Temperature Control System

Abstract

To enable appropriate temperature control for each of raising battery temperature and heating.SOLUTION: A temperature control system 1 includes an air-conditioning circuit 10, a battery temperature control circuit 20, a heat exchanger 30, a thermometer 42, and a control unit 40. The air-conditioning circuit 10 includes: a heating unit (a heater 14) that heats an air-conditioning heat medium; and an air-conditioning flow rate adjustment unit (a water pump 12) that adjusts a flow rate of the air-conditioning heat medium. The battery temperature control circuit 20 includes a battery flow rate adjustment unit (a water pump 22) that adjusts a flow rate of a battery heat medium. The control unit 40 performs variable control of the flow rate of at least one of the air-conditioning heat medium and the battery heat medium depending on a request for rising battery temperature, a request for indoor heating, and a battery temperature.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a temperature control system that provides both battery heating and room heating. [Background technology]

[0002] Patent Document 1 shows a thermal management system for a vehicle, which includes a refrigerant circuit in which a refrigerant that adjusts the temperature in the vehicle cabin circulates, a heating circuit in which a liquid that exchanges heat with the refrigerant circulates to adjust the temperature in the vehicle cabin, and a battery temperature adjustment circuit that adjusts the temperature of a high-voltage battery by introducing the liquid that exchanges heat with the refrigerant into the high-voltage battery. The heating circuit has a high-voltage heater and can heat the circulating liquid.

[0003] Therefore, the high voltage heater can heat the vehicle interior and increase the temperature of the high voltage battery. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-55342 A Summary of the Invention [Problem to be solved by the invention]

[0005] Patent Document 1 shows that heating is performed using a liquid heated by a high-voltage heater and that this is introduced into a battery temperature control circuit to raise the temperature of a high-voltage battery. Here, when the heat of the high-voltage heater is used for both raising the temperature of the battery and for heating, it is required to appropriately distribute the heat between the battery and heating depending on the situation, but Patent Document 1 does not take such a point into consideration. [Means for solving the problem]

[0006] The present invention includes an air conditioning circuit that circulates an air-conditioning heat medium and adjusts the temperature of a room by heat exchange between the air-conditioning heat medium and indoor air, a battery temperature control circuit that circulates a battery heat medium and adjusts the temperature of a battery by heat exchange between the battery heat medium and a battery, a heat exchanger that exchanges heat between the air-conditioning heat medium and the battery heat medium, a thermometer that detects a battery temperature of the battery, the air conditioning circuit, and a control unit that controls the battery temperature control circuit, wherein the air conditioning circuit includes a heating unit that heats the air-conditioning heat medium and an air-conditioning flow rate adjustment unit that adjusts a flow rate of the air-conditioning heat medium, and the battery temperature control circuit includes a battery flow rate adjustment unit that adjusts the flow rate of the battery heat medium, and the control unit variably controls the flow rate of at least one of the air-conditioning heat medium and the battery heat medium in accordance with a battery temperature increase request, a room heating request, and the battery temperature.

[0007] The control unit may variably control a flow rate of the battery heat medium in response to the temperature increase request, the heating request, and the battery temperature.

[0008] The temperature increase request may be a request issued when rapid charging of the battery is performed. Effect of the Invention

[0009] According to the present invention, the flow rate of the battery heat medium can be variably controlled in accordance with the battery temperature increase request, the heating request, and the battery temperature, thereby making it possible to appropriately distribute heat to the battery temperature increase and the heating. [Brief description of the drawings]

[0010] [Figure 1] 1 is a block diagram showing a system configuration of a temperature control system according to an embodiment. [Diagram 2] 4 is a flowchart showing the control of the air conditioning circuit 10 and the battery temperature adjustment circuit 20. [Diagram 3] FIG. 11 is a diagram showing changes over time in the duty ratio of the water pump 22 at high output and at normal output. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiment described herein.

[0012] System Configuration 1 is a block diagram showing a system configuration of a temperature control system according to an embodiment of the present invention, which is intended to be installed in a vehicle.

[0013] The temperature control system 1 includes an air conditioning circuit 10, a battery temperature control circuit 20, and a heat exchanger 30 that exchanges heat between the air conditioning circuit 10 and the battery temperature control circuit 20.

[0014] The air conditioning circuit 10 is a circuit that circulates an air conditioning heat medium, and includes a water pump (WP) 12, a heater 14, and a heater core 16. The air conditioning heat medium discharged by the water pump 12 is heated by the heater 14, passes through the heater core 16, and heats the indoor air by heat exchange with the indoor air in the heater core 16. The heater 14 is referred to as a heating unit.

[0015] The air-conditioning heat medium may be a liquid such as water to which an anti-rust agent has been added, and various liquid pumps may be used as the water pump 12. The heater 14 may be an electric heater that generates heat by receiving power from an on-board battery, and may heat the air-conditioning heat medium flowing through the passage by heat transfer. The heater core 16 is a heat exchanger, and indoor air flows outside the passage through which the air-conditioning heat medium flows, where the temperature of the indoor air is raised by heat exchange. A blower 18 is provided to flow the indoor air through the heater core 16. The water pump 12 is called an air-conditioning flow rate adjustment unit.

