JP2014037181A - Thermal management system for electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a battery temperature from rising when a compressor during the refrigeration cycle fails.SOLUTION: A thermal management system 100 for an electric vehicle comprises: a refrigerant loop for an air conditioner; a refrigerant loop 50 for a battery that circulates a refrigerant for a battery among a battery 1 for storing electricity supplied to an electric motor 33, an evaporation portion 17 and a heat exchanger 56, provided in a drafter 6 for ventilation exhausting air in a vehicle interior to outside of the vehicle interior, that exchanges heat between air flowing in the drafter 6 and the refrigerant for a battery; switching means 58 and 59 capable of switching the refrigerant loop 50 for a battery between a state of flowing on the heat exchanger 56 and a state of circumventing the heat exchanger 56; and thermal management control means 70 that when a compression portion 11 fails, switches the refrigerant loop 50 for a battery to the state of flowing on the heat exchanger 56 and releases heat of the refrigerant for a battery to air in the drafter 6 by using the heat exchanger 56.

Description

  The present invention relates to an electric vehicle thermal management system mounted on an electric vehicle.

  Since the electric vehicle that travels by the driving force of the electric motor is not equipped with an engine, the exhaust heat of the engine cannot be used during heating. Further, even in an electric vehicle equipped with an engine such as a hybrid vehicle, the engine is not always operated, so that the amount of heat during heating is insufficient. Therefore, during heating, the passenger compartment temperature is raised by an air conditioner configured by a refrigerant cycle provided with an electric compressor.

  However, since the electric power stored in the battery is consumed as much as the air conditioner is operated, the cruising range of the vehicle is reduced.

  Patent Document 1 discloses an air conditioning system that includes a cooling water circuit that cools a battery separately from a refrigerant cycle that constitutes an air conditioner, and that can exchange heat between the refrigerant and the cooling water. This air conditioning system heats the battery during charging, and uses the heat stored in the battery when the vehicle is operating and heating is used.

JP 2011-68348 A

  However, the air conditioning system of Patent Document 1 cannot dissipate heat from the cooling water circuit that cools the battery when the compressor of the refrigerant cycle fails and stops. As a result, when the compressor fails, the battery temperature may rise and the battery may deteriorate.

  In addition, in order to suppress an increase in battery temperature, it may be possible to immediately stop the driving of the electric motor when the compressor breaks down. However, in this case, the vehicle can be run while the driving of the electric motor is stopped. become unable.

  The present invention has been made in view of such technical problems, and an object thereof is to provide a thermal management system for an electric vehicle that can suppress an increase in battery temperature when a compressor in a refrigerant cycle fails. To do.

  According to an aspect of the present invention, there is provided a thermal management system for a vehicle used in an electric vehicle driven by an electric motor, the compressor for compressing a refrigerant for an air conditioner, and heat for the air conditioner by radiating heat of the refrigerant for the air conditioner. An air conditioner having a condensing unit for condensing the refrigerant, a decompression unit for expanding and depressurizing the air conditioner refrigerant, and an evaporating unit for absorbing heat from the air conditioner refrigerant to evaporate the air conditioner refrigerant, and circulating the air conditioner refrigerant A refrigerant loop for the battery, a battery for storing the electric power supplied to the electric motor, an evaporator common to the refrigerant loop for the air conditioner, and a ventilation drafter for releasing the air in the passenger compartment to the outside of the passenger compartment A heat exchanger that circulates between the heat exchanger that exchanges heat between the air that flows in the drafter and the battery refrigerant, and that exchanges heat between the battery refrigerant loop and the battery refrigerant loop. Switching means that can be switched between a state of flowing through the air conditioner and a state of bypassing the heat exchanger, and the compressor refrigerant unit can no longer compress the air conditioner refrigerant, the battery refrigerant loop is connected to the heat exchanger. There is provided a heat management system for an electric vehicle, comprising: heat management control means for switching to a flowing state and radiating the heat of the battery refrigerant to the air in the drafter by a heat exchanger.

  According to the above aspect, since the heat of the battery refrigerant can be dissipated in the heat exchanger even if the compressor section fails and the circulation of the air conditioner refrigerant stops, the battery temperature rises when the compressor section fails. Can be suppressed.

1 shows an overall configuration of a thermal management system for an electric vehicle according to an embodiment of the present invention. 1 is a side view showing a vehicle to which an electric vehicle thermal management system is applied. It is a control system figure of the thermal management system for electric vehicles. It is the flowchart which showed the processing content of the thermal management system for electric vehicles. It is the flowchart which showed the processing content of the thermal management system for electric vehicles. It is the flowchart which showed the processing content of the thermal management system for electric vehicles. The operation state of the thermal management system for electric vehicles at the time of heating is shown. The operation state of the thermal management system for electric vehicles at the time of air conditioning is shown. The operation state of the thermal management system for electric vehicles at the time of compressor abnormality is shown.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 shows the overall configuration of a thermal management system 100 for an electric vehicle according to the present invention.

