Heating system

Abstract

The invention relates to a heating system. The heating system includes a flow path, a battery, a cooler, an LT radiator, and a five-way valve. The battery can exchange heat with the heat medium in the flow path. The cooler is provided in the flow path. The LT radiator is provided in the flow path and absorbs heat from outside air of the vehicle. The five-way valve is configured to switch a connection state between the flow paths. The connection state comprises a first state, a second state and a third state. When the five-way valve switches the connection state from one of the first state and the second state to the other state during the heating operation, the five-way valve performs an operation of switching the connection state from the one state to the third state and then switching the connection state from the third state to the other state.

Description

Technical Field

[0001] The present disclosure relates to heating systems. Background Art

[0002] Japanese Patent Application Laid-Open No. 2020-165604 discloses an air conditioning device mounted on a vehicle. The air conditioning device includes a heat pump cycle (HPC: Heat Pump Cycle), a high-temperature side heat medium circuit (heating circuit) and a low-temperature side heat medium circuit. The HPC has a cooler and a condenser. The cooler absorbs heat from the low-temperature side heat medium circuit. The condenser transfers the heat of the HPC to the high-temperature side heat medium circuit. The low-temperature side heat medium circuit has a battery, an external air heat exchange device and a three-way valve (switching device). The battery and the external air heat exchange device function as heat absorption devices, respectively. The three-way valve is used to adjust the amount of heat transfer from the low-temperature side heat medium to the HPC. The modes of the air conditioning device include a heating mode and a cooling and heating mode. In the heating mode, the heat absorbed by the external air heat exchange device is transferred to the high-temperature side heat medium circuit via the cooler and the HPC (using the external air as a heating heat source). In the cooling and heating mode, the heat of the battery is transferred to the high-temperature side heat medium circuit via the cooler and the HPC (using the battery as a heating heat source).

[0003] When either the outside air or the battery is used as a heating heat source, the HPC receives heat via the cooling device and transfers heat to the vehicle's heating circuit (heating operation). When the switching device changes the heating heat source during the heating operation, it switches the connection state between the various flow paths of the heat medium. In this case, the temperature at the outlet of the heating air will change significantly, and the air conditioning comfort in the vehicle interior may be reduced. Summary of the invention

[0004] The present disclosure has been made to solve the above-mentioned problems, and an object of the present disclosure is to provide a heating system that suppresses a decrease in air-conditioning comfort in a vehicle interior.

[0005] The heating system disclosed in the present invention is mounted on a vehicle. The heating system includes a first flow path, a second flow path, and a third flow path, a power storage device, a cooling device, a heat absorption device, a heating circuit, a heat pump cycle, and a switching device. A heat medium can flow in the first flow path, the second flow path, and the third flow path. The power storage device can exchange heat with the heat medium of the first flow path. The cooling device is arranged in the second flow path. The heat absorption device is arranged in the third flow path and is configured to absorb heat from the outside air of the vehicle. The heating circuit heats the cabin of the vehicle. The heat pump cycle performs a heating operation in which the heat medium of the second flow path is received via the cooling device and the heat is transferred to the heating circuit. The switching device is configured to switch the connection state between the first flow path, the second flow path, and the third flow path. The connection state includes a first state, a second state, and a third state. In the first state, the first flow path is cut off from the second flow path and the third flow path, and the second flow path is connected to the third flow path. In the second state, the first flow path is connected to the second flow path and is cut off from the third flow path, and the second flow path is cut off from the third flow path. In the third state, the first flow path is connected to the second flow path and the third flow path, and the second flow path is connected to the third flow path. When the switching device switches the connection state from one of the first state and the second state to the other state during the heating operation, the switching device performs an action of switching the connection state from the third state to the other state after switching the connection state from the one state to the third state.

[0006] According to the present disclosure, it is possible to suppress a decrease in air-conditioning comfort in the vehicle interior. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals represent like parts, and in which:

[0008] Figure 1 It is a diagram showing an example of the overall configuration of a thermal management system (heating system) according to the embodiment.

[0009] Figure 2 This is a diagram for explaining control of a five-way valve by an ECU (Electronic Control Unit) in the embodiment.

[0010] Figure 3 It is a diagram for explaining control of a five-way valve in a comparative example.

[0011] Figure 4 This is a timing chart for explaining switching of the connection states between the flow paths when cooling of the battery starts during the heating operation.

[0012] Figure 5This is a flowchart showing a processing procedure for controlling the switching of the connection states between the flow paths using the five-way valve when the cooling of the battery starts.

