WO2019049636A1 - Vehicular air conditioning device - Google Patents

Abstract

Provided is a vehicular air conditioning device that can preemptively avoid unnecessary defrosting of an outside heat exchanger. A refrigerant discharged from a compressor 2 is made to release heat in a radiator 4, and, after the refrigerant that has released heat has been decompressed, a heating mode is executed in which the interior of a vehicle is heated by causing heat to be absorbed by an outside heat exchanger 7. A control device determines the state of progress of frost formation on the outside heat exchanger, and if defrosting has been determined to be unnecessary, causes defrosting to be performed on the outside heat exchanger once prescribed defrosting permission conditions have been met; and if prescribed natural defrosting conditions are met before defrosting is performed after defrosting of the outside heat exchanger has been determined to be necessary, the control device does not cause defrosting to be performed on the outside heat exchanger.

Description

Vehicle air conditioner

The present invention relates to a heat pump type air conditioner for air conditioning a vehicle cabin of a vehicle.

The recent emergence of environmental problems has led to the spread of hybrid vehicles and electric vehicles. And, as an air conditioner which can be applied to such a vehicle, a compressor which compresses and discharges a refrigerant, a radiator which is provided on the vehicle interior side and which radiates the refrigerant, and which is provided outside a vehicle interior An outdoor heat exchanger for absorbing heat of the refrigerant is provided, the refrigerant discharged from the compressor is dissipated by the radiator, and the refrigerant dissipated by the radiator is absorbed by the outdoor heat exchanger, thereby heating the vehicle interior by heating mode. What has been developed has been developed (see, for example, Patent Document 1 and Patent Document 2).

JP, 2015-39998, A JP, 2015-229370, A

Here, in the heating mode, the refrigerant evaporates in the outdoor heat exchanger and absorbs heat from the outside air, so frost formation occurs on the outdoor heat exchanger. If the operation of the compressor is continued in a state where frost formation on the outdoor heat exchanger has progressed, the heat absorption capacity from the outside air is reduced, so that the operation efficiency is significantly reduced. Therefore, it is necessary to stop the heating mode and perform defrosting of the outdoor heat exchanger, but in that case heating of the vehicle interior can not be performed, and the comfort of the driver and the passenger is impaired. For example, there is no air conditioning requirement, and defrosting of the outdoor heat exchanger is performed under conditions where defrosting is permitted during charging of the battery.
On the other hand, the frost formed on the outdoor heat exchanger melts naturally with the passage of time if the outside air temperature rises. Further, in the operation mode other than the heating mode (for example, the cooling mode or the dehumidifying mode), the outdoor heat exchanger serves as a radiator that radiates the refrigerant, so that the frost is melted and removed. In such a case, it is not necessary to defrost the outdoor heat exchanger, but conventionally, once it is determined that defrosting of the outdoor heat exchanger is necessary, it is always required that defrosting be permitted. Defrosting was taking place.
The present invention has been made to solve such conventional technical problems, and an air conditioner for a vehicle that can prevent unnecessary defrosting of the outdoor heat exchanger from occurring. Intended to be provided.

The air conditioner for a vehicle according to the present invention heats the air supplied from the air flow passage to the vehicle compartment from the air flow passage by radiating the refrigerant and the air flow passage through which the air supplied to the vehicle is circulated. A radiator, an outdoor heat exchanger provided outside the vehicle compartment for absorbing heat, and a control device, the control device causing the radiator to dissipate at least the refrigerant discharged from the compressor After decompressing the refrigerant that has dissipated the heat, the heating mode is performed by heating the vehicle interior by absorbing heat with the outdoor heat exchanger, and the control device determines the progress of frost formation on the outdoor heat exchanger When it was determined that it was determined that defrosting was necessary, the outdoor heat exchanger was defrosted and it was determined that defrosting of the outdoor heat exchanger was necessary when a predetermined defrost permission condition was satisfied. After that, a predetermined natural defrosting condition is satisfied before defrosting The, characterized in that it does not perform the defrosting of the outdoor heat exchanger.
The air conditioning apparatus for a vehicle according to the invention of claim 2 is characterized in that the natural defrosting condition in the invention is:
The outside air temperature Tam is equal to or higher than a predetermined value Tam1, and the refrigerant evaporation temperature TXO of the outdoor heat exchanger is equal to or higher than an outside air temperature Tam-predetermined value β.
The integrated value of the time during which the outside air temperature Tam is equal to or higher than the predetermined value Tam2 is equal to or longer than a predetermined time t3 while the vehicle is stopped.
During the stop of the vehicle, the outside air temperature Tam becomes equal to or higher than the predetermined value Tam2, and the integral value obtained from the difference and the elapsed time becomes equal to or higher than the predetermined value X1.
A predetermined period t4 or more has elapsed since the vehicle stopped.
The operation mode not to absorb the refrigerant is selected by the outdoor heat exchanger,
Or any combination thereof, or all of them.
The vehicle air conditioner of the invention of claim 3 is characterized in that, in each of the inventions described above, the control device causes the refrigerant evaporation temperature TXO of the outdoor heat exchanger to fall below the refrigerant evaporation temperature TXObase of the outdoor heat exchanger at the time of no frost formation. The difference between the refrigerant evaporation temperature TXO of the outdoor heat exchanger and the refrigerant evaporation temperature TXObase of the outdoor heat exchanger at the time of no frost, based on .DELTA.TXO = TXObase-TXO, or the refrigerant evaporation pressure PXO of the outdoor heat exchanger is not adhered The difference ΔPXO between the refrigerant evaporation pressure PXO of the outdoor heat exchanger and the refrigerant evaporation pressure PXObase of the outdoor heat exchanger at the time of no frost when the temperature is lower than the refrigerant evaporation pressure PXObase of the outdoor heat exchanger at the time of frost ΔPXO = PXObase−PXO The present invention is characterized in that the progress of frost formation on the outdoor heat exchanger is determined on the basis of.
In the vehicle air conditioner of the invention of claim 4, in the above invention, the control device is the refrigerant evaporation temperature TXObase of the outdoor heat exchanger at the time of frost-free based on the environmental condition and / or the index indicating the driving condition. Alternatively, the refrigerant evaporation pressure PXObase of the outdoor heat exchanger at the time of no frost formation is estimated.
In the vehicle air conditioner of the invention of claim 5, in each of the inventions described above, the compressor is driven by the battery mounted on the vehicle, and the defrost permission condition does not require air conditioning of the vehicle interior, and the battery Is that the battery is being charged or the remaining amount of the battery is equal to or more than a predetermined value.
In the vehicle air conditioner according to the invention of claim 6, according to each of the inventions described above, the control device is an air conditioning controller to which an air conditioning operation unit for performing an air conditioning setting operation in the vehicle compartment is connected, and a heat pump for controlling the operation of the compressor. The air conditioning controller and the heat pump controller transmit and receive information via the vehicle communication bus, and the heat pump controller determines that the outdoor heat exchanger needs to be defrosted, and the predetermined defrost request flag is set. When the air conditioning controller sets a predetermined defrost permission flag, the outdoor heat exchanger is defrosted, the defrost request flag is reset, and the defrost request flag is set, and then the natural defrost condition is set. Even when the above condition is established, the defrost request flag is reset, and the air conditioning controller causes the heat pump controller to defrost the request flag. If set, it determines whether defrost permission condition is satisfied, when filled, characterized in that setting the defrost permission flag.
In the air conditioner for a vehicle according to the invention of claim 7, when the air conditioning controller or the heat pump controller determines whether the natural defrosting condition holds in the above invention, natural defrosting is performed when the air conditioning controller determines. The heat pump controller is notified that the condition is satisfied.

According to the present invention, the compressor for compressing the refrigerant, the air flow passage through which the air supplied to the vehicle compartment flows, and the radiator for radiating the heat of the refrigerant and heating the air supplied from the air flow passage to the vehicle compartment And an outdoor heat exchanger provided outside the vehicle for absorbing heat of the refrigerant, and a control device, wherein the control device causes at least the refrigerant discharged from the compressor to be dissipated by the radiator and dissipated In a vehicle air conditioner that executes a heating mode of heating the vehicle interior by absorbing heat with the outdoor heat exchanger after depressurizing the refrigerant, the control device determines the progress of frost formation on the outdoor heat exchanger. When it is determined that defrosting is necessary, the outdoor heat exchanger is defrosted when it is determined that the predetermined defrost permission condition is satisfied, and after it is determined that defrosting of the outdoor heat exchanger is necessary, A place where a predetermined natural defrosting condition is established before defrosting In order to prevent defrosting of the outdoor heat exchanger, even if it is determined that defrosting of the outdoor heat exchanger is necessary, then a predetermined natural defrosting condition is satisfied and the outdoor heat exchanger is When frost formation is expected to be naturally melted, unnecessary defrosting of the outdoor heat exchanger can be avoided in advance without defrosting.
By this, without performing defrosting of the outdoor heat exchanger, defrosting is not performed in a situation where heating of the vehicle interior can be performed, and comfortable heating and air conditioning of the vehicle interior can be realized while contributing to energy saving. Will be able to
In this case, natural defrosting conditions as in the invention of claim 2 are
The outside air temperature Tam is equal to or higher than a predetermined value Tam1, and the refrigerant evaporation temperature TXO of the outdoor heat exchanger is equal to or higher than an outside air temperature Tam-predetermined value β.
The integrated value of the time during which the outside air temperature Tam is equal to or higher than the predetermined value Tam2 is equal to or longer than a predetermined time t3 while the vehicle is stopped.
During the stop of the vehicle, the outside air temperature Tam becomes equal to or higher than the predetermined value Tam2, and the integral value obtained from the difference and the elapsed time becomes equal to or higher than the predetermined value X1.
A predetermined period t4 or more has elapsed since the vehicle stopped.
The operation mode not to absorb the refrigerant is selected by the outdoor heat exchanger,
By combining any or all of them, it is possible to properly predict that the frost formation on the outdoor heat exchanger has naturally melted.
Further, as in the invention of claim 3, the control device controls the refrigerant evaporation of the outdoor heat exchanger when the refrigerant evaporation temperature TXO of the outdoor heat exchanger is lower than the refrigerant evaporation temperature TXObase of the outdoor heat exchanger when frost does not occur. The outdoor heat exchanger based on the difference ΔTXO = TXObase-TXO between the temperature TXO and the refrigerant evaporation temperature TXObase of the outdoor heat exchanger at the time of no frost, or when the refrigerant evaporation pressure PXO of the outdoor heat exchanger is at no frost This outdoor heat exchanger is based on the difference ΔPXO = PXObase−PXO between the refrigerant evaporation pressure PXO of the outdoor heat exchanger and the refrigerant evaporation pressure PXObase of the outdoor heat exchanger at the time of no frost when the refrigerant evaporation pressure PXObase falls below By determining the progress of frost formation on the outdoor heat exchanger, it is possible to accurately grasp the progress of frost formation on the outdoor heat exchanger and correct the necessity of defrosting. You will be able to make a decision.
In this case, as in the invention of claim 4, the control device controls the refrigerant evaporation temperature TXObase of the outdoor heat exchanger at the time of non-frosting based on the environmental condition and / or the index indicating the operating condition or at the time of non-frosting By estimating the refrigerant evaporation pressure PKObase of the outdoor heat exchanger in the above, it is possible to accurately detect the progress of frost formation on the outdoor heat exchanger.
In the defrosting permission condition, for example, there is no air conditioning requirement for the vehicle interior as in the invention of claim 5, and the battery for driving the compressor is charging or the remaining amount of the battery is a predetermined value or more It should be a certain thing.
According to the invention of claim 6, the control device comprises an air conditioning controller connected to an air conditioning operation unit for performing an air conditioning setting operation in the vehicle compartment, and a heat pump controller for controlling the operation of the compressor. When the heat pump controller transmits and receives information via the vehicle communication bus, the heat pump controller sets a predetermined defrost request flag when it is determined that defrosting of the outdoor heat exchanger is necessary, and the air conditioning controller When the predetermined defrost permission flag is set, the outdoor heat exchanger is defrosted, the defrost request flag is reset, and the defrost request flag is set, and then the natural defrost condition is satisfied. Also, if the defrost request flag is reset and the air conditioning controller has the defrost request flag set by the heat pump controller It is determined whether the defrosting permission condition is satisfied, and if satisfied, the defrosting permission flag is set to comfortably heat and air the vehicle interior, and further, the arrival of the outdoor heat exchanger Unnecessary defrosting can be avoided while appropriately suppressing the decrease in the operating efficiency caused by the frost.