  The electric vehicle thermal management system 100 includes an air conditioner loop 10, a high water temperature loop 30, and a low water temperature loop 50.

  The air conditioner loop 10 will be described.

  The air conditioner loop 10 is a refrigerant circuit constituting a refrigeration cycle in which a refrigerant (for example, HFC134a) is circulated in the order of the compressor 11, the condenser 12, the expansion valve 13, and the evaporator 14.

  The compressor 11 is driven by an electric motor, compresses refrigerant gas, and discharges high-temperature and high-pressure compressed refrigerant gas.

  The condenser 12 exchanges heat between the compressed refrigerant gas and the outside air, and dissipates the heat of the compressed refrigerant gas to the outside air, thereby cooling the condensed refrigerant gas and condensing it into a liquid refrigerant.

  The expansion valve 13 expands the high-pressure liquid refrigerant into a low-pressure liquid refrigerant. The expansion valve 13 is a temperature-sensitive expansion valve (TXV), and controls the amount of refrigerant flowing into the evaporator 14 so that the degree of superheat at the outlet of the evaporator 14 becomes a predetermined state set in advance.

  The evaporator 14 performs heat exchange between the liquid refrigerant and the passenger compartment air, absorbs the heat of the passenger compartment air, cools the passenger compartment air, and evaporates the liquid refrigerant to produce a refrigerant gas.

  The air conditioner loop 10 further includes a bypass flow path 15 that bypasses the downstream side of the compressor 11 and the downstream side of the condenser 12, a water condenser 16 provided in the middle of the bypass flow path 15, and a chiller 17 provided in parallel with the evaporator 14. And a flow path 19 through which the refrigerant flows through the expansion valve 18.

  The water condenser 16 is a heat exchanger that is provided in the high water temperature loop 30 and performs heat exchange between the refrigerant flowing through the bypass passage 15 and the refrigerant flowing through the high water temperature loop 30. The chiller 17 is a heat exchanger that is provided in the low water temperature loop 50 and performs heat exchange between the refrigerant of the air conditioner loop 10 and the low water temperature loop 50. Similarly to the evaporator 14, the refrigerant flows into and out of the chiller 17 through a temperature-sensitive expansion valve (TXV).

  The air conditioner loop 10 further includes a three-way valve 20 that can switch the flow path so that the refrigerant discharged from the compressor 11 flows to at least one of the condenser 12 side and the bypass flow path 15 side, and the refrigerant flowing through the bypass flow path 15 is on the condenser 12 side. A check valve 21 for preventing the refrigerant from flowing backward, an evaporator electromagnetic valve 22 capable of opening and closing the refrigerant flow path to the evaporator 14, and a chiller electromagnetic valve 23 capable of opening and closing the refrigerant flow path to the chiller 17.

  Next, the high water temperature loop 30 will be described.

  The high water temperature loop 30 circulates cooling water (such as antifreeze liquid) in the order of the radiator pump 31, the radiator 32, and the motor 33, and in the order of the H / C pump 34, the heater core 35, and the water condenser 16. That is, the high water temperature loop 30 is a cooling water circuit that radiates heat absorbed by at least one of the motor 33 and the water condenser 16 and at least one of the radiator 32 and the heater core 35.

  The radiator pump 31 sends cooling water to the radiator 32. The radiator 32 performs heat exchange between the cooling water and the air outside the passenger compartment, and cools the cooling water by releasing the heat of the cooling water to the outside of the passenger compartment. The motor 33 is an electric motor for driving the vehicle, and receives power supplied from the battery 1 to drive the vehicle.

  The H / C pump 34 sends the cooling water to the heater core 35. The heater core 35 exchanges heat between the cooling water and the vehicle interior air, and releases the heat of the cooling water into the vehicle interior to heat the vehicle interior air and cool the cooling water. The water condenser 16 is a heat exchanger that exchanges heat between the refrigerant of the air conditioner loop 10 and the cooling water of the high water temperature loop 30, and heat is transferred from the refrigerant to the cooling water.

  The high water temperature loop 30 is further connected to the downstream side of the water condenser 16 and the upstream side of the radiator pump 31 to bypass the motor 33, and the cooling water downstream of the water condenser 16 is supplied to the motor 33 side. A water switching valve 37 capable of switching the flow path so as to flow to at least one of the bypass flow path 36 side.

  Next, the low water temperature loop 50 will be described.

  The low water temperature loop 50 circulates cooling water (for example, antifreeze liquid) in the order of the battery pump 51, the sub radiator 56, the DC / DC converter 52, the inverter 53, the hot water heater 54, the water jacket 55, and the chiller 17.