[0013] Figure 6 This is a timing chart for explaining control of the five-way valve when cooling of the battery during the heating operation is completed.

[0014] Figure 7 This is a flowchart showing a processing procedure for controlling the switching of the connection states between the flow paths using the five-way valve when the cooling of the battery is completed. DETAILED DESCRIPTION

[0015] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The same or corresponding parts in the drawings are denoted by the same reference numerals and their description will not be repeated.

[0016] Figure 1 1 is a diagram showing an example of the overall configuration of a thermal management system (heating system) according to an embodiment. Figure 1 The thermal management system 1 is mounted on a vehicle 5 . The vehicle 5 is an electric vehicle such as an electric vehicle (BEV: Battery Electric Vehicle). The thermal management system 1 includes an ECU 50 and a thermal management circuit 100 .

[0017] The ECU 50 includes a CPU (Central Processing Unit) 51 and a memory 52. ​​The CPU 51 performs various calculations. The memory 52 includes a ROM (Read Only Memory) and a RAM (Random Access Memory). The ROM stores programs executed by the CPU 51. The ECU 50 controls the thermal management circuit 100 by outputting control instructions corresponding to the sensor values ​​from the thermal management circuit 100 to the thermal management circuit 100.

[0018] The thermal management circuit 100 is configured to flow a heat medium (refrigerant). The thermal management circuit 100 includes a HT (High Temperature) circuit 110, a radiator 120, a LT (Low Temperature) circuit 130, a water-cooled condenser 141, a cooler (cooling device) 142, a heat pump cycle (HPC) 150, a battery circuit 160, a five-way valve 180 having ports P1 to P5, and temperature sensors 192 to 195.

[0019] The HT circuit 110 includes a water pump (W / P) 111, a heater 112, a three-way valve 113, and a heater core 114. The radiator 120 includes a high temperature (HT) radiator 121 and a low temperature (LT) radiator 122. The LT circuit 130 includes a flow path FP3, a W / P 131, and a PCU (Power Control Unit) 133. The HPC 150 includes a compressor 151, expansion valves 152, 155, an evaporator 153, and an EPR (Evaporative Pressure Regulator) 154. The battery circuit 160 includes flow paths FP1, FP2, a W / P 161, a battery 163, a connection portion 165, and a flow path BP.

[0020] The heat medium can flow in each of the flow paths FP1 and FP2. The flow path FP1 is a flow path from the port P1 to the connection portion 165. The flow path FP2 is a flow path from the port P2 to the connection portion 165. The W / P111 circulates the heat medium in the HT circuit 110. The water-cooled condenser 141 heats the heat medium of the HT circuit 110 by receiving the heat released from the heat medium of the HPC150. The heater 112 heats the heat medium of the HT circuit 110. The three-way valve 113 switches the flow destination of the heat medium between the heater core 114 and the HT radiator 121. The heater core 114 heats the air blown into the vehicle interior by heat exchange between the heat medium of the HT circuit 110 and the air. As a result, the vehicle interior is heated. The HT circuit 110 is a heating circuit that heats the vehicle interior.

[0021] The LT radiator 122 is provided in the flow path FP3. The flow path FP3 is a flow path from the port P3 to the port P4, and can allow the heat medium to flow. The LT radiator 122 functions as a heat absorbing device that absorbs heat from the outside air when the temperature of the heat medium in the flow path FP3 is lower than the temperature of the outside air of the vehicle 5. The W / P 131 circulates the heat medium in the flow path FP3. The PCU 133 converts the DC power from the battery 163 into AC power and supplies it to the driving motor of the vehicle 5.

[0022] The water-cooled condenser 141 releases heat from the heat medium of the HPC 150 to the heat medium of the HT circuit 110. The cooler 142 is provided in the flow path FP2, and performs heat exchange between the heat medium of the HPC 150 and the heat medium of the battery circuit 160 (flow path FP2).

[0023] The heat medium (gas phase refrigerant or liquid phase refrigerant) of HPC150 circulates in a circuit passing through evaporator 153 or a circuit passing through water-cooled condenser 141. HPC150 is configured to receive heat from the heat medium of flow path FP2 via cooler 142 and transfer heat to HT circuit 110 for heating operation.