In the above case, the air conditioning controller or the heat pump controller may determine whether or not the natural defrosting condition is satisfied as in the invention of claim 7, and if the air conditioning controller determines that By notifying the heat pump controller that the frost condition is established, it is possible to avoid unnecessary defrosting of the outdoor heat exchanger without any trouble.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram of the air conditioning apparatus for vehicles of one Embodiment to which this invention is applied (Example 1). It is a block diagram of the control apparatus of the air conditioning apparatus for vehicles of FIG. It is a schematic diagram of the airflow path of the air conditioning apparatus for vehicles of FIG. It is a control block diagram regarding compressor control in heating mode of the heat pump controller of FIG. It is a control block diagram regarding compressor control in the dehumidification heating mode of the heat pump controller of FIG. It is a control block diagram regarding the auxiliary heater (auxiliary heating device) control in the dehumidification heating mode of the heat pump controller of FIG. It is a flowchart explaining the operation | movement of the part of frost formation determination control of the outdoor heat exchanger by the heat pump controller of FIG. It is a flowchart explaining the operation | movement of the part of natural defrost determination control of the outdoor heat exchanger by the heat pump controller of FIG. It is a timing chart explaining frost formation judgment of the outdoor heat exchanger by the heat pump controller of FIG. 2 based on TXObase and TXO. It is a timing chart explaining frost formation judgment of the outdoor heat exchanger by the heat pump controller of FIG. 2 based on PXObase and PKO. It is a figure explaining an example of the 3rd natural defrosting conditions in natural defrost determination control of FIG. It is a figure explaining an example of the 4th natural defrost conditions in natural defrost determination control of FIG. It is a block diagram of the air conditioning apparatus for vehicles of the other Example of this invention (Example 2).

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 shows a configuration diagram of a vehicle air conditioner 1 according to an embodiment of the present invention. The vehicle according to the embodiment to which the present invention is applied is an electric vehicle (EV) in which an engine (internal combustion engine) is not mounted, and is used for traveling with electric power charged in a battery 75 (FIG. 2) mounted in the vehicle. The electric motor is driven to travel (not shown), and the vehicle air conditioner 1 of the present invention is also driven by the power of the battery 75.
That is, the vehicle air conditioner 1 of the embodiment performs a heating mode by heat pump operation using a refrigerant circuit in an electric vehicle that can not be heated by engine waste heat, and further performs a dehumidifying heating mode, a dehumidifying cooling mode, a cooling mode, Each operation mode of the MAX cooling mode (maximum cooling mode) and the auxiliary heater only mode is selectively executed.
The present invention is applicable not only to electric vehicles as vehicles, but also to so-called hybrid vehicles that use an engine and an electric motor for traveling, and is also applicable to ordinary vehicles traveling with an engine. Needless to say.
The vehicle air conditioner 1 of the embodiment performs air conditioning (heating, cooling, dehumidifying, and ventilating) of a vehicle compartment of an electric vehicle, and is an electric type that receives power from a battery 75 to drive and compress a refrigerant. The compressor 2 and the air flow passage 3 of the HVAC unit 10 through which air in the passenger compartment is aerated and circulated, and the high-temperature and high-pressure refrigerant discharged from the compressor 2 flows in through the refrigerant pipe 13G. And an outdoor expansion valve 6 (pressure reducing device) including a motor-operated valve for decompressing and expanding the refrigerant during heating, and a radiator 4 provided outside the vehicle for radiating heat during cooling The outdoor heat exchanger 7, which functions as a heat exchanger and performs heat exchange between the refrigerant and the outside air so as to function as an evaporator during heating, and an indoor expansion valve 8 (pressure reduction device) including a motorized valve that decompresses and expands the refrigerant. , In the air flow passage 3 A heat sink 9 for cooling the air which absorbs heat from the outside of the vehicle interior by absorbing heat from the outside of the vehicle interior during cooling and dehumidification, the accumulator 12 and the like are sequentially connected by the refrigerant pipe 13, and the refrigerant circuit R is It is configured.
The refrigerant circuit R is filled with a predetermined amount of refrigerant and lubricating oil. The outdoor heat exchanger 7 is provided with an outdoor fan 15. The outdoor fan 15 exchanges heat between the outdoor air and the refrigerant by forcibly ventilating the outdoor air to the outdoor heat exchanger 7, whereby the outdoor fan 15 is also outdoors when the vehicle is stopped (that is, the vehicle speed is 0 km / h). The heat exchanger 7 is configured to ventilate outside air.
In addition, the outdoor heat exchanger 7 sequentially has the receiver dryer portion 14 and the subcooling portion 16 on the refrigerant downstream side, and the refrigerant pipe 13A that has come out of the outdoor heat exchanger 7 is a receiver via the solenoid valve 17 opened during cooling. The refrigerant pipe 13B connected to the dryer unit 14 and at the outlet side of the subcooling unit 16 is connected to the inlet side of the heat absorber 9 via the indoor expansion valve 8. The receiver dryer portion 14 and the subcooling portion 16 structurally constitute a part of the outdoor heat exchanger 7.
Further, the refrigerant pipe 13B between the supercooling unit 16 and the indoor expansion valve 8 is provided in heat exchange relation with the refrigerant pipe 13C on the outlet side of the heat absorber 9, and both constitute an internal heat exchanger 19. Thus, the refrigerant flowing into the indoor expansion valve 8 through the refrigerant pipe 13B is cooled (supercooled) by the low temperature refrigerant that has exited the heat absorber 9.
Further, the refrigerant pipe 13A that has exited from the outdoor heat exchanger 7 is branched into the refrigerant pipe 13D, and the branched refrigerant pipe 13D is downstream of the internal heat exchanger 19 via the solenoid valve 21 opened during heating. It is connected in communication with the refrigerant pipe 13C in The refrigerant pipe 13C is connected to the accumulator 12, and the accumulator 12 is connected to the refrigerant suction side of the compressor 2. Further, the refrigerant pipe 13E on the outlet side of the radiator 4 is connected to the inlet side of the outdoor heat exchanger 7 via the outdoor expansion valve 6.
Further, the refrigerant pipe 13G between the discharge side of the compressor 2 and the inlet side of the radiator 4 is provided with a solenoid valve 30 (constituting a flow path switching device) closed during dehumidifying heating and MAX cooling described later. There is. In this case, the refrigerant pipe 13G is branched to a bypass pipe 35 on the upstream side of the solenoid valve 30, and the bypass pipe 35 is a solenoid valve 40 (also constituting a flow path switching device) opened during dehumidifying heating and MAX cooling. Is connected to the refrigerant pipe 13E on the downstream side of the outdoor expansion valve 6). The bypass pipe 45, the solenoid valve 30, and the solenoid valve 40 constitute a bypass device 45.
By configuring the bypass device 45 with the bypass pipe 35, the solenoid valve 30, and the solenoid valve 40 as described later, the dehumidifying heating mode or MAX for directly flowing the refrigerant discharged from the compressor 2 into the outdoor heat exchanger 7 as described later It is possible to smoothly switch between the cooling mode and the heating mode, the dehumidifying cooling mode, and the cooling mode in which the refrigerant discharged from the compressor 2 flows into the radiator 4.
Further, in the air flow passage 3 on the air upstream side of the heat absorber 9, suction ports for the outside air suction port and the inside air suction port are formed (represented by the suction port 25 in FIG. 1), this suction port A suction switching damper 26 is provided at 25 for switching the air introduced into the air flow passage 3 between the inside air (inside air circulation mode) that is the air inside the vehicle compartment and the outside air (outside air introduction mode) that is the air outside the vehicle outside There is. Further, on the air downstream side of the suction switching damper 26, an indoor blower (blower fan) 27 for supplying the introduced internal air and the external air to the air flow passage 3 is provided.
Further, in FIG. 1, reference numeral 23 denotes an auxiliary heater as an auxiliary heating device provided in the vehicle air conditioner 1 of the embodiment. The auxiliary heater 23 of the embodiment is constituted by a PTC heater which is an electric heater, and the inside of the air flow passage 3 which is on the windward side (air upstream side) of the radiator 4 with respect to the air flow of the air flow passage 3. Provided in Then, when the auxiliary heater 23 is energized to generate heat, the air in the air flow passage 3 flowing into the radiator 4 through the heat absorber 9 is heated. That is, the auxiliary heater 23 serves as a so-called heater core to heat the vehicle interior or supplement it.
Here, the air flow passage 3 on the downwind side (air downstream side) of the heat absorber 9 of the HVAC unit 10 is partitioned by the partition wall 10A, and a heating heat exchange passage 3A and a bypass passage 3B bypassing it are formed. The radiator 4 and the auxiliary heater 23 described above are disposed in the heating heat exchange passage 3A.
In the air flow passage 3 on the windward side of the auxiliary heater 23, the air (internal air and outside air) in the air flow passage 3 after flowing into the air flow passage 3 and passing through the heat absorber 9 is assisted. An air mix damper 28 is provided to adjust the ratio of ventilation to the heating heat exchange passage 3A in which the heater 23 and the radiator 4 are disposed.
Furthermore, the HVAC unit 10 on the downwind side of the radiator 4 has a FOOT (foot) outlet 29A (first outlet) and a VENT (vent) outlet 29B (second outlet for the FOOT outlet 29A). An outlet, a first outlet for the DEF outlet 29C, and an outlet for the DEF (def) outlet 29C (second outlet) are formed. The FOOT blowout port 29A is a blowout port for blowing air under the foot of the vehicle compartment and is at the lowest position. Further, the VENT outlet 29B is an outlet for blowing air around the driver's chest and face in the vehicle compartment, and is above the FOOT outlet 29A. The DEF outlet 29C is a outlet for blowing air to the inner surface of the windshield of the vehicle, and is located at the highest position above the other outlets 29A and 29B.
The FOOT outlet 29A, the VENT outlet 29B, and the DEF outlet 29C are respectively provided with a FOOT outlet damper 31A, a VENT outlet damper 31B, and a DEF outlet damper 31C for controlling the amount of air blown out. It is done.
Next, FIG. 2 shows a block diagram of the control device 11 of the vehicle air conditioner 1 of the embodiment. The control device 11 is composed of an air conditioning controller 20 and a heat pump controller 32, each of which is constituted by a microcomputer which is an example of a computer having a processor, and these are CAN (Controller Area Network) and LIN (Local Interconnect Network). Are connected to a vehicle communication bus 65 that constitutes the The compressor 2 and the auxiliary heater 23 are also connected to the vehicle communication bus 65, and the air conditioning controller 20, the heat pump controller 32, the compressor 2 and the auxiliary heater 23 transmit and receive data via the vehicle communication bus 65. It is done.
The air conditioning controller 20 is a higher-level controller that controls the air conditioning inside the vehicle, and the outside air temperature sensor 33 for detecting the outside air temperature Tam of the vehicle and the outside air humidity for detecting the outside air humidity are input to the air conditioning controller 20. A sensor 34, an HVAC suction temperature sensor 36 for detecting the temperature of the air (suctioned air temperature Tas) sucked into the air flow passage 3 from the suction port 25 and flowing into the heat absorber 9, the temperature of the air (internal air) in the vehicle compartment An indoor air temperature sensor 37 for detecting (the indoor temperature Tin), an indoor air humidity sensor 38 for detecting the humidity of the air in the vehicle compartment, and an indoor CO for detecting the carbon dioxide concentration in the vehicle interior ₂ A concentration sensor 39, an outlet temperature sensor 41 for detecting the temperature of the air blown into the vehicle compartment, a discharge pressure sensor 42 for detecting the discharge refrigerant pressure Pd of the compressor 2, and an amount of solar radiation into the vehicle compartment For example, each output of the photosensor type solar radiation sensor 51, the output of the vehicle speed sensor 52 for detecting the moving speed (vehicle speed) of the vehicle, and the air conditioning setting operation of the vehicle interior such as switching of the set temperature and the operation mode. An air conditioning operation unit (air conditioning operation unit) 53 is connected.
In addition, the outdoor air blower 15, the indoor air blower (blower fan) 27, the suction switching damper 26, the air mix damper 28, and the air outlet dampers 31A to 31C are connected to the output of the air conditioning controller 20, and they are used for air conditioning It is controlled by the controller 20. The battery 75 incorporates a controller, and the controller of the battery 75 transmits and receives data to and from the air conditioning controller 20 via the vehicle communication bus 65. Whether the battery 75 is charging the air conditioning controller 20 or not Information and information on the remaining amount (charging amount) of the battery 75 are transmitted.