  The battery pump 51 sends the cooling water to the sub radiator 56. The sub-radiator 56 is provided in a draft duct 6 disposed at the rear of the vehicle, and performs heat exchange between vehicle interior air discharged to the outside of the vehicle through the draft duct 6 and cooling water in the low water temperature loop 50. .

  As shown in FIG. 2, the draft duct 6 is a ventilation path that releases vehicle interior air to the outside of the vehicle for ventilation, and a pressure difference between the vehicle interior and the atmosphere that occurs when air outside the vehicle is introduced by the air conditioning unit. To release the vehicle interior air to the outside of the vehicle. The inlet 6a of the draft duct 6 is provided, for example, on the side of a rear parcel or rear seat, and the outlet 6b is provided on the back side of the rear bumper.

  The DC / DC converter 52 steps down the power supplied from the battery 1 to 12 V, for example, and outputs it to a power supply system (such as a sub-battery) different from the drive system (such as the motor 33 and the inverter 53). The inverter 53 converts the DC power of the battery 1 into AC power according to the required driving force of the vehicle and supplies it to the motor 33. The battery 1 has a heat insulating structure that can store electric power supplied to the motor 33 for driving the vehicle and ensure heat insulating properties between the battery 1 and the outside air.

  The hot water heater 54 is a PTC heater, for example, and generates heat by the power supplied from the battery 1 to heat the cooling water. The water jacket 55 is a heat exchanger that performs heat exchange between the cooling water and the battery 1, and is provided adjacent to the battery 1 so that a contact area with the battery module is increased. The chiller 17 is a heat exchanger that exchanges heat between the cooling water in the low water temperature loop 50 and the refrigerant in the air conditioner loop 10, and heat is transferred from the refrigerant to the cooling water.

  The low water temperature loop further includes a bypass passage 57 that sends the cooling water sent from the battery pump 51 to the DC / DC converter 52 by bypassing the sub-radiator 56, and a bypass electromagnetic valve 58 that can open and close the bypass passage 57. And a sub RAD electromagnetic valve 59 for opening and closing a flow path for flowing the cooling water to the sub radiator 56 side.

  The electric vehicle thermal management system 100 includes the above three loops, and heat is transferred between the loops.

  FIG. 2 is a side view showing an example of a vehicle to which the electric vehicle thermal management system 100 is applied.

  Since the high water temperature loop 30 becomes high temperature due to exhaust heat generated by the motor 33 during traveling and heat absorbed from the water condenser 16, the high water temperature loop 30 is disposed at the forefront of the vehicle so that the cooling water can be efficiently cooled by the traveling wind of the vehicle. Is done.

  Since the air conditioner loop 10 includes the evaporator 14 constituting the air conditioning unit, the air conditioner loop 10 is disposed at a position in front of the vehicle and close to the vehicle interior.

  The low water temperature loop 50 circulates through the battery 1 mounted at the center lower part of the vehicle, the chiller 17 that exchanges heat with the refrigerant of the air conditioner loop 10, and the sub-radiator 56 provided in the draft duct 6. To the last part.

  Here, the transfer of heat between the vehicle and the air outside the passenger compartment will be described.

  The radiator 32 of the high water temperature loop 30 and the condenser 12 of the air conditioner loop 10 are disposed at a position for receiving the traveling wind during vehicle traveling. Thus, it is possible to dissipate heat from the radiator 32 and the condenser 12 by the traveling wind during traveling. Furthermore, the electric condenser fan 2 is provided adjacent to the radiator 32 and the condenser 12, and the heat radiation from the radiator 32 and the condenser 12 can be forcibly performed by operating the condenser fan 2.

  Furthermore, heat transfer between the vehicle and the vehicle interior air will be described.

  The air conditioning unit that adjusts the temperature in the passenger compartment includes a blower fan 3, an evaporator 14, a mix door 4, and a heater core 35.

  The air selectively taken from the air in the vehicle interior or the outside air by the blower fan 3 is cooled by the evaporator 14, reheated according to the opening degree of the mix door 4, and then from the outlet to the vehicle interior. It is blown out into the room.

  Whether the air taken into the air conditioning unit is the outside air introduction or the inside air circulation is switched according to the opening degree of the intake door provided in the most upstream part of the air conditioning unit. The opening degree of the mix door 4 is set according to a target blowing temperature set based on a set temperature, a detection value of a solar radiation amount sensor, or the like. The blowout ratios of the differential blowout port, vent blowout port, and foot blowout port that are blowout ports into the vehicle interior are adjusted by the opening degree of the differential door, the vent door, and the foot door that adjust the opening degree of each blowout port.