[0024] The compressor 151 compresses the gas phase refrigerant circulating in the HPC150. The rotation speed of the compressor 151 is controlled according to the deviation between the target value and the current value of the blow-out temperature. The water-cooled condenser 141 condenses the gas phase refrigerant into a liquid phase refrigerant by releasing heat from the gas phase refrigerant that is compressed to a high temperature and high pressure. The high temperature and high pressure refrigerant compressed by the compressor 151 dissipates heat to the heat medium (warm water) circulating in the HT circuit 110 through heat exchange in the water-cooled condenser 141. The air (heating air) heated by the heat of the heated warm water dissipating heat in the heater core 114 is blown into the vehicle interior from the blow-out port to heat the vehicle interior. The expansion valves 152 and 155 respectively decompress the liquid phase refrigerant by expanding the high pressure liquid phase refrigerant. The EPR154 adjusts the pressure in the evaporator 153 to be approximately constant by controlling the flow rate of the heat medium flowing into the evaporator 153. The cooler 142 evaporates the liquid phase refrigerant decompressed by the expansion valve 155. As a result, heat is taken away from the heat medium circulating in the battery circuit 160 , and the heat medium is cooled.

[0025] The heat medium circulating in the battery circuit 160 flows in one or both of the first circulation circuit and the second circulation circuit. The first circulation circuit refers to the path of W / P161-cooler 142-five-way valve 180-battery 163-W / P161. The second circulation circuit refers to the path of W / P161-cooler 142-five-way valve 180-flow path BP-W / P161.

[0026] The W / P 161 circulates the heat medium in the battery circuit 160. The cooler 142 cools the heat medium circulating in the battery circuit 160 by exchanging heat between the heat medium circulating in the HPC 150 and the heat medium circulating in the battery circuit 160. The battery 163 is provided in the flow path FP1 and can exchange heat with the heat medium in the flow path FP1. The battery 163 stores electric power for driving the vehicle 5. The battery 163 can be cooled by the heat medium in the flow path FP1.

[0027] The flow path BP is a flow path from the port P5 to the connection portion 165, and can be used to circulate the heat medium. The flow path BP is a bypass flow path for the heat medium to bypass the battery 163. The flow path BP is connected to the connection portion 165. The connection portion 165 is located at a portion downstream of the battery 163 in the flow path FP1 and at a portion upstream of the cooler 142 in the flow path FP2. The flow path BP is configured to be connected to a portion downstream of the LT radiator 122 in the flow path FP3 through the five-way valve 180.

[0028] The five-way valve 180 has ports P1 to P5. Port P1 can be connected to the flow path FP1. Port P2 can be connected to the flow path FP2. Ports P3 and P4 can be connected to the upstream portion and the downstream portion of the flow path FP3 respectively. Port P5 can be connected to the flow path BP. The five-way valve 180 is a switching device that switches the connection state between the flow paths FP1 to FP3 and BP, and is controlled by the ECU 50.

[0029] The temperature sensor 192 detects the radiator water temperature Tr, which is the temperature of the heat medium flowing in the LT radiator 122 (the temperature of the heat medium in the flow path FP3). The radiator water temperature Tr is equivalent to the temperature of the heat medium in the downstream portion of the LT radiator 122 in the flow path FP3. The temperature sensor 193 detects the temperature of the heat medium in the flow path FP2 (the cooler water temperature Tc). In this example, the cooler water temperature Tc is equivalent to the temperature of the heat medium in the upstream portion of the cooler 142 in the flow path FP2. The temperature sensor 194 detects the temperature of the heat medium in the flow path FP1 (the battery water temperature Tb). The temperature sensor 195 detects the temperature of the heat medium flowing in the PCU 133 (the powertrain water temperature Tp). The powertrain water temperature Tp may also be used as the temperature of the heat medium in the flow path FP3.

[0030] Figure 2 1 is a diagram for explaining the control of the five-way valve 180 by the ECU 50 in the embodiment. Figure 2 ECU 50 controls five-way valve 180 so that the connection state between flow paths FP1, FP2, FP3 and BP becomes the first state, the second state or the third state.

[0031] The first state ( Figure 2 The upper part of ) corresponds to the connection state between the various flow paths when the outside air is used as a heating heat source. In the first state, flow path FP1 is disconnected from flow paths FP2, FP3, and BP, flow path FP2 is connected to flow paths FP3 and BP, and flow path FP3 is connected to flow path BP. The heat medium passing through cooler 142 circulates in a closed loop formed by flow paths FP2, FP3, and BP. ECU50 achieves the first state by controlling the five-way valve 180 in such a way that port P1 is disconnected from ports P2 to P5, ports P2 and P3 are connected, and ports P4 and P5 are connected. In the first state, HPC150 performs heating operation and does not cool the battery 163.

