature Tout is equal to or higher than the high temperature threshold Th, the process proceeds to step S20, where the first pump control is performed. For example, if the outside air temperature is equal to or higher than 35°C, the first pump control is performed. The first pump control will be described later. If the outside air temperature Tout is not equal to or higher than the high temperature threshold Th, i.e., if it is less than 35°C, the process proceeds to step S03.

[0072] <Step S03> In step S03, it is determined whether the outside air temperature Tout is equal to or lower than the low temperature threshold Tw. If the outside air temperature Tout is equal to or lower than the low temperature threshold Tw, the process proceeds to step S30, where the second pump control is performed. For example, if the outside air temperature Tout is equal to or lower than 10°C, the second pump control is performed. The second pump control will be described later. If the outside air temperature Tout is not equal to or lower than the low temperature threshold Tw, i.e., if it is above 10°C, the process ends with the pump 61 stopped. In other words, if the outside air temperature Tout is lower than the high temperature threshold Th and higher than the low temperature threshold Tw, i.e., if the outside air temperature Tout is above 10°C and less than 35°C, the process ends. The order of steps S02 and S03 may be reversed.

[0073] Battery temperature control An example of the procedure for battery temperature control will be described with reference to Fig. 4. As described above, the battery temperature control is performed when the temperature Tb of the battery 10 is outside a predetermined range. The battery temperature control is executed by the temperature control unit 51.

[0074] <Step S11-Step S12> Step S11 determines whether the temperature Tb of the battery 10 exceeds the upper limit value TLu. If the temperature Tb of the battery 10 exceeds the upper limit value TLu, the process proceeds to step S12 for performing cooling control. For example, when the temperature Tb of the battery 10 exceeds 40°C, the cooling control of the battery 10 is started. As described above, the cooling control continues until the temperature Tb of the battery 10 becomes equal to or lower than the upper limit value TLu. When the temperature Tb of the battery 10 reaches the end temperature of the cooling control, the cooling control is terminated. For example, when the temperature Tb of the battery 10 becomes a temperature 5°C lower than the upper limit value TLu, that is, 35°C, the cooling control is terminated. Although the illustration of the detailed process is omitted in FIG. 4, the process waits until the process of the cooling control is completed, and when the cooling control is completed, the pump 61 is stopped. After the process of the cooling control is completed, the process returns to step S10 shown in FIG. 3, and the control procedure in FIG. 3 is terminated.

[0075] 〈Step S13〉 In step S11, if the temperature Tb of the battery 10 does not exceed the upper limit value TLu, the process proceeds to step S13 for performing heating control. As shown in FIG. 3, the process proceeds to step S10 for performing battery temperature control when it is determined in step S01 that "Tb < TLw or Tb > TLu". Therefore, when it is determined in step S11 shown in FIG. 4 that "Tb > TLu" is not satisfied, it is naturally the case of "Tb < TLw". That is, the process proceeds to step S13 when the temperature Tb of the battery 10 is lower than the lower limit value TLw. For example, when the temperature Tb of the battery 10 is lower than 0°C, the heating control of the battery 10 is started. As described above, the heating control continues until the temperature Tb of the battery 10 becomes equal to or higher than the lower limit value TLw. When the temperature Tb of the battery 10 reaches the end temperature of the heating control, the heating control is terminated. For example, when the temperature Tb of the battery 10 becomes a temperature 5°C higher than the lower limit value TLw, that is, 5°C, the heating control is terminated. Although the illustration of the detailed process is omitted in FIG. 4, the process waits until the process of the heating control is completed, and when the heating control is completed, the pump 61 is stopped. After the process of the heating control is completed, the process returns to step S10 shown in FIG. 3, and the control procedure in FIG. 3 is terminated.

[0076] 〈First Pump Control〉 An example of the procedure of the first pump control will be described with reference to Fig. 5. The first pump control is performed when the temperature Tb of the battery 10 is within a predetermined range and the outside air temperature Tout is equal to or higher than the high temperature threshold value Th, that is, when the outside air temperature Tout is equal to or higher than 35°C, as shown in Fig. 3. The first pump control is executed by the pump control unit 52.

[0077] <Step S21> In step S21, it is determined whether the temperature Tb of the battery 10 is higher than the outside air temperature Tout. If the temperature Tb of the battery 10 is equal to or lower than the outside air temperature Tout, the process proceeds to step S22. For example, if the outside air temperature Tout is 35° C. and the temperature Tb of the battery 10 is 30° C., the process proceeds to step S22. If the temperature Tb of the battery 10 is higher than the outside air temperature Tout, the process proceeds to step S24. For example, if the outside air temperature Tout is 35° C. and the temperature Tb of the battery 10 is 38° C., the process proceeds to step S24.