  Further, the sub-radiator 56 can exchange heat between the air in the draft duct 6 and the cooling water in the low water temperature loop 50 when the cabin air is discharged outside the vehicle through the draft duct 6. it can. When the cooling water in the low water temperature loop 50 is lower than the temperature of the passenger compartment air, the sub radiator 56 recovers exhaust heat from the air released to the outside of the vehicle. When the cooling water in the low water temperature loop 50 is higher than the temperature of the cabin air, the sub radiator 56 radiates heat to the air discharged from the cooling water to the outside of the vehicle.

  Next, the controller 70 that controls the operation of the electric vehicle thermal management system 100 will be described with reference to FIG.

  The controller 70 is a detection signal of a charge state sensor 71 that detects that the vehicle is in a charged state, a detection signal of an inside air temperature sensor 72 that detects the temperature of the vehicle interior air, and an outside air temperature sensor 73 that detects the temperature of the vehicle exterior air. Detection signal, a detection signal from a solar radiation sensor 74 for detecting the amount of solar radiation received by the vehicle, a set temperature and an air flow set by the driver operating the A / C controller 75 installed in the instrument panel Setting information, detection signal of the low water temperature loop temperature sensor 76 for detecting the temperature of the cooling water circulating in the low water temperature loop 50, detection signal of the high water temperature loop temperature sensor 77 for detecting the temperature of the cooling water circulating in the high water temperature loop 30 And a detection signal of the refrigerant pressure sensor 78 for detecting the refrigerant pressure of the air conditioner loop 10 is received.

  The controller 70 processes various received signals, and the air volume of the blower fan 3, the opening degree of each door, the rotational speed of the compressor 11, the operation of the condenser fan 2, the operation of the hot water heater 54, the operation of the radiator pump 31, H / C pump 34 operation, battery pump 51 operation, three-way valve 20 switching, water switching valve 37 switching, EVA solenoid valve 22 opening / closing, chiller solenoid valve 23 opening / closing, sub RAD solenoid valve 59 opening / closing, bypass The opening / closing of the electromagnetic valve 58 and the lighting state of the caution lamp 60 are controlled.

  The caution lamp 60 is a warning lamp that notifies the driver that the compressor 11 is abnormal, and is provided, for example, in a combination meter in the passenger compartment.

  Next, processing contents performed by the controller 70 of the electric vehicle thermal management system 100 will be described with reference to FIGS. 4 to 6 are flowcharts showing processing performed by the controller 70 when the vehicle is in a driving state (a state where the driver is on the vehicle). The control processing shown in FIGS. 4 to 6 is repeatedly performed every minute time.

  In step S1, the controller 70 determines whether or not the blower fan 3 is operating. If it is determined that the blower fan 3 is operating, the process proceeds to step S2, and if it is determined that the blower fan 3 is not operating, the process proceeds to step S18 in FIG. The blower fan 3 is determined to be operating when the air conditioning unit of the vehicle is operating, for example, when the driver operates the A / C controller 75 to operate the air conditioning.

  In step S2, the controller 70 calculates a target blowing temperature. The target blowing temperature is calculated based on the set temperature of the air conditioning unit, the air temperature in the vehicle interior, the outside air temperature, the amount of solar radiation received by the vehicle, and the like. For example, when the driver presses the AUTO switch in the A / C controller 75 to set the auto mode, the target blowing temperature is automatically calculated so that the air temperature in the passenger compartment becomes the set temperature.

  In step S3, the controller 70 determines whether there is a heating request. If it is determined that there is a heating request, the process proceeds to step S4. If it is determined that there is no heating request, the process proceeds to step S14. The presence / absence of the heating request is based on the target blowout temperature and the vehicle interior air temperature.For example, when the target blowout temperature is higher than the vehicle interior air temperature, there is a heating request, and when the target blowout temperature is lower than the vehicle interior air temperature. Is judged to have a cooling request.

  In step S4, the controller 70 sets the air conditioning cycle of the air conditioning unit to the heating mode, opens the EVA electromagnetic valve 22, and sets the air conditioning unit (HVAC) to the auto mode. Thereby, the air volume of the blower fan 3 and the door position of each door (intake door, mix door, differential door, vent door, foot door) are automatically controlled so that the vehicle interior temperature becomes the set temperature. Along with this, the condenser fan 2 and the radiator pump 31 are stopped, and the bypass solenoid valve 58 is opened.

  In step S5, the controller 70 determines whether or not the cooling water temperature of the low water temperature loop 50 is 15 ° C. or less. If it is determined that the cooling water temperature is 15 ° C. or lower, the process proceeds to step S6. If it is determined that the cooling water temperature is higher than 15 ° C., the process proceeds to step S7. The threshold value for determination in this step, 15 ° C., is appropriately set to the lower limit value of the temperature preferable for operation based on the specifications of the battery 1.

  In step S6, the controller 70 operates the hot water heater 54.

  In step S7, the controller 70 stops the hot water heater 54.