[0032] In the first state, flow path FP1 is disconnected from flow paths FP2, FP3, and BP. Therefore, the battery water temperature Tb may deviate from the cooler water temperature Tc or the radiator water temperature Tr (or the powertrain water temperature Tp). For example, when outside air is used as a heating heat source in a low temperature environment in winter, the radiator water temperature Tr is lower than the outside air temperature (for example, 0°C). As a result, the battery water temperature Tb in the first state may be significantly higher than the radiator water temperature Tr. The deviation between the radiator water temperature Tr and the battery water temperature Tb becomes more significant when the cooling start temperature of the battery 163 is set higher from the perspective of energy saving and the cooling frequency of the battery 163 is low.

[0033] The second state ( Figure 2 ) corresponds to the connection state between the various flow paths when the battery 163 is used as a heating heat source. In the second state, flow path FP1 is connected to flow path FP2 and is cut off from flow path FP3, flow path FP2 is cut off from flow path FP3, and flow path FP3 is cut off from flow path BP. The heat medium passing through the cooler 142 circulates in the closed loop (single-dotted line) formed by flow paths FP1 and FP2. ECU50 achieves the second state by controlling the five-way valve 180 in such a way that ports P1 and P2 are connected, ports P3 and P4 are connected, and port P5 is cut off from ports P1 to P4. In the second state, the heat of the battery 163 is transmitted via the heat medium of flow path FP1, the heat medium of flow path FP2, the cooler 142, and the HPC150 ( Figure 1 ) is supplied to the HT circuit 110 (HPC 150 performs heating operation) and cools the battery 163.

[0034] In the second state, the flow path FP3 is disconnected from the flow paths FP1, FP2, and BP. Therefore, the radiator water temperature Tr (or the powertrain water temperature Tp) may deviate from the battery water temperature Tb or the cooler water temperature Tc.

[0035] When cooling of the battery 163 during the heating operation starts or ends, the ECU 50 controls the five-way valve 180 so that the connection state between each flow path is switched from one of the first state and the second state to the other state. For example, when cooling of the battery 163 starts, the ECU 50 controls the five-way valve 180 so that the connection state is switched from the first state to the second state in order to change the heating heat source from the outside air to the battery 163. When cooling of the battery 163 ends, the ECU 50 controls the five-way valve 180 so that the connection state is switched from the second state to the first state in order to change the heating heat source from the battery 163 to the outside air.

[0036] As described above, when the ECU 50 switches the connection state from the first state to the second state or from the second state to the first state, the cooler water temperature Tc may change suddenly and the air-conditioning comfort may be reduced (described in detail later).

[0037] Therefore, when the connection state between the flow paths is switched from one of the first state and the second state to the other state during the heating operation (when the cooling of the battery 163 is started or ended), the ECU 50 controls the five-way valve 180 to perform a specific switching operation. This operation is to switch from the above-mentioned one state to the third state ( Figure 2 The action of switching the connection state from the third state to the state of the other party mentioned above after switching the connection state)

[0038] In the third state, flow path FP1 is connected to flow paths FP2, FP3, and BP, flow path FP2 is connected to flow paths FP3 and BP, and flow path FP3 is connected to flow path BP. ECU 50 controls five-way valve 180 so that ports P1, P4, and P5 are connected and ports P2 and P3 are connected, thereby achieving the third state.

[0039] In the third state, paths R1 and R2 are formed. Path R1 is a path for the heat medium to flow into cooler 142 through flow paths FP3, BP and connection 165. Path R2 is a path for the heat medium to flow into cooler 142 through flow paths FP3, FP1 and connection 165.

[0040] The aforementioned specific switching action includes a first action performed when the cooling of the battery 163 starts and a second action performed when the cooling of the battery 163 ends. The first action is an action of switching the connection state from the third state to the second state after switching the connection state from the first state to the third state (shaded arrow). The second action is an action of switching the connection state from the third state to the first state after switching the connection state from the second state to the third state (open arrow).

[0041] According to the first action, when the cooling of the battery 163 starts, the connection state temporarily takes the third state before switching from the first state to the second state. In the third state, the closed loop (cooler-battery circulation loop) circulated by the heat medium of the cooler 142 and the battery 163 includes the flow path FP3, so it is larger than the cooler-battery circulation loop (single-point dashed line) in the second state. Therefore, the amount of heat medium in the cooler-battery circulation loop in the third state is more than the amount of heat medium in the cooler-battery circulation loop in the second state. Therefore, the temperature change of the heat medium of the cooler-battery circulation loop just after switching the first state to the third state (accompanied by the temperature change of the connection of the flow paths FP1 and FP2) is smaller than the temperature change of the heat medium of the cooler-battery circulation loop just after switching the first state directly to the second state. Thus, the influence of the heat medium of the flow path FP2 on the heat of the battery 163 at the beginning of the cooling of the battery 163 can be reduced. Therefore, the change of the cooler water temperature Tc can be reduced.