The heat pump controller 32 mainly controls the control of the refrigerant circuit R, and an input of the heat pump controller 32 is a discharge temperature sensor 43 for detecting a discharge refrigerant temperature Td of the compressor 2 and a suction refrigerant of the compressor 2 A suction pressure sensor 44 for detecting a pressure Ps, a suction temperature sensor 55 for detecting a suction refrigerant temperature Ts of the compressor 2, and a radiator temperature sensor 46 for detecting a refrigerant temperature (a radiator temperature TCI) of the radiator 4; A radiator pressure sensor 47 that detects the refrigerant pressure of the radiator 4 (radiator pressure PCI), a heat sink temperature sensor 48 that detects the refrigerant temperature (heat sink temperature Te) of the heat sink 9, and a refrigerant pressure of the heat sink 9 Heat sensor pressure sensor 49 for detecting the temperature, the auxiliary heater temperature sensor 50 for detecting the temperature of the auxiliary heater 23 (auxiliary heater temperature Tptc), and the outlet of the outdoor heat exchanger 7 The outdoor heat exchanger temperature sensor 54 for detecting the refrigerant temperature (refrigerant evaporation temperature TXO of the outdoor heat exchanger 7, the outdoor heat exchanger temperature TXO), and the refrigerant pressure at the outlet of the outdoor heat exchanger 7 (of the outdoor heat exchanger 7 The outputs of the outdoor heat exchanger pressure sensor 56 for detecting the refrigerant evaporation pressure PKO and the outdoor heat exchanger pressure PKO) are connected.
The heat pump controller 32 outputs the outdoor expansion valve 6, the indoor expansion valve 8, the solenoid valve 30 (for reheating), the solenoid valve 17 (for cooling), the solenoid valve 21 (for heating), the solenoid valve 40 (bypass) ) Are connected, and they are controlled by the heat pump controller 32. The compressor 2 and the auxiliary heater 23 each have a built-in controller, and the controller of the compressor 2 and the auxiliary heater 23 transmits / receives data to / from the heat pump controller 32 via the vehicle communication bus 65. It is controlled.
The heat pump controller 32 and the air conditioning controller 20 mutually transmit and receive data via the vehicle communication bus 65, and control each device based on the output of each sensor and the setting inputted by the air conditioning operation unit 53. In the embodiment in this case, the output of the outside air temperature sensor 33, the output of the discharge pressure sensor 42, the outputs of the vehicle speed sensor 52, the volumetric air flow rate Ga of the air flowing into the air flow passage 3 (calculated by the air conditioning controller 20), the air mix The air volume ratio SW (calculated by the air conditioning controller 20) by the damper 28, the output of the air conditioning operation unit 53 is transmitted from the air conditioning controller 20 to the heat pump controller 32 via the vehicle communication bus 65, and provided for control by the heat pump controller 32 It is done.
Next, the operation of the vehicle air conditioner 1 of the embodiment having the above configuration will be described. In this embodiment, the control device 11 (the air conditioning controller 20 and the heat pump controller 32) operates the heating mode, the dehumidifying heating mode, the dehumidifying cooling mode, the cooling mode, the MAX cooling mode (maximum cooling mode) and the auxiliary heater sole mode. Switch and execute. First, an outline of the flow and control of the refrigerant in each operation mode will be described.
(1) Heating mode
When the heating mode is selected by the heat pump controller 32 (automatic mode) or by the manual air conditioning setting operation (manual mode) to the air conditioning operation unit 53, the heat pump controller 32 opens the solenoid valve 21 (for heating) to open the solenoid valve. Close 17 (for cooling). Also, the solenoid valve 30 (for reheating) is opened, and the solenoid valve 40 (for bypass) is closed. Then, the compressor 2 is operated. The air conditioning controller 20 operates the blowers 15 and 27, and the air mix damper 28 is basically blown out from the indoor blower 27 and passes through the heat absorber 9 and all the air in the air flow passage 3 is heated by the heat exchange passage 3A. In the state of ventilating to the auxiliary heater 23 and the radiator 4, the air volume may be adjusted.
As a result, the high temperature and high pressure gas refrigerant discharged from the compressor 2 passes through the solenoid valve 30 and flows into the radiator 4 from the refrigerant pipe 13G. Since the air in the air flow passage 3 is ventilated to the radiator 4, the air in the air flow passage 3 is a high temperature refrigerant in the heat radiator 4 (when the auxiliary heater 23 is operated, the auxiliary heater 23 and the radiator 4 are While the refrigerant in the radiator 4 loses its heat by air, is cooled, and condenses and liquefies.
The refrigerant liquefied in the radiator 4 exits the radiator 4 and then reaches the outdoor expansion valve 6 through the refrigerant pipe 13E. The refrigerant flowing into the outdoor expansion valve 6 is decompressed there, and then flows into the outdoor heat exchanger 7. The refrigerant flowing into the outdoor heat exchanger 7 evaporates, and heat is pumped up from the outside air ventilated by the traveling or the outdoor blower 15. That is, the refrigerant circuit R is a heat pump. Then, the low temperature refrigerant leaving the outdoor heat exchanger 7 passes through the refrigerant piping 13A, the solenoid valve 21 and the refrigerant piping 13D, enters the accumulator 12 from the refrigerant piping 13C, and is separated into gas and liquid there, and then the gas refrigerant is the compressor 2 Repeat the cycle of sucking in Since the air heated by the radiator 4 (the auxiliary heater 23 and the radiator 4 when the auxiliary heater 23 operates) is blown out from the outlets 29A to 29C, this heats the vehicle interior. become.
The heat pump controller 32 calculates a target radiator pressure PCO (target value of the radiator pressure PCI) from the target heater temperature TCO (target value of the heating temperature TH described later) calculated by the air conditioning controller 20 from the target outlet temperature TAO. The rotational speed NC of the compressor 2 is controlled based on the target radiator pressure PCO and the refrigerant pressure (radiator pressure PCI, high pressure of the refrigerant circuit R) detected by the radiator pressure sensor 47, and the radiator Control heating by 4. Further, the heat pump controller 32 opens the outdoor expansion valve 6 based on the refrigerant temperature (the radiator temperature TCI) of the radiator 4 detected by the radiator temperature sensor 46 and the radiator pressure PCI detected by the radiator pressure sensor 47. The degree of subcooling SC of the refrigerant at the outlet of the radiator 4 is controlled.
In the heating mode, if the heating capacity required by the radiator 4 is insufficient with respect to the heating capacity required for air conditioning in the vehicle compartment, the heat pump controller 32 compensates for the shortage by the heat generation of the auxiliary heater 23. The energization of the auxiliary heater 23 is controlled. Thereby, comfortable heating of the vehicle interior is realized, and frost formation on the outdoor heat exchanger 7 is also suppressed. At this time, since the auxiliary heater 23 is disposed on the air upstream side of the radiator 4, the air flowing through the air flow passage 3 is ventilated to the auxiliary heater 23 in front of the radiator 4.
Here, when the auxiliary heater 23 is disposed on the air downstream side of the radiator 4, when the auxiliary heater 23 is configured by the PTC heater as in the embodiment, the temperature of the air flowing into the auxiliary heater 23 is the radiator Because the resistance value of the PTC heater increases and the current value also decreases and the calorific value decreases, the auxiliary heater 23 is disposed on the air upstream side of the radiator 4 in the embodiment. As described above, the capability of the auxiliary heater 23 composed of a PTC heater can be sufficiently exhibited.
(2) Dehumidifying heating mode
Next, in the dehumidifying and heating mode, the heat pump controller 32 opens the solenoid valve 17 and closes the solenoid valve 21. Further, the solenoid valve 30 is closed, the solenoid valve 40 is opened, and the degree of opening of the outdoor expansion valve 6 is fully closed. Then, the compressor 2 is operated. The air conditioning controller 20 operates the blowers 15 and 27, and the air mix damper 28 is basically blown out from the indoor blower 27 and passes through the heat absorber 9 and all the air in the air flow passage 3 is heated by the heat exchange passage 3A. In the state of ventilating to the auxiliary heater 23 and the radiator 4, the air volume is also adjusted.
As a result, the high-temperature, high-pressure gas refrigerant discharged from the compressor 2 to the refrigerant pipe 13G flows into the bypass pipe 35 without going to the radiator 4, and passes through the solenoid valve 40 and the refrigerant pipe on the downstream side of the outdoor expansion valve 6 It will reach 13E. At this time, since the outdoor expansion valve 6 is fully closed, the refrigerant flows into the outdoor heat exchanger 7. The refrigerant flowing into the outdoor heat exchanger 7 is air-cooled and condensed by traveling there or by the outside air ventilated by the outdoor blower 15. The refrigerant leaving the outdoor heat exchanger 7 flows from the refrigerant pipe 13A through the solenoid valve 17 into the receiver dryer portion 14 and the supercooling portion 16 sequentially. Here, the refrigerant is subcooled.
The refrigerant leaving the subcooling section 16 of the outdoor heat exchanger 7 enters the refrigerant pipe 13B, passes through the internal heat exchanger 19, and reaches the indoor expansion valve 8. After the refrigerant is depressurized by the indoor expansion valve 8, the refrigerant flows into the heat absorber 9 and evaporates. At this time, the air blown out from the indoor blower 27 is cooled by the heat absorption action, and the moisture in the air condenses and adheres to the heat absorber 9, so the air in the air flow passage 3 is cooled, and Dehumidified. The refrigerant evaporated by the heat absorber 9 passes through the internal heat exchanger 19 and reaches the accumulator 12 via the refrigerant pipe 13C, and the circulation through which the refrigerant is sucked into the compressor 2 is repeated.
At this time, since the valve opening degree of the outdoor expansion valve 6 is fully closed, it is possible to suppress or prevent the disadvantage that the refrigerant discharged from the compressor 2 flows back from the outdoor expansion valve 6 into the radiator 4 It becomes. As a result, it is possible to suppress or eliminate the decrease in the refrigerant circulation amount and secure the air conditioning capacity. Further, in the dehumidifying and heating mode, the heat pump controller 32 supplies power to the auxiliary heater 23 to generate heat. Thus, the air cooled by the heat absorber 9 and dehumidified is further heated in the process of passing through the auxiliary heater 23, and the temperature rises, so that dehumidifying and heating of the passenger compartment is performed.
The heat pump controller 32 is a compressor based on the temperature of the heat absorber 9 detected by the heat absorber temperature sensor 48 (heat absorber temperature Te) and the target heat absorber temperature TEO which is a target value of the heat absorber temperature Te calculated by the air conditioning controller 20. Of the auxiliary heater 23 based on the auxiliary heater temperature Tptc detected by the auxiliary heater temperature sensor 50 and the aforementioned target heater temperature TCO (in this case, the target value of the auxiliary heater temperature Tptc). By controlling the energization (heating by heat generation) and appropriately performing cooling and dehumidifying of the air in the heat absorber 9, the temperature of the air blown out into the vehicle compartment from the respective blowout ports 29A to 29C by heating by the auxiliary heater 23. Prevent the decline properly. As a result, it is possible to control the temperature to an appropriate heating temperature while dehumidifying the air blown out into the vehicle compartment, and to realize comfortable and efficient dehumidifying and heating of the vehicle interior.
In addition, since the auxiliary heater 23 is disposed on the air upstream side of the radiator 4, the air heated by the auxiliary heater 23 passes through the radiator 4, but in this dehumidifying and heating mode, the refrigerant 4 Since the air is not flowed, the problem that the radiator 4 absorbs heat from the air heated by the auxiliary heater 23 is also eliminated. That is, the decrease in the temperature of the air blown out into the vehicle interior by the radiator 4 is suppressed, and the COP is also improved.
(3) Dehumidifying cooling mode
Next, in the dehumidifying and cooling mode, the heat pump controller 32 opens the solenoid valve 17 and closes the solenoid valve 21. Also, the solenoid valve 30 is opened and the solenoid valve 40 is closed. Then, the compressor 2 is operated. The air conditioning controller 20 operates the blowers 15 and 27, and the air mix damper 28 is basically blown out from the indoor blower 27 and passes through the heat absorber 9 and all the air in the air flow passage 3 is heated by the heat exchange passage 3A. In the state of ventilating to the auxiliary heater 23 and the radiator 4, the air volume is also adjusted.
As a result, the high temperature and high pressure gas refrigerant discharged from the compressor 2 passes through the solenoid valve 30 and flows into the radiator 4 from the refrigerant pipe 13G. Since the air in the air flow passage 3 is ventilated to the radiator 4, the air in the air flow passage 3 is heated by the high temperature refrigerant in the radiator 4, while the refrigerant in the radiator 4 heats the air. It is taken away, cooled, and condensed and liquefied.