  In step S8, the controller 70 determines whether or not the cooling water temperature of the low water temperature loop 50 is 35 ° C. or higher. If it is determined that the cooling water temperature is 35 ° C. or higher, the process proceeds to step S10, and if it is determined that the cooling water temperature is lower than 35 ° C., the process proceeds to step S9. 35 ° C., which is the threshold value for the determination in this step, is appropriately set to an upper limit value of temperature preferable for operation based on the specifications of the battery 1.

  In step S9, the controller 70 sets the compressor 11 to the blowout temperature tracking control. The blowout temperature tracking control is control for adjusting the rotation speed of the compressor 11 so that the target blowout temperature becomes a desired temperature in the auto mode of the air conditioning unit set in step S4.

  In step S10, the controller 70 controls the rotation speed of the compressor 11 so that the cooling water temperature of the low water temperature loop 50 becomes 35 ° C.

  That is, in the above steps S8 to S10, when the cooling water temperature of the low water temperature loop 50 is 35 ° C. or higher, the controller 70 determines that the heating capacity is surplus and keeps the cooling water temperature at 35 ° C. The compressor 11 is controlled.

  In step S11, the controller 70 determines whether or not the cooling water temperature of the high water temperature loop 30 is equal to or higher than the water temperature Xm. If it is determined that the cooling water temperature is equal to or higher than the water temperature Xm, the process proceeds to step S12. If it is determined that the cooling water temperature is lower than the water temperature Xm, the process proceeds to step S13. The water temperature Xm is the target blowing temperature calculated in step S2.

  In step S12, the controller 70 uses the high water temperature loop 30 as a radiator circuit to operate the condenser fan 2. The radiator circuit is a circuit in which the cooling water is also circulated to the radiator 32 by driving the radiator pump 31 in addition to the heater core circuit in which the cooling water in the high water temperature loop 30 circulates through the heater core 35. In the radiator circuit, in addition to the heat absorbed by the water condenser 16 being exhausted into the passenger compartment by the heater core 35, the cooling water is exhausted outside the passenger compartment by the radiator 32. That is, when the cooling water temperature of the high water temperature loop 30 becomes equal to or higher than the water temperature Xm, the cooling water of the high water temperature loop 30 is forcibly cooled by radiator radiation.

  In step S13, the controller 70 uses the high water temperature loop 30 as a heater core circuit, and stops the condenser fan 2. The heater core circuit is a circuit in which the cooling water of the high water temperature loop 30 circulates through the heater core 35 and the water condenser 16. In this case, the cooling water of the high water temperature loop 30 is not radiated from the radiator.

  On the other hand, if it is determined in step S3 that there is no heating request, the process proceeds to step S14, where the controller 70 sets the air conditioning cycle of the air conditioning unit to the cooling mode, opens the EVA electromagnetic valve 22, and opens the air conditioning unit ( HVAC) is set to auto mode. Thereby, the air volume of the blower fan 3 and the door position of each door (intake door, mix door, differential door, vent door, foot door) are automatically controlled so that the vehicle interior temperature becomes the set temperature. Along with this, the condenser fan 2 and the radiator pump 31 are operated, and the bypass electromagnetic valve 58 is opened.

  In step S15, the controller 70 determines whether or not the cooling water temperature of the low water temperature loop 50 is 35 ° C. or less. If it is determined that the cooling water temperature is 35 ° C. or lower, the process proceeds to step S16. If it is determined that the cooling water temperature is higher than 35 ° C., the process proceeds to step S17. 35 ° C., which is the threshold value for the determination in this step, is appropriately set to an upper limit value of temperature preferable for operation based on the specifications of the battery 1.

  In step S16, the controller 70 closes the chiller solenoid valve 23 and controls the compressor 11 so that the air temperature immediately after the evaporator 14 in the air conditioning unit becomes 3 ° C. (direct-evaporation 3 ° C. control).

  In step S <b> 17, the controller 70 opens the chiller solenoid valve 23 and controls the compressor 11 so that the air temperature immediately after the evaporator 14 in the air conditioning unit becomes 3 ° C.

  That is, in the cooling mode, the compressor 11 is controlled so that the air temperature immediately after the evaporator 14 becomes 3 ° C. regardless of the battery temperature, and when the cooling water temperature of the low water temperature loop 50 is 35 ° C. or more, the chiller 17 Absorbs heat.

  On the other hand, if it is determined in step S1 that the blower fan 3 is stopped, the process proceeds to step S18 in FIG. 5, and the controller 70 sets the air conditioning cycle of the air conditioning unit to the cooling mode, and sets the EVA electromagnetic valve 22 to the cooling mode. Closed. Along with this, the condenser fan 2 and the radiator pump 31 are operated.