[0042] According to the second action, when the cooling of the battery 163 is completed, the connection state temporarily takes the third state before switching from the second state to the first state. In the third state, the closed loop (cooler-radiator circulation loop) circulated by the heat medium of the cooler 142 and the LT radiator 122 includes the flow path FP1, so it is larger than the cooler-radiator circulation loop (solid line) in the first state. Therefore, the amount of heat medium of the cooler-radiator circulation loop in the third state is more than the amount of heat medium of the cooler-radiator circulation loop in the first state. Therefore, the temperature change of the heat medium of the cooler-battery circulation loop just after switching the second state to the third state (accompanied by the temperature change of the connection of the flow paths FP2 and FP3) is smaller than the temperature change of the heat medium of the cooler-battery circulation loop just after switching the second state directly to the first state. As a result, it is possible to reduce the influence of the heat medium of the flow path FP2 on the heat medium of the flow path FP3 at the end of the cooling of the battery 163. Therefore, the change of the cooler water temperature Tc can be reduced.

[0043] In this way, according to the first action and the second action, the rapid change of the cooler water temperature Tc can be reduced. As a result, the reduction in air-conditioning comfort in the vehicle interior can be suppressed. In addition, the operation of the heater 112 for compensating for the reduction in air-conditioning comfort caused by the rapid change of the cooler water temperature Tc is not required, and the highly efficient HPC150 can be effectively utilized. Therefore, the power consumption when heating the vehicle interior can be saved.

[0044] In the embodiment, in the third state, both the path R1 and the path R2 are formed. Therefore, the heat medium of the flow path FP3 flows into the cooler 142 through both the flow paths FP1 and FP2. In this case, the heat medium in the downstream portion of the flow path FP1 relative to the battery 163 is mixed with the heat medium of the flow path BP at the connection portion 165, and the mixed heat medium flows into the cooler 142. The temperature of the mixed heat medium is closer to the cooler water temperature Tc before the switching of the connection state than the temperature of the heat medium at the connection portion 165 in the case where the heat medium flows into the cooler 142 only through one of the paths R1 and R2. Therefore, compared with the above situation, the change of the cooler water temperature Tc can be more effectively reduced.

[0045] For example, when the cooling of the battery 163 starts (first state → third state), assuming that the heat medium flows into the cooler 142 only through the path R1, the relatively high-temperature heat medium that passes through the battery 163 only in the flow path FP1 flows into the cooler 142 through the connection portion 165. On the other hand, in the embodiment, the relatively low-temperature heat medium supplied from the flow path FP3 through the flow path BP also flows into the connection portion 165 and mixes with the relatively high-temperature heat medium at the connection portion 165. As a result, the mixed medium of medium temperature flows into the cooler 142, so compared with the above-mentioned case where only the high-temperature heat medium flows into the cooler 142, the rapid change of the cooler water temperature Tc can be more effectively reduced.

[0046] Similarly, when the cooling of the battery 163 is completed (second state → third state), assuming that the heat medium flows into the cooler 142 only through the path R1, the relatively low-temperature heat medium that passes through the battery 163 only in the flow path FP1 flows into the cooler 142 through the connection portion 165. On the other hand, in the embodiment, the relatively high-temperature heat medium supplied from the flow path FP3 through the flow path BP also flows into the connection portion 165 and mixes with the relatively low-temperature heat medium at the connection portion 165. As a result, the medium-temperature heat medium flows into the cooler 142, which can effectively reduce the rapid change of the cooler water temperature Tc.

[0047] Figure 3 1 is a diagram for explaining the control of the five-way valve 180 by the ECU in the comparative example. In the comparative example, when the cooling of the battery 163 during the heating operation starts or ends, the connection state between the flow paths is directly switched from one of the first state and the second state to the other state.

[0048] Reference Figure 3At the start of cooling of the battery 163, the ECU of the comparative example controls the five-way valve 180 in such a way that the connection state between each flow path is directly switched from the first state to the second state (shaded arrow). As a result, the flow path FP2 is connected to the flow path FP1 and is cut off from the flow path FP3. As a result, the heat medium circulating in the cooler 142 no longer circulates in the LT radiator 122, but instead circulates in the battery 163 (circulating in a closed loop formed by the flow paths FP1 and FP2). Therefore, when the battery water temperature Tb deviates from the cooler water temperature Tc at the start of cooling of the battery 163, the cooler water temperature Tc may be affected by the battery water temperature Tb and change sharply just after switching from the first state to the second state.