[0078] <Step S22> In step S22, it is determined whether the vehicle speed VS is equal to or less than the threshold value VSt. The vehicle speed VS here is the vehicle speed for a certain period of time. The certain period of time is, for example, 10 seconds or more. The certain period of time may be 10 seconds or 1 minute. If the vehicle speed VS is greater than the threshold value VSt, the process ends with the pump 61 stopped. For example, if the vehicle speed VS for 10 seconds is greater than 20 km / h, the process ends. If the vehicle speed VS is equal to or less than the threshold value VSt, the process proceeds to step S23. For example, if the vehicle speed VS for 10 seconds is equal to or less than 20 km / h, the process proceeds to step S23.

[0079] <Step S23> In step S23, it is determined whether the amount of solar radiation SR is equal to or greater than a threshold value SRt. The amount of solar radiation SR here is the amount of solar radiation for a certain period of time. The certain period of time is, for example, 10 seconds or more. The certain period of time may be 10 seconds or 1 minute. If the amount of solar radiation SR is smaller than the threshold value SRt, the pump 61 is stopped and the process ends. For example, if the amount of solar radiation SR for 10 seconds is 800 W / m 2If the solar radiation SR is less than the threshold value SRt, the process ends. If the solar radiation SR is equal to or greater than the threshold value SRt, the process proceeds to step S24. For example, if the solar radiation SR for 10 seconds is 800 W / m 2 In the above cases, the process proceeds to step S24. The order of steps S22 and S23 may be interchanged.

[0080] <Step S24> In step S24, the pump 61 is operated. After the pump 61 is operated, the process ends. When the process of the first pump control ends, the process returns to step S20 shown in FIG. 3, and the control procedure of FIG. 3 ends. As described above, the control procedure of FIG. 3 is repeatedly executed, so that after a certain time has elapsed, the process returns to step S01. When the pump 61 is operated by the first pump control, the pump 61 continues to operate until the temperature Tb of the battery 10 falls outside the predetermined range. When the temperature Tb of the battery 10 falls outside the predetermined range, that is, when the temperature is less than 0° C. or more than 40° C., the above-mentioned battery temperature control is performed. The pump 61 continues to operate until the outside air temperature Tout falls below the high temperature threshold value Th. When the outside air temperature Tout falls below the high temperature threshold value Th, that is, when the temperature Tout falls below 35° C., the pump 61 is stopped.

[0081] In the example of the first pump control shown in Fig. 5, the pump 61 is operated when the temperature Tb of the battery 10 is higher than the outside air temperature Tout, i.e., when the first condition is satisfied. Also, even if the temperature Tb of the battery 10 is equal to or lower than the outside air temperature Tout, the pump 61 is operated when the vehicle speed VS is equal to or lower than the threshold value VSt and the amount of solar radiation SR is equal to or higher than the threshold value SRt, i.e., when the second condition is satisfied. That is, in the example of the first pump control shown in Fig. 5, the pump 61 is operated when one of the above-mentioned first condition and second condition is satisfied. When neither the first condition nor the second condition is satisfied, the pump 61 is stopped.

[0082] Unlike the first pump control shown in FIG. 5, the pump 61 may be operated when both the first condition and the second condition described above are satisfied. In this case, specifically, the procedure of the first pump control is changed as shown in FIG. 6. In the example of the first pump control shown in FIG. 6, in step S21a, if the temperature Tb of the battery 10 is equal to or lower than the outside air temperature Tout, the process ends with the pump 61 stopped. For example, when the outside air temperature Tout is 35° C. and the temperature Tb of the battery 10 is 30° C., the pump 61 is not operated. If the temperature Tb of the battery 10 is higher than the outside air temperature Tout, the process proceeds to step S22. The process after step S22 is the same as that of the first pump control shown in FIG. 5. In the example of the first pump control shown in FIG. 6, the pump 61 is operated when the temperature Tb of the battery 10 is higher than the outside air temperature Tout, the vehicle speed VS is equal to or lower than the threshold value VSt, and the solar radiation amount SR is equal to or higher than the threshold value SRt. If neither the first condition nor the second condition is satisfied, the pump 61 is stopped.