  In step S19, the controller 70 determines whether or not the cooling water temperature of the low water temperature loop 50 is 35 ° C. or higher. If it is determined that the cooling water temperature is 35 ° C. or higher, the process proceeds to step S20. If it is determined that the cooling water temperature is lower than 35 ° C., the process proceeds to step S21.

  In step S <b> 20, the controller 70 opens the chiller solenoid valve 23 and operates the compressor 11. Thereby, the refrigerant of the air conditioner loop 10 flows to the chiller 17 and absorbs heat from the cooling water of the low water temperature loop 50.

  In step S <b> 21, the controller 70 closes the chiller electromagnetic valve 23 and stops the compressor 11. Thereby, the refrigerant | coolant flow of the air-conditioner loop 10 stops.

  That is, even when the air conditioning is off, if the battery temperature is high, the heat is absorbed from the chiller 17 and is radiated from the capacitor 12.

  Moving to FIG. 6, in step S <b> 22, the controller 70 determines whether there is a heating request and the cooling water temperature in the low water temperature loop 50 is lower than the temperature in the passenger compartment. If the condition is satisfied, the process proceeds to step S24. If the condition is not satisfied, the process proceeds to step S23. In this step, it is determined whether or not the electric vehicle thermal management system 100 needs heating heat and the exhaust heat can be recovered from the air discharged from the draft duct 6 to the outside of the vehicle.

  In step S23, the controller 70 opens the bypass electromagnetic valve 58. Thereby, the cooling water of the low water temperature loop 50 circulates around the sub radiator 56.

  In step S24, the controller 70 opens the sub RAD solenoid valve 59. As a result, the cooling water in the low water temperature loop 50 circulates via the sub radiator 56.

  In step S25, the controller 70 determines whether or not the compressor 11 is abnormal. If it is determined that the compressor 11 is abnormal, the process proceeds to step S26. If it is determined that the compressor 11 is not abnormal, the process ends. When the detected value of the refrigerant pressure sensor 78 is equal to or higher than a predetermined upper limit value or lower limit value, the controller 70 indicates that the compressor 11 is abnormal when the outside air temperature sensor 73 is abnormal or when communication with various sensors is abnormal. judge.

  In step S26, the controller 70 forcibly stops the compressor 11. Further, the controller 70 operates the battery pump 51 to open the sub RAD electromagnetic valve 59 and stop the hot water heater 54. Further, the controller 70 sets the fan speed of the blower fan 3 of the air conditioning unit to the maximum speed (Hi), drives the foot door to fully open the foot outlet, and drives the intake door to enter the outside air introduction mode. Further, the controller 70 turns on a caution lamp 60 that notifies the driver of the abnormality of the compressor 11.

  As described above, when the compressor 11 is abnormal, the compressor 11 is forcibly stopped, so that the refrigerant flow in the air conditioner loop 10 stops and heat absorption in the chiller 17 is not performed. Therefore, the cooling water in the low water temperature loop 50 is circulated to the sub radiator 56 and radiated from the sub radiator 56 to the air discharged outside the vehicle, thereby suppressing an increase in the cooling water temperature in the low water temperature loop 50.

  Furthermore, by setting the outside air introduction mode and setting the fan speed of the blower fan 3 to the maximum speed, the amount of air discharged to the outside of the vehicle through the draft duct 6 is maximized, so that the heat radiation from the sub-radiator 56 is further increased. Can be promoted.

  Next, operation | movement of the thermal management system 100 for electric vehicles is demonstrated with reference to FIGS. In each figure, among the circuits of the air conditioner loop 10, the high water temperature loop 30, and the low water temperature loop 50, a portion indicated by a thick line indicates a portion through which refrigerant or cooling water flows.

  FIG. 7 is a circuit diagram showing the operation of the electric vehicle thermal management system 100 during heating.

  In the air conditioner loop 10, the compressor 11 is operated to circulate refrigerant in the order of the three-way valve 20, the water condenser 16, the evaporator electromagnetic valve 22, the expansion valve 13, and the evaporator 14, and in parallel with this, the three-way valve 20, water condenser 16, chiller solenoid valve 23, expansion valve 18, and chiller 17 are circulated in this order. Since the refrigerant circulation path is regulated by the three-way valve 20 and the check valve 21, the refrigerant does not flow to the condenser 12 side.

  In the low water temperature loop 50, the battery pump 51 is operated to circulate the cooling water in the order of the sub RAD electromagnetic valve 59, the sub radiator 56, the DC / DC converter 52, the inverter 53, the hot water heater 54, the water jacket 55, and the chiller 17. . When the temperature of the cooling water in the low water temperature loop 50 is equal to or higher than the temperature in the passenger compartment, the sub RAD electromagnetic valve 59 is closed, the bypass electromagnetic valve 58 is opened, and the cooling water flows to the sub radiator 56. Absent.