[0049] When the cooling of the battery 163 is completed, the ECU controls the five-way valve 180 in such a way that the connection state between each flow path is directly switched from the second state to the first state (hollow arrow). As a result, the flow path FP2 is disconnected from the flow path FP1 and connected to the flow path FP3. As a result, the heat medium circulating in the cooler 142 no longer circulates in the battery 163, but instead circulates in the LT radiator 122 (circulating in a closed loop formed by the flow paths FP2, FP3, and BP). Therefore, when the radiator water temperature Tr (powertrain water temperature Tp) deviates from the cooler water temperature Tc at the end of the cooling of the battery 163, the cooler water temperature Tc may be affected by the radiator water temperature Tr and change sharply just after switching from the second state to the first state.

[0050] The rapid change of the cooler water temperature Tc affects the HT circuit 110 via the HPC 150, resulting in a significant change in the temperature at the outlet of the heating air. As a result, the air conditioning comfort in the vehicle interior may be reduced. In order to compensate for the reduction in air conditioning comfort, the heater 112 can also be operated, but compared with the high-efficiency heating using the HPC 150, the power consumption increases.

[0051] As described above, the compressor speed is controlled based on the deviation between the target value and the current value of the temperature at the outlet of the heating air. However, when the amount of heat absorbed by the cooler changes sharply, the compressor speed increases after the expansion of the deviation is detected. In other words, the increase in the compressor speed is delayed relative to the switching timing between the first state and the second state. Therefore, it is difficult to suppress the sharp change in the amount of heat absorbed by the cooler (cooler water temperature Tc) by adjusting the compressor speed after switching from the first state to the second state or from the second state to the first state.

[0052] In addition, when the heat absorption of the cooler changes rapidly, the refrigerant dryness may change and the heat medium may not be completely vaporized by the cooler 142. That is, the heat medium at the inlet of the compressor 151 will be in a gas-liquid mixed phase state (a state where the gas phase refrigerant and the liquid phase refrigerant are mixed). This is not preferable from the perspective of protecting the compressor 151.

[0053] Thus, in the comparative example, when the cooling of the battery 163 starts or ends, problems such as a decrease in air conditioning comfort, an increase in power consumption, and a gas-liquid mixed phase of the heat medium at the inlet of the compressor 151 may occur. Figure 2 ), such problems can be suppressed.

[0054] Figure 4 1 is a timing chart for explaining the switching of the connection states between the flow paths FP1 to FP3 and BP when the cooling of the battery 163 during the heating operation is started. Figure 4 The horizontal axis represents the elapsed time. The vertical axis represents, from the top, the presence / absence of a cooling request for the battery 163, the circuit connected to the cooler 142 (LT circuit 130 / battery circuit 160), the cooler water temperature Tc, the battery water temperature Tb, the radiator water temperature Tr, the powertrain water temperature Tp, and the connection status between the various flow paths.

[0055] The solid line and the dashed line respectively show the time changes of each parameter in the embodiment and the comparative example. In the comparative example, the connection state is directly switched from the first state to the second state.

[0056] During the period TP1 before the moment ta, the connection state is the first state. At the moment ta, the battery water temperature Tb rises to the cooling start temperature TS, and a cooling request for the battery 163 is generated. The ECU50 of the embodiment controls the five-way valve 180 in a manner of performing the first action in response to the cooling request. Specifically, after the ECU50 switches the connection state between each flow path from the first state to the third state at the moment ta, the third state is maintained during the period TP2. The period TP2 lasts until the cooler water temperature Tc rises by the reference temperature ΔPT1 (until the moment tb). At the moment tb, the ECU50 switches the connection state from the third state to the second state, and maintains the second state during the period TP3.

[0057] The temperature difference between the battery water temperature Tb and the cooler water temperature Tc or the radiator water temperature Tr (powertrain water temperature Tp) is also expressed as a temperature difference ΔT1 (=|Tb-Tc|, |Tb-Tr| or |Tb-Tp|). The temperature difference ΔT1 is related to the change in the cooler water temperature Tc when the cooling of the battery 163 starts. For example, when the temperature difference ΔT1 is as large as or greater than the threshold value TH1 in the first state before the cooling of the battery 163 starts, when the connection state is directly switched from the first state to the second state when the cooling of the battery 163 starts, it is predicted that the cooler water temperature Tc changes sharply. In the case where this is not the case, since the temperature difference ΔT1 is small, it is predicted that the cooler water temperature Tc will not change sharply when switching.