[0016] In addition, a branch valve 44 is provided in the flow path from the heater 14 to the heater core 16, allowing a part or all of the air-conditioning heat medium from the heater 14 to bypass the heater core 16 and circulate to the heat exchanger 30.

[0017] The battery temperature adjustment circuit 20 is a circuit that circulates a battery heat medium, and circulates the battery heat medium discharged from a water pump (WP) 22 through the battery 24, where heat exchange increases the temperature of the battery 24. The water pump 22 is referred to as a battery flow rate adjustment unit.

[0018] The heat medium for the battery may be a liquid such as water similar to the heat medium for air conditioning, and the water pump 22 may be similar to the water pump 12 .

[0019] The battery 24 may be, for example, a lithium-ion battery, and a predetermined voltage is obtained by connecting a predetermined number of battery cells in series, and a predetermined battery capacity is ensured by connecting them in parallel. The output of the battery 24 is usually several hundred volts or more, and is used as a power source for a vehicle drive motor, and is also used to charge an auxiliary battery after being stepped down by a DCDC converter or the like. The heater 14 may be supplied with power from the auxiliary battery, but it can also be supplied with power directly from the battery 24. A flow path for a battery heat medium is formed inside the case of the battery 24, and the temperature of the battery 24 is raised by heat exchange therein.

[0020] In the heat exchanger 30, the flow path of the air-conditioning heat medium and the flow path of the battery heat medium are adjacent to each other, so that heat exchange is performed between the two.

[0021] A thermometer 32 is attached to the battery 24 to measure the battery temperature (temperature of the battery cells). The battery temperature measured by the thermometer 32 is supplied to the control unit 40.

[0022] The control unit 40 is supplied with information such as the room temperature, the state of the heating switch (heating request), and a request to charge the battery 24, and controls the operation of the water pumps 12, 22, etc. When there is a request to charge the battery 24 and the battery temperature is low, the control unit 40 raises the temperature of the battery 24 using the battery temperature control circuit 20. When there is a request to heat the battery 24, the control unit 40 heats the room using the air conditioning circuit 10. The battery temperature control circuit 20 uses heat from the heat exchanger 30, i.e., the heat of the heater 14, to raise the temperature of the battery 24. Therefore, when there is a request to raise the temperature of both the battery 24 and heating, the heat from the heater 14 is used by both the air conditioning circuit 10 and the battery temperature control circuit 20. Therefore, the control unit 40 adjusts the distribution of heat from the heater 14.

[0023] Controlling the System FIG. 2 is a flowchart showing the control of the air conditioning circuit 10 and the battery temperature adjustment circuit 20 by the control unit 40.

[0024] First, it is determined whether there is a charging request, particularly a quick charging request (S11). For example, this applies when the vehicle is stopped and the battery 24 is charged with power from an external quick charger. This quick charging may also include cases in which, in a hybrid vehicle, charging is performed using power generated by the engine or regenerative power generated by regenerative braking.

[0025] If the determination in S11 is NO, processing during charging is not necessary, and processing is terminated. If the determination in S11 is YES, it is determined whether the battery temperature is lower than set temperature 1 (S12). Set temperature 1 is a temperature for determining whether or not it is necessary to increase the temperature of the battery 24, and a temperature of about 5-10°C is used, for example. If the battery temperature is not lower than set temperature 1, battery heating is not necessary, and processing is terminated.

[0026] If the determination in S12 is YES, it is determined whether there is a heating request (S13). If the determination in S13 is NO, distribution processing is not necessary and the processing is terminated. As described above, a heating request may be detected by turning on a heating switch in the room. If the determination in S13 is YES, the output of heater 14 is maximized (S14). If there are both a battery temperature increase request and a heating request, the amount of heat required is large, so the amount of heat generated by heater 14 is maximized and then distributed.

[0027] Next, it is determined whether the battery temperature is lower than a set temperature 2 (S15). Set temperature 2 is set to, for example, about 0° C. This is because when the battery temperature falls below about 0° C., the charging characteristics of the battery cells deteriorate significantly, making it increasingly necessary to raise the temperature of the battery 24.

[0028] If the determination in S15 is YES, the output of the water pump 12 in the air conditioning circuit 10 is set to high output, and the branch valve (three-way valve) 44 is controlled to turn on the bypass, that is, to branch the air-conditioning heat medium to the bypass side (S16). The amount of branching may be determined in advance, for example, to a value of about 50%. Also, the amount of branching may be changed according to the battery temperature so that the lower the battery temperature, the greater the amount of branching.

[0029] Furthermore, the output of the water pump 22 of the battery temperature adjustment circuit 20 is set to high output (S17).