  In the high water temperature loop 30, the H / C pump 34 operates to circulate the cooling water in the order of the heater core 35, the water condenser 16, the water switching valve 37, and the motor 33. The cooling water circulation path is regulated by the water switching valve 37, and the cooling water does not flow between the water switching valve 37 and the H / C pump 34 in the bypass flow path 36. Further, since the radiator pump 31 is not operated, the cooling water does not flow to the radiator 32.

  Thus, during heating, in addition to the heat stored in the battery 1 and the heat generated by charging and discharging, the heat loss in the inverter 53 and the DC / DC converter 52, the vehicle that is released outside the vehicle through the draft duct 6 The exhaust heat of the room air is absorbed by the cooling water of the low water temperature loop 50, and the cooling water is heated by the hot water heater 54 as necessary. The heat of the cooling water is transmitted to the refrigerant of the air conditioner loop 10 in the chiller 17.

  Further, in the air conditioner loop 10, heat is transferred from the high-temperature refrigerant on the discharge side of the compressor 11 to the cooling water of the high water temperature loop 30 by the water condenser 16, and the heat of the low water temperature loop 50 is absorbed in the chiller 17. In the high water temperature loop 30, the cooling water heated by the exhaust heat of the water condenser 16 and the motor 33 is circulated to the heater core 35.

  FIG. 8 is a circuit diagram showing the operation of the thermal management system 100 for an electric vehicle during cooling.

  In the air-conditioner loop 10, the compressor 11 is operated to circulate refrigerant in the order of the three-way valve 20, the condenser 12, the check valve 21, the evaporator electromagnetic valve 22, the expansion valve 13, and the evaporator 14, and in parallel with this check valve. The chiller solenoid valve 23, the expansion valve 18, and the chiller 17 are circulated in this order. Since the refrigerant circulation path is regulated by the three-way valve 20, the refrigerant does not flow to the water condenser 16 side.

  In the low water temperature loop 50, the battery pump 51 operates to circulate the cooling water in the order of the bypass solenoid valve 58, the DC / DC converter 52, the inverter 53, the hot water heater 54, the water jacket 55, and the chiller 17.

  In the high water temperature loop 30, the radiator pump 31 operates to circulate the cooling water in the order of the radiator 32 and the motor 33. Since the H / C pump 34 is not operating, the cooling water does not flow through the heater core 35 but circulates between the motor 33 and the radiator 32.

  Thereby, at the time of cooling, the heat stored in the battery 1 and the heat generated due to charging / discharging and the heat loss in the inverter 53 and the DC / DC converter 52 are absorbed into the cooling water of the low water temperature loop 50. The excess heat from the cooling water is transmitted to the refrigerant in the air conditioner loop 10 in the chiller 17.

  Further, in the air conditioner loop 10, the evaporator 14 absorbs heat from the air supplied to the vehicle interior, the chiller 17 absorbs excess heat of the low water temperature loop 50, and the condenser 12 radiates heat from the refrigerant to the outside air. In the high water temperature loop 30, the exhaust heat of the motor 33 is released by the radiator 32.

  FIG. 9 is a circuit diagram illustrating the operation of the electric vehicle thermal management system 100 when the compressor is abnormal.

  When it is determined that the compressor 11 is abnormal during cooling and the compressor 11 is forcibly stopped, the refrigerant flow in the air conditioner loop 10 is stopped. Thereby, the heat absorption from the low water temperature loop 50 in the chiller 17 is stopped.

  In the high water temperature loop 30, heat transfer with the air conditioner loop 10 is not performed, so even if the compressor 11 is stopped, the cooling water temperature of the high water temperature loop 50 is not affected.

  However, in the low water temperature loop 50, the heat absorption in the chiller 17 stops, so that the coolant temperature rises due to the exhaust heat of the battery 1, the inverter 53, and the DC / DC converter 52. Therefore, the bypass electromagnetic valve 58 is closed, the sub RAD electromagnetic valve 59 is opened, and the flow path is switched so that the cooling water flows to the sub radiator 56. Furthermore, outside air is introduced with the maximum air volume by the air conditioning unit, and the amount of air released from the draft duct 6 is increased. Thereby, since heat can be radiated from the sub radiator 56 to the air in the draft duct 6, the rising speed of the cooling water temperature can be suppressed.

  As described above, in this embodiment, when it is determined that the compressor 11 is abnormal and the compressor 11 is forcibly stopped, the sub RAD electromagnetic valve 59 is opened and the cooling water in the low water temperature loop 50 is sub Since it is circulated to the radiator 56, the heat of the cooling water in the low water temperature loop 50 can be radiated from the sub radiator 56 to the air in the draft duct 6. Thereby, even if the refrigerant circulation of the air-conditioner loop 10 is stopped when the compressor 11 is abnormal and the heat dissipation from the low-temperature refrigerant in the chiller 17 is stopped, an increase in the cooling water temperature of the low water temperature loop 50 can be suppressed. Therefore, even if the compressor 11 breaks down, the increase in battery temperature can be suppressed and the vehicle can continue to travel longer.