The refrigerant leaving the radiator 4 passes through the refrigerant pipe 13E to reach the outdoor expansion valve 6, and then flows into the outdoor heat exchanger 7 through the outdoor expansion valve 6 which is controlled to be open. The refrigerant flowing into the outdoor heat exchanger 7 is air-cooled and condensed by traveling there or by the outside air ventilated by the outdoor blower 15. The refrigerant leaving the outdoor heat exchanger 7 flows from the refrigerant pipe 13A through the solenoid valve 17 into the receiver dryer portion 14 and the supercooling portion 16 sequentially. Here, the refrigerant is subcooled.
The refrigerant leaving the subcooling section 16 of the outdoor heat exchanger 7 enters the refrigerant pipe 13B, passes through the internal heat exchanger 19, and reaches the indoor expansion valve 8. After the refrigerant is depressurized by the indoor expansion valve 8, the refrigerant flows into the heat absorber 9 and evaporates. At this time, the moisture in the air blown out from the indoor blower 27 condenses and adheres to the heat sink 9, so that the air is cooled and dehumidified.
The refrigerant evaporated by the heat absorber 9 passes through the internal heat exchanger 19 and reaches the accumulator 12 via the refrigerant pipe 13C, and the circulation through which the refrigerant is sucked into the compressor 2 is repeated. In this dehumidifying and cooling mode, the heat pump controller 32 does not energize the auxiliary heater 23, so the air cooled by the heat absorber 9 and dehumidified air passes through the radiator 4 and is reheated (heat radiation capacity is lower than that during heating) Be done. As a result, dehumidifying and cooling of the passenger compartment is performed.
The heat pump controller 32 detects the temperature of the heat absorber 9 (heat absorber temperature Te) detected by the heat absorber temperature sensor 48 and the target heat absorber temperature TEO (sent from the air conditioning controller 20) as its target value. Control the rotational speed NC. Further, the heat pump controller 32 calculates the target radiator pressure PCO from the target heater temperature TCO described above, and the target radiator pressure PCO and the refrigerant pressure of the radiator 4 detected by the radiator pressure sensor 47 (the radiator pressure PCI. The valve opening degree of the outdoor expansion valve 6 is controlled based on the high pressure of the refrigerant circuit R, and the heating by the radiator 4 is controlled.
(4) Cooling mode
Next, in the cooling mode, the heat pump controller 32 fully opens the outdoor expansion valve 6 in the dehumidifying and cooling mode. Then, the compressor 2 is operated and the auxiliary heater 23 is not energized. The air conditioning controller 20 operates the blowers 15, 27. The air mix damper 28 is blown out from the indoor blower 27 and the air in the air flow passage 3 which has passed through the heat absorber 9 is the auxiliary heater 23 of the heating heat exchange passage 3A. And let it be in the state which adjusts the ratio ventilated to the radiator 4. FIG.
As a result, the high temperature / high pressure gas refrigerant discharged from the compressor 2 flows from the refrigerant pipe 13G to the radiator 4 through the solenoid valve 30, and the refrigerant leaving the radiator 4 passes through the refrigerant pipe 13E to the outdoor expansion valve 6 Lead to At this time, since the outdoor expansion valve 6 is fully opened, the refrigerant passes through it and flows into the outdoor heat exchanger 7 where it is cooled by air or by the outside air ventilated by the outdoor blower 15 by running. Liquefy. The refrigerant leaving the outdoor heat exchanger 7 flows from the refrigerant pipe 13A through the solenoid valve 17 into the receiver dryer portion 14 and the supercooling portion 16 sequentially. Here, the refrigerant is subcooled.
The refrigerant leaving the subcooling section 16 of the outdoor heat exchanger 7 enters the refrigerant pipe 13B, passes through the internal heat exchanger 19, and reaches the indoor expansion valve 8. After the refrigerant is depressurized by the indoor expansion valve 8, the refrigerant flows into the heat absorber 9 and evaporates. The air blown out from the indoor blower 27 is cooled by the heat absorption action at this time. Further, the moisture in the air condenses and adheres to the heat absorber 9.
The refrigerant evaporated by the heat absorber 9 passes through the internal heat exchanger 19 and reaches the accumulator 12 via the refrigerant pipe 13C, and the circulation through which the refrigerant is sucked into the compressor 2 is repeated. The air cooled by the heat absorber 9 and dehumidified is blown out from the blowout ports 29A to 29C into the vehicle compartment (a part of the air passes through the radiator 4 for heat exchange). It will be done. Further, in the cooling mode, the heat pump controller 32 generates the compressor 2 based on the temperature (heat absorber temperature Te) of the heat absorber 9 detected by the heat absorber temperature sensor 48 and the target heat absorber temperature TEO described above, which is its target value. Control the number of revolutions NC.
(5) MAX cooling mode (maximum cooling mode)
Next, in the MAX cooling mode as the maximum cooling mode, the heat pump controller 32 opens the solenoid valve 17 and closes the solenoid valve 21. Further, the solenoid valve 30 is closed, the solenoid valve 40 is opened, and the degree of opening of the outdoor expansion valve 6 is fully closed. Then, the compressor 2 is operated and the auxiliary heater 23 is not energized. The air conditioning controller 20 operates the blowers 15 and 27, and the air mix damper 28 is blown out from the indoor blower 27 and the air in the air flow passage 3 having passed through the heat absorber 9 is an auxiliary heater of the heating heat exchange passage 3A. 23 and the radiator 4 are adjusted.
As a result, the high-temperature, high-pressure gas refrigerant discharged from the compressor 2 to the refrigerant pipe 13G flows into the bypass pipe 35 without going to the radiator 4, and passes through the solenoid valve 40 and the refrigerant pipe on the downstream side of the outdoor expansion valve 6 It will reach 13E. At this time, since the outdoor expansion valve 6 is fully closed, the refrigerant flows into the outdoor heat exchanger 7. The refrigerant flowing into the outdoor heat exchanger 7 is air-cooled and condensed by traveling there or by the outside air ventilated by the outdoor blower 15. The refrigerant leaving the outdoor heat exchanger 7 flows from the refrigerant pipe 13A through the solenoid valve 17 into the receiver dryer portion 14 and the supercooling portion 16 sequentially. Here, the refrigerant is subcooled.
The refrigerant leaving the subcooling section 16 of the outdoor heat exchanger 7 enters the refrigerant pipe 13B, passes through the internal heat exchanger 19, and reaches the indoor expansion valve 8. After the refrigerant is depressurized by the indoor expansion valve 8, the refrigerant flows into the heat absorber 9 and evaporates. The air blown out from the indoor blower 27 is cooled by the heat absorption action at this time. Further, since the moisture in the air condenses and adheres to the heat absorber 9, the air in the air flow passage 3 is dehumidified. The refrigerant evaporated by the heat absorber 9 passes through the internal heat exchanger 19 and reaches the accumulator 12 via the refrigerant pipe 13C, and the circulation through which the refrigerant is sucked into the compressor 2 is repeated. At this time, since the outdoor expansion valve 6 is fully closed, it is possible to similarly suppress or prevent the problem that the refrigerant discharged from the compressor 2 flows back from the outdoor expansion valve 6 into the radiator 4 . As a result, it is possible to suppress or eliminate the decrease in the refrigerant circulation amount and secure the air conditioning capacity.
Here, since a high temperature refrigerant flows to the radiator 4 in the cooling mode described above, direct heat conduction from the radiator 4 to the HVAC unit 10 occurs not a little, but the refrigerant in the radiator 4 in this MAX cooling mode Since the air does not flow, the heat transferred from the radiator 4 to the HVAC unit 10 also prevents the air in the air flow passage 3 from the heat absorber 9 from being heated. Therefore, strong cooling of the vehicle interior is performed, and particularly in an environment where the outside air temperature Tam is high, it is possible to cool the vehicle interior quickly to realize comfortable vehicle interior air conditioning. Also in the MAX cooling mode, the heat pump controller 32 generates a compressor based on the temperature (heat absorber temperature Te) of the heat absorber 9 detected by the heat absorber temperature sensor 48 and the target heat absorber temperature TEO described above, which is its target value. Control the rotation speed NC of 2.
(6) Auxiliary heater only mode
In addition, the control device 11 of the embodiment stops the compressor 2 of the refrigerant circuit R and the outdoor fan 15 and applies electricity to the auxiliary heater 23 when excessive frost formation occurs on the outdoor heat exchanger 7 as described later. There is an auxiliary heater only mode in which the passenger compartment is heated with only the auxiliary heater 23. Also in this case, the heat pump controller 32 controls the energization (heat generation) of the auxiliary heater 23 based on the auxiliary heater temperature Tptc detected by the auxiliary heater temperature sensor 50 and the target heater temperature TCO described above.
In addition, the air conditioning controller 20 operates the indoor fan 27, and the air mix damper 28 ventilates the air in the air flow path 3 blown out from the indoor fan 27 to the auxiliary heater 23 of the heating heat exchange path 3A to obtain the air volume. It will be in the state to adjust. Since the air heated by the auxiliary heater 23 is blown out into the vehicle compartment from the air outlets 29A to 29C, this heats the vehicle interior.
(7) Switching of operation mode
The air conditioning controller 20 calculates the above-described target blowout temperature TAO from the following formula (I). The target blowing temperature TAO is a target value of the temperature of air blown out into the vehicle compartment.
TAO = (Tset−Tin) × K + Tbal (f (Tset, SUN, Tam))
(I)
Here, Tset is the set temperature of the vehicle interior set by the air conditioning operation unit 53, Tin is the indoor temperature detected by the inside air temperature sensor 37, K is a coefficient, Tbal is the set temperature Tset, and the amount of solar radiation detected by the solar radiation sensor 51 SUN, it is a balance value calculated from the outside air temperature Tam detected by the outside air temperature sensor 33. Generally, the target blowing temperature TAO is higher as the outside air temperature Tam is lower, and decreases as the outside air temperature Tam increases.
The heat pump controller 32 selects one of the above operation modes based on the outside air temperature Tam (detected by the outside air temperature sensor 33) transmitted from the air conditioning controller 20 via the vehicle communication bus 65 at the time of startup and the target blowout temperature TAO. The operation mode is selected, and each operation mode is transmitted to the air conditioning controller 20 via the vehicle communication bus 65. After startup, the outside air temperature Tam, the humidity inside the vehicle compartment, the target air outlet temperature TAO, the heating temperature TH (the temperature of the air on the downwind side of the radiator 4; estimated value), the target heater temperature TCO, the heat sink temperature Te, By switching each operation mode based on parameters such as target heat sink temperature TEO and presence or absence of dehumidification demand in the vehicle compartment, heating mode, dehumidification heating mode, dehumidification can be properly performed according to environmental conditions and necessity of dehumidification By switching the cooling mode, the cooling mode, the MAX cooling mode, and the auxiliary heater single mode to control the temperature of the air blown into the vehicle compartment to the target blowing temperature TAO, a comfortable and efficient vehicle interior air conditioning is realized.
(8) Control of the compressor 2 in the heating mode by the heat pump controller 32
Next, the control of the compressor 2 in the heating mode described above will be described in detail with reference to FIG. FIG. 4 is a control block diagram of the heat pump controller 32 for determining the target rotational speed (compressor target rotational speed) TGNCh of the compressor 2 for the heating mode. The F / F (feed forward) operation amount calculator 58 of the heat pump controller 32 calculates the outside air temperature Tam obtained from the outside air temperature sensor 33, the blower voltage BLV of the indoor fan 27, and SW = (TAO-Te) / (TH-Te). And the target supercooling degree TGSC, which is the target value of the subcooling degree SC at the outlet of the radiator 4, and the target heater described above, which is the target value of the heating temperature TH described later. Based on the temperature TCO (sent from the air conditioning controller 20) and the target radiator pressure PCO which is the target value of the pressure of the radiator 4, the F / F operation amount TGNChff of the compressor target rotation number is calculated.
Here, the above-mentioned TH for calculating the air volume ratio SW is the temperature of air on the leeward side of the radiator 4 (hereinafter referred to as a heating temperature), and the heat pump controller 32 calculates the first-order lag calculation formula (II) below. presume.
TH = (INTL × TH0 + Tau × THz) / (Tau + INTL) ··· (II)
Here, INTL is a calculation cycle (constant), Tau is a first-order lag time constant, TH0 is a steady-state value of the heating temperature TH in a steady state before the first-order lag calculation, and THz is a previous value of the heating temperature TH. By estimating the heating temperature TH in this manner, it is not necessary to provide an extra temperature sensor.
The heat pump controller 32 changes the time constant Tau and the steady-state value TH0 in accordance with the above-described operation mode to make the above-described estimation equation (II) different depending on the operation mode, thereby estimating the heating temperature TH. The heating temperature TH is transmitted to the air conditioning controller 20 via the vehicle communication bus 65.