[0083] Second Pump Control An example of the procedure of the second pump control will be described with reference to Fig. 7. The second pump control is performed when the temperature Tb of the battery 10 is within a predetermined range and the outside air temperature Tout is equal to or lower than the low temperature threshold value Tw, that is, when the outside air temperature Tout is equal to or lower than 10°C, as shown in Fig. 3. The second pump control is executed by the pump control unit 52.

[0084] <Step S31> In step S31, it is determined whether the temperature Tb of the battery 10 is lower than the outside air temperature Tout. If the temperature Tb of the battery 10 is lower than the outside air temperature Tout, the process proceeds to step S32. For example, if the outside air temperature Tout is 10° C. and the temperature Tb of the battery 10 is 5° C., the process proceeds to step S32. If the temperature Tb of the battery 10 is equal to or higher than the outside air temperature Tout, the process ends with the pump 61 stopped. For example, if the temperature Tb of the battery 10 is equal to or higher than 10° C., the pump 61 is not operated.

[0085] <Step S32> In step S32, the pump 61 is operated. After the pump 61 is operated, the process is terminated. When the process of the second pump control is terminated, the process returns to step S30 shown in FIG. 3, and the control procedure of FIG. 3 is terminated. As described above, the control procedure of FIG. 3 is repeatedly executed, so that after a certain time has elapsed, the process returns to step S01. When the pump 61 is operated by the second pump control, the operation of the pump 61 is continued until the temperature Tb of the battery 10 falls outside the predetermined range. When the temperature Tb of the battery 10 falls outside the predetermined range, that is, when the temperature is less than 0° C. or exceeds 40° C., the above-mentioned battery temperature control is performed. The operation of the pump 61 is continued until the outside air temperature Tout exceeds the low temperature threshold value Tw. When the outside air temperature Tout exceeds the low temperature threshold value Tw, that is, when the temperature Tout exceeds 10° C., the pump 61 is stopped.

[0086] The present invention is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0087] 1 Electric vehicles 1A Vehicle heat transfer medium circulator 10 Battery, 10t Battery Temperature Sensor 11 fan, 12 front grill, 15 outside air temperature sensor 16 Vehicle speed sensor, 17 Solar radiation sensor 2 Air Conditioning Unit 2i inlet, 2o outlet, 25 outlet temperature sensor 26 heater core, 27 evaporator, 27t evaporator temperature sensor 28 Air mix door, 29 Blower 3 Heating circuit 31 pump, 32 heater, 33 reserve tank 34 heat exchanger, 34a first heat exchange section, 34b second heat exchange section 35a first temperature sensor, 35b second temperature sensor 4 Heat pump circuit 4a first flow path, 4b second flow path, 4c third flow path 40 switching valve, 41 compressor, 42 condenser 44 Heating expansion valve, 45 Accumulator, 46 Cooling expansion valve, 47a first temperature sensor, 47b second temperature sensor 47c third temperature sensor, 47d fourth temperature sensor, 47e fifth temperature sensor 48 Pressure sensor, 49 Chiller expansion valve 5 Controller, 51 Temperature control section, 52 Pump control section 6 Battery temperature adjustment circuit 6c temperature control device 61 Pump 62 chiller, 62a first heat exchange section, 62b second heat exchange section 65 Temperature sensor, 7 Circuit switching valve Tb Battery temperature, TLu Upper limit, TLw Lower limit Tout Outside temperature, Th High temperature threshold, Tw Low temperature threshold VS vehicle speed, VSt threshold SR solar radiation, SRt threshold

Claims

1. a battery temperature adjustment circuit through which a heat medium supplied to the battery is circulated; a battery temperature sensor for detecting a temperature of the battery; An outside air temperature sensor for detecting an outside air temperature; A controller, The battery temperature adjustment circuit includes: A pump that circulates the heat medium; A temperature adjustment device that changes the temperature of the heat medium, The controller includes: a pump control unit that operates the pump based on the temperature of the battery and the outside air temperature when the temperature of the battery is within a predetermined range and the temperature adjustment device is stopped. Heat transfer medium circulation device for vehicles.

2. A vehicle speed sensor for detecting a vehicle speed; A solar radiation sensor for detecting an amount of solar radiation, The pump control unit operates the pump when the outside air temperature is equal to or higher than a predetermined threshold and at least one of a first condition and a second condition is satisfied; the first condition is that the temperature of the battery is higher than the outside air temperature; The heat medium circulating device for a vehicle according to claim 1 , wherein the second condition is that the vehicle speed is equal to or lower than a predetermined threshold and the amount of solar radiation is equal to or higher than a predetermined threshold.

Images