[0058] Therefore, when the connection state is switched from the first state to the second state, the ECU 50 may control the five-way valve 180 to perform the first action when the temperature difference ΔT1 is greater than the threshold value TH1. On the other hand, when the temperature difference ΔT1 is less than the threshold value TH1, the ECU 50 may control the five-way valve 180 to directly switch the connection state from the first state to the second state without switching from the first state to the third state.

[0059] According to such control, when it is predicted that the cooler water temperature Tc will not change rapidly, it is possible to immediately start heating the vehicle interior using the battery 163 as a heating heat source.

[0060] Figure 5 1 is a flowchart showing a control process sequence for switching the connection state between the flow paths using the five-way valve 180 when the battery 163 starts to cool. The process shown in the flowchart starts in response to a request for cooling the battery 163. Hereinafter, the step is abbreviated to S.

[0061] Reference Figure 5 In S105 , the ECU 50 determines whether the temperature difference ΔT1 is equal to or greater than a threshold value TH1 ( S105 ).

[0062] When the temperature difference ΔT1 is less than the threshold value TH1 (“No” in S105), the ECU 50 controls the five-way valve 180 in a manner that directly switches the connection state of the flow paths FP1 to FP3 and BP from the first state to the second state without switching from the first state to the third state (S120). When this is not the case (“Yes” in S105), the ECU 50 controls the five-way valve 180 in a manner that switches the connection state of the flow paths FP1 to FP3 and BP from the first state to the third connection state (S110). Thereafter, the ECU 50 controls the five-way valve 180 in a manner that switches the connection state of the flow paths FP1 to FP3 and BP from the third state to the second connection state (S115).

[0063] Figure 6 1 is a timing chart for explaining the control of the five-way valve 180 when the cooling of the battery 163 during the heating operation is completed. Figure 6 , the parameters of the horizontal and vertical axes are Figure 4 The parameters shown are the same.

[0064] The solid line and the dashed-dotted line respectively show the time changes of the parameters in the embodiment and the comparative example. In the comparative example, the connection state is directly switched from the second state to the first state.

[0065] During the period TP1a before the moment tc, the connection state is the second state. At the moment tc, the cooling request of the battery 163 disappears. Thus, the ECU50 of the embodiment controls the five-way valve 180 in a manner of performing the second action. Specifically, after the ECU50 switches each connection state from the second state to the third state at the moment tc, the third state is maintained during the period TP2a. The period TP2a lasts until the cooler water temperature Tc decreases by the reference temperature ΔPT2 (until the moment td). At the moment td, the ECU50 switches the connection state from the third state to the first state, and maintains the first state during the period TP3a.

[0066] In this example, the cooler water temperature Tc at the end of battery cooling is higher than that at the start of battery cooling ( Figure 4 ) is low, but even if this is not the case, the rapid change of the cooler water temperature Tc can be suppressed by the second action.

[0067] The temperature difference between the radiator water temperature Tr (powertrain water temperature Tp) and the battery water temperature Tb or the cooler water temperature Tc is also expressed as a temperature difference ΔT2 (=|Tr-Tb|, |Tr-Tc|, |Tp-Tb| or |Tp-Tc|). The temperature difference ΔT2 is related to the change in the cooler water temperature Tc when the cooling of the battery 163 is completed. For example, when the temperature difference ΔT2 is as large as or greater than the threshold value TH2 in the second state before the cooling of the battery 163 is completed, when the connection state is directly switched from the second state to the first state at the end of the cooling of the battery 163, it is predicted that the cooler water temperature Tc changes sharply. In the case where this is not the case, since the temperature difference ΔT2 is small, it is predicted that the cooler water temperature Tc will not change sharply.

[0068] Therefore, when the connection state is switched from the second state to the first state, the ECU 50 may control the five-way valve 180 so as to perform the second action when the temperature difference ΔT2 is greater than the threshold value TH2. On the other hand, when the temperature difference ΔT2 is less than the threshold value TH2, the ECU 50 may control the five-way valve 180 so as to directly switch the connection state from the second state to the first state without switching from the second state to the third state.

[0069] According to such control, when it is predicted that the cooler water temperature Tc will not change rapidly, the heating heat source can be switched from the battery 163 to the outside air in advance.

[0070] Figure 7 This is a flowchart showing a processing procedure for controlling the switching of the connection states between the flow paths using the five-way valve 180 when the cooling of the battery 163 is completed. The processing shown in this flowchart starts in response to the disappearance of the cooling request for the battery 163.

[0071] Reference Figure 7 In S205 , the ECU 50 determines whether the temperature difference ΔT2 is equal to or greater than a threshold value TH2 ( S205 ).