The target radiator pressure PCO is calculated by the target value calculator 59 based on the target degree of supercooling TGSC and the target heater temperature TCO. Further, the F / B (feedback) manipulated variable computing unit 60 computes the F / B manipulated variable TGNChfb of the compressor target rotational speed based on the target radiator pressure PCO and the radiator pressure PCI which is the refrigerant pressure of the radiator 4 Do. The F / F manipulated variable TGNCnff computed by the F / F manipulated variable computing unit 58 and TGNChfb computed by the F / B manipulated variable computing unit 60 are added by the adder 61, and the limit setting unit 62 sets the control upper limit value ECNpdLimHi After the control lower limit value ECNpdLimLo is limited, it is determined as the compressor target rotation speed TGNCh. In the heating mode, the heat pump controller 32 controls the rotation speed NC of the compressor 2 based on the compressor target rotation speed TGNCh.
(9) Control of the compressor 2 and the auxiliary heater 23 in the dehumidifying and heating mode by the heat pump controller 32
On the other hand, FIG. 5 is a control block diagram of the heat pump controller 32 for determining the target rotational speed (compressor target rotational speed) TGNCc of the compressor 2 for the dehumidifying and heating mode. The F / F operation amount calculation unit 63 of the heat pump controller 32 is a target heat radiation that is a target value of the outside air temperature Tam, the volumetric air flow rate Ga of the air flowing into the air flow passage 3, and the pressure of the radiator 4 (radiator pressure PCI). The F / F manipulated variable TGNCcff of the compressor target rotational speed is calculated based on the target pressure T.sub.o of the heat sink 9 and the target heat sink temperature T.sub.oO which is the target value of the temperature of the heat sink 9 (the heat sink temperature Te).
Further, the F / B manipulated variable computing unit 64 computes the F / B manipulated variable TGNCcfb of the compressor target rotational speed based on the target heat absorber temperature TEO (transmitted from the air conditioning controller 20) and the heat absorber temperature Te. The F / F operation amount TGNCcff calculated by the F / F operation amount calculation unit 63 and the F / B operation amount TGNCcfb calculated by the F / B operation amount calculation unit 64 are added by the adder 66 and the limit setting unit 67 After the control upper limit value TGNCcLimHi and the control lower limit value TGNCcLimLo are limited, the compressor target rotational speed TGNCc is determined. In the dehumidifying and heating mode, the heat pump controller 32 controls the rotation speed NC of the compressor 2 based on the compressor target rotation speed TGNCc.
FIG. 6 is a control block diagram of the heat pump controller 32 for determining the auxiliary heater request capacity TGQPTC of the auxiliary heater 23 in the dehumidifying and heating mode. The target heater temperature TCO and the auxiliary heater temperature Tptc are input to the subtractor 73 of the heat pump controller 32, and the deviation (TCO-Tptc) of the target heater temperature TCO and the auxiliary heater temperature Tptc is calculated. The deviation (TCO-Tptc) is input to the F / B control unit 74, and the F / B control unit 74 eliminates the deviation (TCO-Tptc) and the auxiliary heater temperature Tptc becomes the target heater temperature TCO. Calculate the required ability F / B operation amount.
The auxiliary heater required capacity F / B manipulated variable Qafb calculated by the F / B control unit 74 is limited by the limit setting unit 76 with the control upper limit value QptcLimHi and the control lower limit value QptcLimLo as an auxiliary heater required capacity TGQPTC. It is determined. In the dehumidifying and heating mode, the controller 32 controls the energization of the auxiliary heater 23 based on the auxiliary heater request capability TGQPTC to generate (heat) the auxiliary heater 23 so that the auxiliary heater temperature Tptc becomes the target heater temperature TCO. Control.
Thus, in the dehumidifying and heating mode, the heat pump controller 32 controls the operation of the compressor based on the heat absorber temperature Te and the target heat absorber temperature TEO, and controls the heat generation of the auxiliary heater 23 based on the target heater temperature TCO. Thus, the cooling and the dehumidification by the heat absorber 9 in the dehumidifying and heating mode, and the heating by the auxiliary heater 23 are properly controlled. As a result, it is possible to control the temperature to a more accurate heating temperature while dehumidifying the air blown out into the vehicle compartment more appropriately, and realize more comfortable and efficient dehumidifying heating of the vehicle interior. Will be able to In the control block of the auxiliary heater 23 in the heating mode in this embodiment and the embodiment 2 described later, the target heater temperature TCO in FIG. 6 is replaced with the target auxiliary heater temperature THO (target value of the auxiliary heater temperature Tptc). Become a shape. Further, in the dehumidifying and heating mode of this embodiment, the auxiliary heater 23 is controlled as target auxiliary heater temperature THO = target heater temperature TCO (FIG. 6), but in the heating mode in this embodiment and embodiment 2 described later As described above, the insufficient heating capacity by the radiator 4 is compensated by the heat generation of the auxiliary heater 23. Therefore, the target auxiliary heater temperature THO is derived from this deficiency, and the target auxiliary heater temperature THO and the auxiliary heater temperature derived. The auxiliary heater 23 is F / B controlled by Tptc.
(10) Control of the air mix damper 28
Next, control of the air mix damper 28 by the air conditioning controller 20 will be described with reference to FIG. In FIG. 3, Ga is the volumetric air volume of the air flowing into the air flow passage 3 described above, Te is the heat absorber temperature, and TH is the heating temperature described above (temperature of the air on the leeward side of the radiator 4).
Based on the air volume ratio SW for ventilating the radiator 4 and the auxiliary heater 23 of the heating heat exchange passage 3A calculated by the equation (following equation (III)) as described above, the air conditioning controller 20 The air mix damper 28 is controlled to adjust the amount of ventilation to the radiator 4 (and the auxiliary heater 23).
SW = (TAO-Te) / (TH-Te) · · (III)
That is, the air volume ratio SW ventilated to the radiator 4 and the auxiliary heater 23 of the heating heat exchange passage 3A changes in the range of 0 ≦ SW ≦ 1, and “0” does not ventilate the heating heat exchange passage 3A. Completely closes the air mix fully ventilating all the air in the air flow passage 3 to the bypass passage 3B, fully drafts all the air in the air flow passage 3 to the heating heat exchange passage 3A at "1". It becomes. That is, the air volume to the radiator 4 is Ga × SW.
(11) Determination of frost formation on the outdoor heat exchanger and control of the compressor etc. accompanying it
As described above, in the heating mode, the refrigerant evaporates in the outdoor heat exchanger 7 and absorbs heat from the outside air to become a low temperature. Therefore, the moisture in the outside air adheres to the outdoor heat exchanger 7 as frost. When this frost formation grows, the heat exchange between the outdoor heat exchanger 7 and the outside air ventilated thereto is hindered, so the operating efficiency of the compressor 2 is lowered. In addition, if the over frost occurs, the outdoor fan 15 or the like may be damaged. Therefore, the heat pump controller 32 determines the progress of frost formation on the outdoor heat exchanger 7 as follows.
(11-1) Determination of the progress of frost formation on the outdoor heat exchanger and control of the compressor, etc. (Part 1)
Next, determination of the progress of frost formation on the outdoor heat exchanger 7 and an example of control of the compressor 2 and defrosting based on the determination will be described using FIG. 7. In this embodiment, the heat pump controller 32 detects the current refrigerant evaporation temperature TXO of the outdoor heat exchanger 7 obtained from the outdoor heat exchanger temperature sensor 54 and the outside air is not frosted on the outdoor heat exchanger 7 in a low humidity environment. Based on the refrigerant evaporation temperature TXObase of the outdoor heat exchanger 7 at the time of frost formation, the state of progress of frost formation on the outdoor heat exchanger 7 is determined.
The heat pump controller 32 first determines whether the vehicle has been activated (IG ON) in step S1 of FIG. 7 and whether there is a request for air conditioning of the passenger compartment by the air conditioning device 1 for the vehicle (hereinafter referred to as HP air conditioning request) Judge whether or not. In this case, it is determined from the ON information (sent from the air conditioning controller 20) of the ignition (IG) whether or not the vehicle is activated. Further, the HP air conditioning request is an operation request for the air conditioning system 1 for a vehicle, and in the embodiment, the ON / OFF switch of the air conditioner provided in the air conditioning operation unit 53 is turned ON whether or not there is the HP air conditioning request. It judges from the information (it transmitted from the air conditioning controller 20) of whether it was.
Then, when the vehicle is activated and the HP air conditioning request is made, the heat pump controller 32 proceeds to step S2, and in the case of no, the heat pump controller 32 proceeds to step S18. In step S18, the heat pump controller 32 determines whether there is an HP air conditioning request, and if there is an HP air conditioning request, that is, if there is an HP air conditioning request regardless of whether the vehicle has been started or not. If it is determined in step S18 that there is no HP air conditioning request, the process proceeds to step S19.
In step S2, the heat pump controller 32 determines whether or not the vehicle air conditioner 1 (HP) is determined to have a failure, and if the failure is determined, the heat pump controller 32 proceeds to step S12 and stops the compressor 2 Permission). On the other hand, if no failure determination is made in step S2, the process proceeds to step S3, and it is determined whether the heavy frost formation flag fFST2 is currently reset ("0"). Assuming that the heavy frost formation flag fFST2 is currently reset, the heat pump controller 32 proceeds to step S4, and determines whether the current operation mode is the heating mode.
Then, if the current operation mode is the heating mode, the process proceeds to step S5, and the difference ΔTXO (ΔTXO = TXObase-TXO) between the refrigerant evaporation temperature TXObase at the time of no frosting and the current refrigerant evaporation temperature TXO is calculated (calculated) Do. In this case, the heat pump controller 32 estimates the refrigerant evaporation temperature TXObase of the outdoor heat exchanger 7 at the time of no frosting by using the following equation (IV).
TXObase = f (Tam, NC, Ga * SW, VSP, PCI)
= K1 x Tam + k2 x NC + k3 x Ga * SW + k4 x VSP + k5 x PCI
(IV)
Here, the parameter Tam of equation (IV) is the outside air temperature obtained from the outside air temperature sensor 33, NC is the number of revolutions of the compressor 2, Ga * SW is the air flow to the radiator 4 (and the auxiliary heater 23), VSP Is a vehicle speed obtained from the vehicle speed sensor 52, PCI is a radiator pressure, and k1 to k5 are coefficients, which are obtained in advance by experiment.
The outside air temperature Tam is an index indicating the suction air temperature (environmental condition) of the outdoor heat exchanger 7. The lower the outside air temperature Tam (the suction air temperature of the outdoor heat exchanger 7), the lower TXObase tends to be. Therefore, the coefficient k1 is a positive value. Similarly, the index indicating the suction air temperature of the outdoor heat exchanger 7 is not limited to the outside air temperature Tam.
Further, the rotation speed NC of the compressor 2 is an index indicating the flow rate (operating condition) of the refrigerant in the refrigerant circuit R, and the higher the rotation speed NC (the larger the flow rate of the refrigerant), the lower TXObase tends to be. Therefore, the coefficient k2 has a negative value.
Further, Ga * SW is an index indicating the amount of air passing through the radiator 4 (operating condition), and the larger the value of Ga * SW (the larger the amount of air passing through the radiator 4), the lower TXObase tends to be. Therefore, the coefficient k3 has a negative value. In addition, as a parameter | index which shows the passing air volume of the radiator 4, not only this but the blower voltage BLV of the indoor air blower 27 may be sufficient.
The vehicle speed VSP is an index indicating the passing wind speed (operating condition) of the outdoor heat exchanger 7, and as the vehicle speed VSP is lower (as the passing wind speed of the outdoor heat exchanger 7 is lower), TXObase tends to be lower. Therefore, the coefficient k4 has a positive value. In addition, as a parameter | index which shows the passing wind speed of the outdoor heat exchanger 7, it may not be this but the voltage of the outdoor air blower 15 may be sufficient.
Further, the radiator pressure PCI is an index indicating the refrigerant pressure (operating condition) of the radiator 4, and as the radiator pressure PCI is higher, TXObase tends to be lower. Therefore, the coefficient k5 has a negative value.
In addition, although the outside air temperature Tam, the rotation speed NC of the compressor 2, the passing air amount Ga * SW of the radiator 4, the vehicle speed VSP, and the radiator pressure PCI are used as parameters of the equation (IV) of this embodiment, The parameters of IV) are not limited to all of the above, and any one of them or a combination thereof may be used.
Then, in step S5, the heat pump controller 32 determines the difference ΔTXO between the refrigerant evaporation temperature TXObase at the time of non-frosting and the current refrigerant evaporation temperature TXO obtained by substituting the current values of the parameters into equation (IV) (ΔTXO Calculate = TXObase-TXO). Next, the heat pump controller 32 determines in step S6 whether or not a predetermined time has elapsed after activation of the heating mode, and if it is in the initial stage of activation and the predetermined time has not elapsed, the process proceeds to step S17 to operate the compressor 2 Continue (HP operation). That is, the compressor 2 is not stopped, and the execution of the heating mode is permitted.