  When there is a heating request and the cooling water temperature in the low water temperature loop 50 is lower than the cabin temperature, the sub RAD electromagnetic valve 59 is opened, and the cooling water in the low water temperature loop 50 is passed to the sub radiator 56. Since it is circulated, it is possible to cause the cooling water to absorb the exhaust heat of the air that is released outside the passenger compartment through the draft duct 6. As a result, the amount of heat that can be recovered as a whole system during heating increases, and the amount of exhaust heat used increases. Therefore, the frequency of using the compressor 11 and the hot water heater 54 decreases, and the decrease in the cruising range of the vehicle can be suppressed. it can.

  The embodiment of the present invention has been described above, but the above embodiment shows an application example of the present invention, and is not intended to limit the technical scope of the present invention to the specific configuration of the above embodiment.

  For example, in the above-described embodiment, the cooling water temperature threshold of the low water temperature loop 50 for determining the operation of the hot water heater 54 is set to 15 ° C., but other ranges are suitable for the operating temperature of the battery 1 provided in the low water temperature loop 50. The temperature may be set to

  Furthermore, although the threshold value of the cooling water temperature of the low water temperature loop 50 for determining the control switching of the compressor 11 is set to 35 ° C., the operating temperature of the battery 1 provided in the low water temperature loop 50 is set to another temperature within an appropriate range. May be.

  Furthermore, although the threshold value of the cooling water temperature of the low water temperature loop 50 for determining whether the chiller solenoid valve 23 is opened or closed is set to 35 ° C., the operating temperature of the battery 1 provided in the low water temperature loop 50 is set to another temperature within an appropriate range. May be.

  Further, the thresholds of 15 ° C. and 35 ° C. may be provided with a differential (hysteresis) to prevent chattering, and may be set to different temperatures when the water temperature rises and falls.

  Furthermore, although the cooling water of the low water temperature loop 50 and the high water temperature loop 30 has been described by taking an antifreeze liquid as an example, other refrigerants such as oil may be used.

1 Battery 6 Draft duct (drafter)
10 Air conditioner cycle (refrigerant loop for air conditioner)
11 Compressor (compression unit)
12 condenser (condensing part)
13 Expansion valve (pressure reduction part)
14 Evaporator
16 Water condenser (condensing part)
17 Chiller (evaporation part)
30 High water temperature loop (refrigerant loop for heater)
35 Heater core (in-vehicle radiator)
50 Low water temperature loop (battery refrigerant loop)
56 Sub-radiator (heat exchanger)
58 Bypass solenoid valve (switching means)
59 Sub RAD solenoid valve (switching means)
70 Controller (thermal management control means)
100 Thermal management system for electric vehicles

Claims (2)

A vehicle thermal management system used for an electric vehicle driven by an electric motor,
A compressor that compresses the air conditioner refrigerant, a condensing unit that dissipates heat from the air conditioner refrigerant to condense the air conditioner refrigerant, a decompression unit that expands and decompresses the air conditioner refrigerant, and an air conditioner refrigerant that absorbs heat. An air-conditioning refrigerant loop for circulating the air-conditioning refrigerant,
The battery refrigerant is provided in a battery that stores electric power supplied to the electric motor, the evaporator common to the air-conditioner refrigerant loop, and a ventilation drafter that discharges air in the passenger compartment to the outside of the passenger compartment. A heat exchanger for exchanging heat between the air flowing through the drafter and the battery refrigerant, and a battery refrigerant loop circulated between the heat exchanger and the battery refrigerant;
Switching means switchable between a state in which the battery refrigerant loop flows through the heat exchanger and a state in which the heat exchanger is bypassed;
When the compressor cannot compress the air conditioner refrigerant, the battery refrigerant loop is switched to the state of flowing through the heat exchanger, and the heat exchanger transfers the heat of the battery refrigerant to the air in the drafter. And heat management control means for radiating heat,
The thermal management system for electric vehicles characterized by comprising. The heat management system for an electric vehicle according to claim 1,
A heater refrigerant loop that circulates the refrigerant for the heater between the condensing part in common with the refrigerant loop for the air conditioner and an in-vehicle radiator that radiates heat from the heater refrigerant to the air introduced into the vehicle;
In the case where the target blowout temperature of the air conditioning unit for adjusting the vehicle interior temperature is higher than the vehicle interior air temperature and the temperature of the battery coolant is lower than the vehicle interior air temperature, the thermal management control means Is switched to a state in which the heat exchanger flows, and the battery refrigerant absorbs heat from the air flowing in the draft by the heat exchanger.
The thermal management system for electric vehicles characterized by the above-mentioned.

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