[0030] In this way, when the determination in S15 is YES, the output of the heater 14 is set to the maximum to maximize the amount of heating, and the flow rate of the air-conditioning heat medium flowing through the heat exchanger 30 in the air-conditioning circuit 10 is increased, and further the flow rate of the air-conditioning heat medium flowing through the heat exchanger 30 in the battery temperature control circuit 20 is increased. This increases the flow rate of the battery heat medium flowing through the battery 24 and increases its temperature, increasing the amount of heating of the battery 24 and speeding up the temperature rise. On the other hand, the amount of air-conditioning heat medium flowing through the heater core 16 is reduced, which is insufficient for heating, and a battery temperature rise priority process is performed, which prioritizes battery temperature rise.

[0031] If the determination in S15 is NO, the output of the water pump 12 in the air conditioning circuit 10 is set to normal and the bypass is turned off by the branch valve 44, i.e., the air conditioning heat medium is not branched to the bypass side (S18). In addition, the output of the water pump 22 in the battery temperature control circuit 20 is set to high output (S19).

[0032] In this way, when the determination in S15 is NO, the output of the heater 14 is set to the maximum and the flow rate of the air-conditioning heat medium flowing through the heat exchanger 30 in the air-conditioning circuit 10 is increased, but the bypass of the air-conditioning circuit 10 is turned off and the entire amount flows through the heater core 16. Therefore, the amount of air-conditioning heat medium flowing through the heater core 16 is increased and sufficient for heating. The flow rate of the air-conditioning heat medium flowing through the heat exchanger 30 in the battery temperature control circuit 20 is set to normal. As a result, the flow rate of the battery heat medium flowing through the battery 24 becomes normal, the amount of heat received by the heat exchanger 30 is less than when S15 is YES, and the temperature rise of the battery 24 is limited.

[0033] In this way, if the determination in S15 is NO, heating priority processing is performed in which heating is prioritized over increasing the temperature of the battery 24.

[0034] 3 shows the change over time in the duty ratio of the power supplied to the water pump 22 when the water pump 22 is at high output and normal output. As shown, in the case of high output, the rise is quick and the duty ratio is set large, whereas in the case of normal output, the duty ratio is set relatively small. By setting the duty ratio in this way, the flow rate of the water pump 22 can be set. Note that the flow rate of the water pump 12 can also be controlled by the duty ratio in a similar manner.

[0035] In the above embodiment, the target is the temperature rise of the battery 24 during quick charging. However, even when not charging, the capacity of the battery cell decreases when the temperature is low. Therefore, when the battery temperature is low and a request to raise the temperature of the battery 24 and a request to heat the battery overlap, it is advisable to apply the above-mentioned processing.

[0036] If the result of S15 is YES, that is, battery warming is prioritized, the air volume of the blower 18 may be reduced to reduce the amount of heat dissipated by the heater core 16, and the amount of heat used for warming the battery may be increased.

[0037] Also, if S15 is NO, i.e., heating is prioritized, the indoor temperature may be measured, and the air volume of blower 18 may be automatically adjusted according to the difference from the target temperature. That is, when the difference from the target temperature is large, the air volume may be increased, so that the room temperature can be brought closer to the target temperature. Furthermore, when the difference from the target temperature is small, the flow rate of water pump 12 may be automatically adjusted according to the difference from the target temperature. That is, when the difference from the target temperature is large, the flow rate is increased. [Explanation of symbols]

[0038] 1: temperature control system, 10: air conditioning circuit, 12: water pump, 14: heater, 16: heater core, 18: blower, 20: battery temperature control circuit, 22: water pump, 24: battery, 30: heat exchanger, 32: thermometer, 40: control unit, 44: branch valve.

Claims

1. an air conditioning circuit that circulates an air conditioning heat medium and adjusts a room temperature by heat exchange between the air conditioning heat medium and indoor air; a battery temperature control circuit that circulates a heat medium for the battery and adjusts the temperature of the battery by heat exchange between the heat medium for the battery and the battery; a heat exchanger that exchanges heat between the air-conditioning heat medium and the battery heat medium; a thermometer for detecting a battery temperature of the battery; a control unit for controlling the air conditioning circuit and the battery temperature control circuit; Including, The air conditioning circuit includes: A heating unit that heats the air-conditioning heat medium; an air conditioning flow rate adjusting unit that adjusts the flow rate of the air conditioning heat medium; Including, The battery temperature control circuit includes: a battery flow rate adjusting unit that adjusts the flow rate of the battery heat medium; Including, The control unit variably controls a flow rate of at least one of the air-conditioning heat medium and the battery heat medium in response to a temperature increase request for the battery, a heating request for the room, and the battery temperature. Temperature control system.

2. 2. The temperature control system of claim 1, The control unit variably controls a flow rate of the battery heat medium in response to the temperature increase request, the heating request, and the battery temperature. Temperature control system.

3. 3. The temperature control system according to claim 1, the temperature increase request is issued when rapid charging of the battery is performed; Temperature control system.

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