[0072] When the temperature difference ΔT2 is less than the threshold value TH2 (“No” in S205), the ECU 50 controls the five-way valve 180 in a manner that the connection state of the flow paths FP1 to FP3 and BP is directly switched from the second state to the first state without switching from the second state to the third state (S220). When this is not the case (“Yes” in S205), the ECU 50 controls the five-way valve 180 in a manner that the connection state of the flow paths FP1 to FP3 and BP is switched from the second state to the third connection state (S210). Thereafter, the ECU 50 controls the five-way valve 180 in a manner that the connection state of the flow paths FP1 to FP3 and BP is switched from the third state to the first connection state (S215).

[0073] As described above, according to the embodiment, it is possible to suppress a decrease in air-conditioning comfort in the vehicle interior.

[0074] <Other Modifications>

[0075] When the heat management circuit 100 includes an interior condenser, the heat of the heat medium of the battery circuit 160 may be dissipated to the vehicle interior via the cooler 142 and the interior condenser to heat the vehicle interior.

[0076] The embodiments disclosed this time should be considered as illustrative in all aspects and not restrictive. The scope of the present invention is indicated by the claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the claims.

Claims

1. A heating system, mounted on a vehicle, wherein: The heating system comprises: The first flow path, the second flow path and the third flow path are capable of allowing the heat medium to flow; an electric storage device capable of exchanging heat with the heat medium in the first flow path; a cooling device, disposed in the second flow path; a heat absorbing device disposed in the third flow path and configured to absorb heat from air outside the vehicle; A heating circuit for heating a cabin of the vehicle; a heat pump cycle for performing a heating operation in which the heat medium in the second flow path receives heat via the cooling device and transfers the heat to the heating circuit; as well as a switching device configured to switch the connection state among the first flow path, the second flow path, and the third flow path, The connection status includes: In a first state, the first flow path is separated from the second flow path and the third flow path, and the second flow path is connected to the third flow path; a second state in which the first flow path is connected to the second flow path and is cut off from the third flow path, and the second flow path is cut off from the third flow path; and In a third state, the first flow path is connected to the second flow path and the third flow path, and the second flow path is connected to the third flow path. When the switching device switches the connection state from one of the first state and the second state to the other state during the heating operation, the switching device performs the action of switching the connection state from the third state to the other state after switching the connection state from the one state to the third state.

2. The heating system according to claim 1, When the temperature difference between the temperature of the heat medium in the second flow path or the temperature of the heat medium in the third flow path and the temperature of the heat medium in the first flow path is set as a first temperature difference, When the switching device switches the connection state from the first state to the second state, When the first temperature difference is greater than a first threshold, the action is performed. When the first temperature difference is less than the first threshold, the connection state is switched from the first state to the second state without switching from the first state to the third state.

3. The heating system according to claim 1, When the temperature difference between the temperature of the heat medium in the first flow path or the temperature of the heat medium in the second flow path and the temperature of the heat medium in the third flow path is set as the second temperature difference, When the switching device switches the connection state from the second state to the first state, When the second temperature difference is greater than a second threshold, the action is performed. When the second temperature difference is less than the second threshold, the connection state is switched from the second state to the first state without switching from the second state to the third state.

4. The heating system according to any one of claims 1 to 3, The heating system further comprises a bypass flow path. The bypass flow path is configured to be connected to a connection portion and to be connectable to a portion of the third flow path downstream of the heat absorbing device, the connection portion being located at a portion of the first flow path downstream of the power storage device and at a portion of the second flow path upstream of the cooling device, The third state includes a state in which a first path and a second path are formed, wherein the first path is a path through which the heat medium flows into the cooling device through the third flow path, the bypass flow path, and the connecting portion, and the second path is a path through which the heat medium flows into the cooling device through the third flow path, the first flow path, and the connecting portion.

5. The heating system according to claim 4, The switching device has: a first port, connectable to the first flow path; a second port capable of being connected to the second flow path; a third port capable of being connected to a portion of the third flow path that is upstream of the heat sink; a fourth port capable of being connected to a portion of the third flow path that is downstream of the heat absorbing device; as well as a fifth port, connectable to the bypass flow path, The first state includes a state in which the first port is disconnected from the second port to the fifth port, the second port is communicated with the third port, and the fourth port is communicated with the fifth port. The second state includes a state in which the first port is communicated with the second port, the third port is communicated with the fourth port, and the fifth port is disconnected from the first port to the fourth port. The third state includes a state in which the first port is in communication with the fourth port and the fifth port, and the second port is in communication with the third port.

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