When predetermined time has passed since starting of heating mode by step S6, heat pump controller 32 progresses to step S7, refrigerant evaporation temperature TXO falls rather than refrigerant evaporation temperature TXObase at the time of frost-free, and the difference deltaTXO is predetermined. It is determined whether the normal frosting determination condition of is satisfied.
In this embodiment, in the embodiment, the refrigerant evaporation temperature TXO is lower than the refrigerant evaporation temperature TXObase at the time of no frost formation, and the difference ΔTXO is larger than a first threshold A1 (for example, 3 deg) in the embodiment. When the state continues for the first predetermined time t1 (for example, 60 seconds etc.) and the difference ΔTXO satisfies this normal frosting determination condition, a slight frost is grown on the outdoor heat exchanger 7 It can be judged as a thing.
Then, if the state where the difference ΔTXO is still larger than the first threshold A1 does not continue for the first predetermined time t1, the process proceeds to step S17, and the operation (HP operation) of the compressor 2 is continued. On the other hand, when the state in which the difference ΔTXO is larger than the first threshold A1 continues in the step S7 for the first predetermined time t1, the heat pump controller 32 satisfies the normal frost formation determination condition (the outdoor heat exchanger 7 It is determined that light frost is generated) and defrosting of the outdoor heat exchanger 7 is necessary, and the process proceeds from step S7 to step S8.
Here, in FIG. 9, the solid line indicates the change of the refrigerant evaporation temperature TXO of the outdoor heat exchanger 7, and the broken line indicates the change of the refrigerant evaporation temperature TXObase at the time of no frost formation. In the initial state (non-frosted state) in which the operation is started, the refrigerant evaporation temperature TXO of the outdoor heat exchanger 7 and the refrigerant evaporation temperature TXObase at the time of non-frosting become substantially the same value. The temperature of the vehicle interior is warmed with the progress of the heating mode, and the load of the vehicle air conditioner 1 decreases, so the above-described refrigerant flow rate and the passing air volume of the radiator 4 also decrease, and The calculated TXObase (dotted line in FIG. 9) rises.
On the other hand, when frost formation occurs in the outdoor heat exchanger 7, the heat exchange performance with the outside air is hindered, so the refrigerant evaporation temperature TXO (solid line) gradually decreases and eventually falls below TXObase. Then, a slight frost formation on the outdoor heat exchanger 7 causes the refrigerant evaporation temperature TXO to further decrease, the difference ΔTXO (TXObase-TXO) becomes larger than the first threshold A1, and the state is the first predetermined state. When the time t1 is continued, the heat pump controller 32 determines in step S7 that the difference .DELTA.TXO satisfies the above-described normal frosting determination condition (light frost is generated on the outdoor heat exchanger 7), and the outdoor heat is generated. In step S8, the normal frost formation flag fFST1 is set ("1") (step S7, step S8 is normal frost formation determination).
Next, the heat pump controller 32 proceeds to step S9, and this time, the refrigerant evaporation temperature TXO falls below the refrigerant evaporation temperature TXObase at the time of no frosting, and the difference ΔTXO is a predetermined first heavy frosting judgment condition (first It is determined whether or not the severe frosting determination condition is satisfied.
In the first embodiment, the refrigerant evaporation temperature TXO is lower than the refrigerant evaporation temperature TXObase at the time of no frost formation, and the difference ΔTXO is a second threshold A2 (1) (for example, 15 deg, etc.). Outdoor heat exchange when the second predetermined time t 2 (1) (for example, 30 seconds etc.) continues and the difference ΔTXO satisfies the first severe frost formation determination condition. It can be judged that excessive frost formation has progressed to the vessel 7 in a short time.
Then, if the state in which ΔTXO is still larger than the second threshold A2 (1) does not continue for the second predetermined time t2 (1), the process proceeds to step S16, and this time, ΔTXO is determined to be the predetermined second severe frost formation It is determined whether the condition (another severe frosting determination condition) is satisfied.
In this embodiment, the refrigerant evaporation temperature TXO is lower than the refrigerant evaporation temperature TXObase at the time of no frost formation, and the difference ΔTXO is another second threshold value A2 (2) (for example, in the second heavy frost determination condition) , 5 deg etc.) continues for another second predetermined time t 2 (2) (eg 60 minutes etc.), and the difference ΔTXO satisfies this second severe frosting judgment condition. In this case, it can be determined that moderate frost formation continues on the outdoor heat exchanger 7 for a long time.
Then, if the state in which ΔTXO is still larger than the second threshold A2 (2) does not continue for the second predetermined time t2 (2) in step S16, the process proceeds to step S17 and the operation (HP operation) of the compressor 2 is performed. continue.
The second threshold A2 (1) of the first severe frosting determination condition is extremely larger than the first threshold A1 of the normal frosting determination condition described above, and the second predetermined time t2 (1) is the first Is shorter than the predetermined time t1. The second threshold A2 (2) of the second severe frosting determination condition is larger than the first threshold A1 of the normal frosting determination condition described above, and the second predetermined time t2 (2) is the second It is extremely longer than the predetermined time t1. And these 1st and 2nd severe frost formation determination conditions can determine that frost formation to the outdoor heat exchanger 7 advanced any more than a normal frost formation determination condition.
After the normal frost formation flag fFST1 is set in step S8, frost formation on the outdoor heat exchanger 7 further increases, and the decrease of the refrigerant evaporation temperature TXO shown in FIG. 9 further progresses, and the difference ΔTXO (TXObase-TXO) Is larger than the second threshold value A2 (1), the heat pump controller 32 causes the difference .DELTA.TXO to satisfy the first severe frost formation determination condition in step S9 when the second predetermined time t2 (1) continues. Excessive frost formation has progressed to the outdoor heat exchanger 7 in a short time, and it is determined that defrosting of the outdoor heat exchanger 7 is necessary, and the process proceeds to step S10.
When the difference ΔTXO continues to be larger than another second threshold A2 (2) continues for another second predetermined time t2 (2), the heat pump controller 32 generates the difference ΔTXO at step S16. The severe frost formation determination condition of 2 is satisfied, and moderate frost formation continues for a long time in the outdoor heat exchanger 7, and it is determined that defrosting of the outdoor heat exchanger 7 is necessary, and the process proceeds to step S10. Then, the heat pump controller 32 sets the heavy frost formation flag fFST2 ("1") in this step S10, and proceeds to step S11 (the heavy frost formation determination in step S9, step S16, and step S10).
The heat pump controller 32 includes a non-volatile memory (EEP-ROM) 80, and sets the normal frosting flag fFST1 and the heavy frosting flag fFST2 ("1") and resets ("0"). The normal frosting flag fFST1 and the heavy frosting flag are stored in the non-volatile memory 80 and the vehicle air conditioner 1 is stopped and the power of the control device 11 (the air conditioning controller 20 and the heat pump controller 32) is turned off. It is assumed that the state of fFST2 is held in the non-volatile memory 80.
In step S11, the heat pump controller 32 determines whether the heating temperature TH, which is the temperature of the air downstream of the radiator 4, is lower than the target heater temperature TCO-α (α is a relatively small differential), which is its target value. . The target heater temperature TCO calculated from the target air outlet temperature TAO as described above is a required capacity in the heating mode of the air conditioning apparatus 1 for a vehicle. When the auxiliary heater 23 does not generate heat, the heating temperature TH indicates the current heating capacity of the radiator 4. Therefore, when TH ≧ TCO−α (ie, TCO−TH ≦ α), the heating capacity of the radiator 4 satisfies the required capacity. Then, in a situation where the heating capacity of the radiator 4 satisfies the required capacity (No in step S11), the heat pump controller 32 proceeds to step S17 and continues the operation of the compressor 2.
On the other hand, if the heating temperature TH is lower than the target heater temperature TCO in step S11 and the difference is larger than α (Yes: the heating capacity of the radiator 4 does not satisfy the required capacity), the heat pump controller 32 proceeds to step S12. Proceed to stop the compressor 2 (HP operation not permitted). That is, when the difference ΔTXO satisfies the first or second heavy frosting determination condition described above and the heavy frosting flag fFST2 is set, and the heating temperature TH is lower than the target heater temperature TCO and the difference is larger than α. The heat pump controller 32 prohibits the operation of the compressor 2 because it is determined that the heat pump operation more than this is difficult.
Then, the heat pump controller 32 proceeds to step S13, and performs the same heating operation as the above-described auxiliary heater only mode in which the auxiliary heater 23 is energized to heat the vehicle interior. That is, the heat pump controller 32 stops the compressor 2 and the outdoor blower 15 of the refrigerant circuit R, energizes the auxiliary heater 23, and heats the vehicle interior only with the auxiliary heater 23. As long as the severe frost formation flag fFST2 is set (“1”), the heat pump controller 32 proceeds from step S3 to step S11, so in a situation where the heating capacity of the radiator 4 satisfies the required capacity (step The process proceeds to step S17 to continue the operation of the compressor 2 and proceeds to step S12 to prohibit the operation of the compressor 2 in a situation where the operation is not satisfied (YES in step S11). A similar heating of the cabin will be performed.
Next, in step S14, it is determined whether the normal frost formation flag fFST1 described above is set (“1”) or the severe frost formation flag fFST2 is set (“1”), and the normal frost formation flag If fFST1 or severe frost formation flag fFST2 is set ("1"), that is, if it is determined that defrosting of the outdoor heat exchanger 7 is necessary, the process proceeds to step S15, and frosting request is made. The flag fDFSTReq is set ("1"). It is notified from the heat pump controller 32 to the air conditioning controller 20 that the defrost request flag fDFSTReq is set ("1") as the defrost request (FIG. 2).
On the other hand, when the vehicle is activated in step S1 and the HP air conditioning request is not present and the process proceeds to step S18 and there is no HP air conditioning request, the heat pump controller 32 proceeds to step S19. In step S19, the heat pump controller 32 determines whether the defrost request flag fDFSTReq is set ("1"). If reset ("0"), the heat pump controller 32 proceeds to step S24 and is stored in the non-volatile memory 80. The states of the normal frost formation flag fFST1 and the heavy frost formation flag fFST2 are kept as the previous state (previous value).
On the other hand, if the defrosting request flag fDFSTReq is set ("1") in step S15 described above, the heat pump controller 32 proceeds from step S19 to step S20, and whether the defrosting permission is notified from the air conditioning controller 20 or not to decide.
Here, when the air conditioning controller 20 is notified that the defrosting request flag fDFSTReq is set as the defrosting request from the heat pump controller 32 as described above, the current state of the vehicle is the defrosting permission of the outdoor heat exchanger 7 Whether the defrosting of the outdoor heat exchanger 7 is possible or not is determined by determining whether the conditions are satisfied. The defrost permission condition in the case of the embodiment is that there is no HP air conditioning request described above, and the battery 75 is being charged (the vehicle is stopped) or the remaining amount of the battery 75 is equal to or more than a predetermined value.
If the current state of the vehicle satisfies the defrosting permission condition, the air conditioning controller 20 sets ("1") the defrosting permission flag fDFSTPerm. The fact that the defrosting permission flag fDFSTPerm is set ("1") is notified from the air-conditioning controller 20 to the heat pump controller 32 as the defrosting permission (FIG. 2). The heat pump controller 32 proceeds from step S20 to step S21 when the defrosting permission is notified from the air conditioning controller 20, and performs the defrosting operation of the outdoor heat exchanger 7, and proceeds to step S24 when not notified.
The heat pump controller 32 sets the refrigerant circuit R to the heating mode state in the defrosting operation in step S21, then fully opens the outdoor expansion valve 6 and sets the air volume ratio SW by the air mix damper 28 to "0". It is set as the state which does not ventilate to the heat exchange path 3A for heating (it does not ventilate to the radiator 4). Then, the compressor 2 is operated, the high temperature refrigerant discharged from the compressor 2 is made to flow into the outdoor heat exchanger 7 through the radiator 4 and the outdoor expansion valve 6, and the frost formation of the outdoor heat exchanger 7 is performed. Thaw.
Then, in step S22, the heat pump controller 32 determines that the temperature of the outdoor heat exchanger 7 (in this case, the outdoor heat exchanger temperature TXO) detected by the outdoor heat exchanger temperature sensor 54 is a predetermined defrost end temperature (for example, + 3 ° C., etc.) It is judged whether the higher state continues for a predetermined time (for example, several minutes) (defrost completion condition), and defrost of the outdoor heat exchanger 7 is finished and the outdoor heat exchanger temperature TXO is If the defrost termination condition is satisfied, the process proceeds to step S23, and it is determined that the defrosting is completed, and the above-described normal frost formation flag fFST1 and the heavy frost formation flag fFST2 are reset ("0") (step S19 to step S24). Is defrost control).
As a result, when the process proceeds from step S1 to step S2 and step S3 thereafter, the process proceeds to step S4, so that the operation prohibition of the compressor 2 is canceled by the subsequent determination, and it is possible to heat the vehicle interior by the heating mode. Become.
(11-2) Determination of the progress of frost formation on the outdoor heat exchanger and control of the compressor, etc. (Part 2)
Next, another example of the determination of the progress of frost formation of the outdoor heat exchanger 7 and the control of the compressor 2 and the like will be described with reference to FIG. The heat pump controller 32 performs the same control as in FIG. 7 in this example, but the difference ΔTXO in FIG. 7 is replaced with the difference ΔPXO described later. And in this embodiment, the heat pump controller 32 does not form the current refrigerant evaporation pressure PXO of the outdoor heat exchanger 7 obtained from the outdoor heat exchanger pressure sensor 56 and the outdoor air on the outdoor heat exchanger 7 in a low humidity environment. Based on the refrigerant evaporation pressure PXObase of the outdoor heat exchanger 7 at the time of no frost formation, the progress state of frost formation on the outdoor heat exchanger 7 is determined. The heat pump controller 32 in this case estimates the refrigerant evaporation pressure PXObase of the outdoor heat exchanger 7 at the time of no frosting by using the following equation (V).
PXObase = f (Tam, NC, Ga * SW, VSP, PCI)
= K6 x Tam + k7 x NC + k8 x Ga * SW + k9 x VSP + k10 x PCI
(V)
In addition, since each parameter of Formula (V) is the same as Formula (IV), description is abbreviate | omitted. Further, the coefficients k6 to k10 also have the same tendency (positive and negative) as the coefficients k1 to k5 described above.
In FIG. 10, the solid line indicates the change of the refrigerant evaporation pressure PXO of the outdoor heat exchanger 7, and the broken line indicates the change of the refrigerant evaporation pressure PKObase at the time of no frost formation. At the initial stage of startup (non-frost formation), the refrigerant evaporation pressure PKO of the outdoor heat exchanger 7 and the refrigerant evaporation pressure PXObase at the time of no frost formation become substantially the same value. The temperature of the vehicle interior is warmed with the progress of the heating mode, and the load of the vehicle air conditioner 1 decreases, so the above-described refrigerant flow rate and the passing air volume of the radiator 4 also decrease, and in equation (V) The calculated PXObase (dotted line in FIG. 10) rises.
On the other hand, when frost formation occurs in the outdoor heat exchanger 7, the heat exchange performance with the outside air is hindered, so the refrigerant evaporation pressure PKO (solid line) gradually decreases and eventually falls below PKObase. In the case of this embodiment, the heat pump controller 32 substitutes the refrigerant evaporation pressure PXObase at the time of frost-free time obtained by substituting the current values of the parameters into the equation (V) in step S5 of FIG. A difference ΔPXO with the pressure PXO (ΔPXO = PXObase−PXO) is calculated (calculated). Thereafter, control is performed by replacing the difference ΔTXO in step S7, step S9, and step S16 of FIG. 7 with the difference ΔPXO. However, the first threshold A1 and the second threshold A2 (1), A2 (2), and the first predetermined time t1 and the second predetermined time t2 (1), t2 (2) are different from the case of the difference ΔTXO. It shall be different.
Thus, the refrigerant evaporation temperature TXO when the heat pump controller 32 lowers the refrigerant evaporation temperature TXO of the outdoor heat exchanger 7 than the refrigerant evaporation temperature TXObase of the outdoor heat exchanger 7 at the time of no frosting and at the time of no frosting The refrigerant when the refrigerant evaporation pressure PXO of the outdoor heat exchanger 7 is lower than the refrigerant evaporation pressure PXObase of the outdoor heat exchanger 7 at the time of no frost formation based on the difference ΔTXO = TXObase-TXO with the refrigerant evaporation temperature TXObase Based on the difference ΔPXO = PXObase−PXO between the evaporation pressure PXO and the refrigerant evaporation pressure PXObase at the time of no frost formation, the progress of frost formation on the outdoor heat exchanger 7 is determined, and the difference ΔTXO or the difference ΔPXO is predetermined The normal frost formation flag fFST1 is set ("1") when the normal frost formation determination condition of When the frost formation flag fFST1 is set ("1"), the defrost request flag fDFSTReq is set ("1") and a predetermined defrost request is made, and the power of the control device 11 is turned off. Since the normal frosting flag fFST1 is maintained and the heating mode is allowed to be executed, the indoor heat exchanger 7 performs the frost formation in the passenger compartment even when the normal frosting determination condition is satisfied. Heating will be continued. Further, since the state of the normal frost formation flag fFST1 is maintained even if the power of the control device 11 is turned off, the execution of the heating mode is permitted even when the vehicle is stopped and then started.
That is, when the degree of frost formation of the outdoor heat exchanger 7 is such that the normal frost formation determination condition is satisfied, heating of the vehicle interior is continued when the vehicle and the air conditioner 1 for vehicle are in operation. When the vehicle and the vehicle air conditioner 1 are activated, heating can be performed from the time of activation to maintain comfort.
Then, in the embodiment, when the heat pump controller 32 sets the defrost request flag fDFSTReq (“1”) and performs the defrost request, the air conditioning controller 20 determines whether the outdoor heat exchanger 7 can be defrosted or not and permits In this case, since the heat pump controller 32 performs defrosting of the outdoor heat exchanger 7 and resets the normal frost formation flag fFST1 ("0"), the outdoor heat exchanger 7 is defrosted, It becomes possible to suppress the fall of the operating efficiency accompanying frost formation. In this case, since the heat pump controller 32 maintains the state of the normal frost formation flag fFST1 even if the power is turned off, even after the vehicle is temporarily stopped and the power of the air conditioning device 1 for vehicles is turned off, Defrosting of the heat exchanger 7 will be performed reliably.
As for the permission of defrosting of the outdoor heat exchanger 7, as in the embodiment, the air conditioning controller 20 does not have the air conditioning request for the vehicle interior (HP air conditioning request), and the battery 75 for driving the compressor 2 is Defrosting of the outdoor heat exchanger 7 may be permitted on condition that the battery 75 is charging or the remaining amount of the battery 75 is equal to or more than a predetermined value, or other conditions (environmental conditions such as the outside air temperature etc. Or the state of the air conditioner 1 for a vehicle).
Further, as in the embodiment, the control device 11 is configured of the air conditioning controller 20 to which the air conditioning operation unit 53 for performing the air conditioning setting operation of the vehicle compartment is connected, and the heat pump controller 32 for controlling the operation of the compressor 2; When the air conditioning controller 20 and the heat pump controller 32 transmit and receive information via the vehicle communication bus 65, the heat pump controller 32 calculates the difference ΔTXO or the difference ΔPXO as described above, and the difference ΔTXO Or, when the difference ΔPXO satisfies the normal frost formation determination condition, the normal frost formation flag fFST1 is set (“1”), a defrost request is issued to the air conditioning controller 20, and the defrost permission is issued from the air conditioning controller 20. When notified, the outdoor heat exchanger 7 is defrosted, and the normal frost formation flag fFST1 is reset ("0"). If there is a request for defrosting from the heat pump controller 32, the adjustment controller 20 determines whether or not the outdoor heat exchanger 7 is defrostable, and if permitted, sets the defrosting permission flag fDFSTPerm ("1") to By notifying the heat pump controller 32 of the defrosting permission of the outdoor heat exchanger 7, the heating and air conditioning of the vehicle interior can be comfortably performed, and the decrease in the operating efficiency accompanying the frost formation of the outdoor heat exchanger 7 can be appropriately suppressed. You will be able to
Furthermore, in the embodiment, the heat pump controller 32 has first and second heavy frosting judgment conditions for judging that the frost formation on the outdoor heat exchanger 7 has progressed further than the normal frosting judgment condition. When the difference ΔTXO or the difference ΔPXO satisfies any of the severe frost formation determination conditions, the severe frost formation flag fFST2 is set (“1”), and the severe frost formation flag fFST2 is set Also, the defrost request is set by setting the defrost request flag fDFSTReq (“1”) and the defrost request is performed, and the state of the heavy frost formation flag fFST2 is maintained even when the heat pump controller 32 is turned off, and the compressor in the heating mode Since operation 2 is prohibited, frosting on the outdoor heat exchanger 7 proceeds further than the normal frosting decision condition described above, and the first or second severe frosting decision condition is satisfied. In the case where it becomes dry, it is possible to stop the compressor 2 to prevent the further reduction of the operating efficiency and the occurrence of excessive frost formation.
In the embodiment, the two-stage severe frosting determination of the first severe frosting determination condition and the second severe frosting determination condition is performed, but the determination is made on any one of the severe frosting determination conditions. It is good. However, by determining in two steps as in the embodiment, excessive frost formation in the outdoor heat exchanger 7 progresses in a short time, and moderate frost formation in the outdoor heat exchanger 7 continues for a long time Both of what is happening can be determined.
In the embodiment, the auxiliary heater 23 is provided in the heating heat exchange passage 3A of the airflow passage 3, and the heat pump controller 32 determines that the difference ΔTXO or the difference ΔPXO is the first or second severe frost formation determination. When the operation of the compressor 2 is prohibited because the conditions are satisfied, the passenger compartment is heated by the auxiliary heater 23. Therefore, the progress of frost formation on the outdoor heat exchanger 7 is the first or second severity. Even after the frost formation determination condition is satisfied and the operation of the compressor 2 is prohibited, heating of the vehicle interior can be continued by the auxiliary heater 23.
Then, as described above, even when the progress state of frost formation of the outdoor heat exchanger 7 satisfies the first or second severe frost formation determination condition and the defrost request is performed, the air conditioning controller 20 controls the outdoor heat exchanger If it is judged that the defrosting of 7 is possible and permitted, the heat pump controller 32 defrosts the outdoor heat exchanger 7 and resets the heavy frost formation flag fFST 2. Defrosting can be performed to suppress a decrease in operating efficiency associated with frost formation. Also in this case, since the heat pump controller 32 maintains the state of the heavy frost formation flag fFST2 even if the power is turned off, even after the vehicle is temporarily stopped and the power of the vehicle air conditioner 1 is turned off, Defrosting of the outdoor heat exchanger 7 will be performed reliably.
In addition, as for the permission of defrosting of the outdoor heat exchanger 7, also in this case, the air conditioning controller 20 does not have a request for air conditioning of the vehicle interior (HP air conditioning request) as in the embodiment, and for driving the compressor 2 The defrosting of the outdoor heat exchanger 7 may be permitted under the condition that the battery 75 is being charged or the remaining amount of the battery 75 is equal to or more than a predetermined value.
Similarly, as in the embodiment, the control device 11 includes the air conditioning controller 20 to which the air conditioning operation unit 53 for performing the air conditioning setting operation of the passenger compartment is connected, and the heat pump controller 32 for controlling the operation of the compressor 2. If the air conditioning controller 20 and the heat pump controller 32 transmit and receive information via the vehicle communication bus 65, the heat pump controller 32 also calculates the difference ΔTXO or the difference ΔPXO in this case, and When the difference ΔTXO or the difference ΔPXO satisfies the first or second heavy frosting determination condition, the heavy frost formation flag fFST2 is set (“1”), and the defrost request flag fDFSTReq is set (“1”) When the defrost request is issued to the air conditioning controller 20 and the defrost permission is notified from the air conditioning controller 20, the outdoor heat exchanger 7 is removed. And the heavy frost formation flag fFST2 is reset (“0”), and the air conditioning controller 20 determines whether or not the outdoor heat exchanger 7 is capable of defrosting if the defrost request is received from the heat pump controller 32, and permits it. In this case, the defrosting permission flag fDFSTPerm is set (“1”), and the defrosting permission of the outdoor heat exchanger 7 is notified to the heat pump controller 32, so that the vehicle interior can be comfortably heated and air-conditioned, It is possible to appropriately suppress the decrease in the operating efficiency associated with the frost formation on the outdoor heat exchanger 7.
Further, as in the embodiment, the normal frosting determination condition is that the difference ΔTXO or the state where the difference ΔPXO is larger than the first threshold A1 continues for the first predetermined time t1, and the first and second severe frost formations As the determination condition, at least the state in which the difference ΔTXO or the state in which the difference ΔPXO is larger than the second threshold A2 (1) or A2 (2) continues for the second predetermined time t2 (1), t2 (2) Assuming that the thresholds A2 (1) and A2 (2) of 2 are larger than the first threshold A1, the compressor 2 is operated to continue the heating mode according to the degree of frost formation on the outdoor heat exchanger 7. In this case, it is possible to properly make a step-wise determination as to whether to prohibit the operation of the compressor 2.
Note that the first predetermined time t1 and the second predetermined times t2 (1) and t2 (2) of each frost formation determination condition are not limited to the conditions of the embodiment, and for example, the first predetermined time t1 and the second predetermined time Predetermined time t2 (1), t2 (2) are the same, or the second predetermined time t2 (1) is longer than the first predetermined time t1, and the second predetermined time t2 (2) is the first predetermined time. It may be shorter than the time t1, and may be appropriately set according to the apparatus within a range that does not deviate from the purpose (stepwise determination) of the normal frost formation determination condition and the first and second severe frost formation determination conditions.
In addition, as in the embodiment, the heat pump controller 32 generates the refrigerant evaporation temperature TXObase of the outdoor heat exchanger at the time of no frosting based on the environmental condition and / or the index indicating the operating condition, or the outdoor heat at the time of no frosting. By estimating the refrigerant evaporation pressure PXObase of the exchanger, the progress of frost formation on the outdoor heat exchanger 7 can be accurately detected.
(12) Natural defrosting determination control of outdoor heat exchanger
Next, natural defrosting determination of the outdoor heat exchanger 7 by the heat pump controller 32 and control regarding defrosting in that case will be described with reference to FIG. 8. As described above, the heat pump controller 32 determines that defrosting of the outdoor heat exchanger 7 is necessary, sets the slight frosting flag fFST1 in step S8 of FIG. 7, sets the heavy frosting flag fFST2 in step S10, and finally In step S15, the defrosting request flag fDFSTReq is set, and if defrosting is permitted by the air conditioning controller 20 (defrosting permission flag fDFSTPerm is set), defrosting operation of the outdoor heat exchanger 7 is executed in step S21. However, in an environment where the outside air temperature Tam is relatively high, for example, the frost formed on the outdoor heat exchanger 7 naturally melts.
In addition, frost formed on the outdoor heat exchanger 7 in the heating mode is also the refrigerant in the outdoor heat exchanger 7 if the dehumidifying heating mode, the dehumidifying cooling mode, the cooling mode or the MAX cooling mode in this other embodiment is performed. In this case, frost is also heated from the high-temperature refrigerant to naturally melt (de-ice) and be removed.
Therefore, in this embodiment, after the heat pump controller 32 once determines that the outdoor heat exchanger 7 needs to be defrosted, the outdoor heat exchanger 7 naturally defrosts (de-icing) before the defrosting operation is performed. Judging whether or not it has been done, it does not defrost. Specific control will be described below. That is, in step S25 of FIG. 8 following the flowchart of FIG. 7, the heat pump controller 32 determines whether the vehicle is activated (during ON). Then, if it is activated, the process proceeds to step S26, and in this embodiment, it is determined whether or not the above-described heavy frost formation flag fFST2 is set ("1").
As described above, when it is determined that defrosting of the outdoor heat exchanger 7 is necessary, and the heavy frost formation flag fFST2 is set in step S10 of FIG. 7 and the state is held in the non-volatile memory 80, the heat pump controller 32 In step S27, it is determined whether the defrosting operation of the outdoor heat exchanger 7 is not performed. If the heavy frost formation flag fFST2 is set, but the defrost permission condition is not satisfied and the defrost operation in step S21 of FIG. 7 is not yet executed, the heat pump controller 32 proceeds to step S28 to perform the first natural removal. It is determined whether the frost condition is satisfied.
(12-1) First natural defrosting condition
In the first natural defrosting condition of the embodiment, the outside air temperature Tam detected by the outside air temperature sensor 33 is a predetermined value Tam1 (for example, + 5 ° C. or the like) relatively higher than the freezing point, and an outdoor heat exchanger temperature sensor Refrigerant evaporation temperature TXO of the outdoor heat exchanger 7 detected by 54 (when the refrigerant is radiating by the outdoor heat exchanger 7, etc., when the refrigerant is not evaporated by the outdoor heat exchanger 7, the outlet of the outdoor heat exchanger 7 The state where the refrigerant temperature of (1) is equal to or higher than the outside air temperature Tam-.beta. (.Beta. Is a relatively small predetermined value) continues for a predetermined time t5 (e.g. several tens of minutes etc.).
As in the first natural defrosting condition of the embodiment, when the state where the outside air temperature Tam is relatively high and the refrigerant evaporation temperature TXO of the outdoor heat exchanger 7 is also the outside air temperature Tam-β or more continues for a predetermined time t5, outdoor The frost formation of the heat exchanger 7 is considered to be melted (de-icing) naturally and removed. Therefore, when the first natural defrost condition is satisfied in step S28, the heat pump controller 32 proceeds to step S29 and all frost-related flags, that is, the light frost flag stored in the non-volatile memory 80. fFST1, the heavy frost formation flag fFST2, and the defrost request flag fDFSTReq are reset.
As a result, the air conditioning controller 20 does not set the defrosting permission flag fDFSTPerm, and the heat pump controller 32 does not proceed from step S19 to step S20 either, so the process does not proceed to step S21, and the defrost of the outdoor heat exchanger 7 is performed. Will not take place.
On the other hand, when the vehicle is not activated in step S25, the heat pump controller 32 proceeds to step S30 to determine whether the vehicle is stopped (state of IG OFF not activated), and when stopped, proceeds to step S31. Next, it is determined whether there is a frosting history of the outdoor heat exchanger 7, that is, it is determined whether the light frosting flag fFST1 or the heavy frosting flag fFST2 is set ("1").
(12-2) Second natural defrosting condition
If the light frost formation flag fFST1 or the heavy frost formation flag fFST2 is set in step S7 and the defrosting operation has not been performed yet and they have not been reset, the heat pump controller 32 proceeds to step S32 and is currently starting the vehicle. It is determined whether it is (from IG OFF to ON). Then, if it is in operation, the process proceeds to step S33, and an operation mode other than the heating mode, dehumidifying heating mode in which the refrigerant is not absorbed by the outdoor heat exchanger 7 in the embodiment, dehumidifying cooling mode, cooling mode, MAX cooling mode It is determined whether any one of the above is selected and the operation mode is continued for a predetermined time or more.
An operation mode other than the heating mode is selected, and the fact that the operation mode is continued for a predetermined time or more is a second natural defrost condition. When the dehumidifying / heating mode, the dehumidifying / cooling mode, the cooling mode, and the MAX cooling mode are selected, the refrigerant dissipates heat in the outdoor heat exchanger 7 in this embodiment, so frost formation is melted by the heat of the high temperature refrigerant. It is removed. Therefore, the heat pump controller 32 proceeds to step S29 also when the second natural defrosting condition is satisfied in step S33, and all frost-related flags (light frosting flag fFST1, heavy frosting flag fFST2, and defrosting request) Reset the flag fDFSTReq).
As a result, the air conditioning controller 20 does not set the defrosting permission flag fDFSTPerm, and the heat pump controller 32 does not proceed from step S19 to step S20 either, so the process does not proceed to step S21. Defrosting ceases to occur.
(12-3) Natural defrosting determination based on outside air temperature history (third and fourth natural defrosting conditions)
On the other hand, if the vehicle is not currently activated at step S32, that is, if the vehicle is at rest (IG OFF), the heat pump controller 32 proceeds to step S34 and the nature of the outdoor heat exchanger 7 based on the outdoor temperature history. Perform defrost determination. There are two conditions of the natural defrosting determination based on the outside air temperature history of the embodiment, the third natural defrosting condition and the fourth natural defrosting condition.
(12-3-1) Third natural defrosting condition
The air conditioning controller 20 and the heat pump controller 32 constituting the control device 11 are activated at a predetermined sampling cycle (for example, every one minute) even while the vehicle is stopped, and acquire the outside air temperature Tam detected by the outside air temperature sensor 33 Is stored in the non-volatile memory 80 as a history. The third natural defrosting condition of the embodiment is, as shown in FIG. 11, a predetermined value Tam2 (for example, Tam1) in which the outside air temperature Tam detected by the outside air temperature sensor 33 is relatively higher than the freezing point while the vehicle is stopped. The integrated value of the time which is the same as + 5 ° C. etc. (which may be a different value) is equal to or more than a predetermined time t3 (eg, several tens of minutes).
As in the third natural defrosting condition, if the time when the outside air temperature Tam is relatively high continues for a predetermined time t3 or more while the vehicle is stopped, the frost formation on the outdoor heat exchanger 7 is naturally melted (de-icing) It is believed to be removed. Therefore, while the vehicle is stopped as shown in FIG. 11, the times at which the outside air temperature Tam is equal to or higher than the predetermined value Tam2 are a, b, and c, and their integrated value (a + b + c) is equal to or longer than the predetermined time t3. If it is determined that the heat pump controller 32 determines that the third natural defrosting condition is satisfied in step S34, the process proceeds to step S35, and all frost-related flags (light frosting flag fFST1, heavy frosting The flag fFST2 and the defrost request flag fDFSTReq) are reset.
As a result, the air conditioning controller 20 does not set the defrosting permission flag fDFSTPerm as described above, and the heat pump controller 32 does not proceed from step S19 to step S20 either, so it does not proceed to step S21. Defrosting is no longer performed.
(12-3-2) Fourth natural defrosting condition
Further, as shown in FIG. 12, under the fourth natural defrosting condition of natural defrosting determination based on the outside air temperature history in step S34, the outside air temperature Tam detected by the outside air temperature sensor 33 is a freezing point while the vehicle is stopped. The integral value determined from the difference between the outside air temperature Tam and the predetermined value Tam2 and the elapsed time becomes equal to or greater than the predetermined value X1.
As in the case of the fourth natural defrosting condition, if the outside air temperature Tam becomes relatively high while the vehicle is stopped, and the integral value obtained from the difference from the predetermined value Tam2 and the elapsed time becomes the predetermined value X1, the outdoor heat exchanger The frost formation of 7 is considered to be naturally melted (de-icing) and removed. Therefore, while the vehicle is stopped as shown in FIG. 12, the outside air temperature Tam becomes equal to or higher than the predetermined value Tam2, and a value obtained by integrating the difference (Tam-Tam2) with the elapsed time (the range shown by hatching in FIG. The heat pump controller 32 determines in step S34 that the fourth natural defrosting condition is satisfied, and proceeds to step S35, and all the frost-related flags (mild The frost formation flag fFST1, the heavy frost formation flag fFST2, and the defrost request flag fDFSTReq) are reset.
As a result, the air conditioning controller 20 does not set the defrosting permission flag fDFSTPerm as described above, and the heat pump controller 32 does not proceed from step S19 to step S20 either, so it does not proceed to step S21. Defrosting is no longer performed. In particular, if the difference between the outside air temperature Tam and the predetermined value Tam2 is integrated with the elapsed time as in the fourth natural defrosting condition, the state of natural defrosting of the outdoor heat exchanger 7 can be determined more accurately. Will be able to
(12-4) Fifth natural defrosting condition
Although all of the first to fourth natural defrosting conditions are determined in the embodiment, the present invention is not limited thereto, and any one of them or a combination thereof may be used. In addition to the above-described natural defrosting conditions, the outdoor heat exchanger may also be operated, for example, when a relatively long predetermined period t4 (for example, one month) has elapsed since the vehicle stopped in the determination of step S34 of FIG. The frost formation of 7 is considered to be melted (de-icing) naturally and disappear. Therefore, the process proceeds from step S34 to step S35 so that all frost formation related flags are reset also when the fifth natural defrost condition related to the heat pump controller 32 is satisfied, with the above condition as the fifth natural defrost condition. You may
In the embodiment, the outside air temperature sensor 33 is connected to the air conditioning controller 20, and the outside air temperature Tam is sent to the heat pump controller 32, and the heat pump controller 32 determines the establishment of the natural defrosting condition. The controller 20 may determine the establishment of the natural defrosting condition and notify the heat pump controller 32 of the condition. In that case, the determination in step S28, step S33, and step S34 in FIG. 8 is performed on the air conditioning controller 20 side, and the heat pump controller 32 receives a notification from the air conditioning controller 20 and resets all frost formation related flags. become. Thereby, it is possible to avoid unnecessary defrosting of the outdoor heat exchanger 7 without any trouble. Conversely, the outside air temperature sensor 33 may be connected to the heat pump controller 32, and the outside air temperature Tam may be taken in all by the heat pump controller 32 to make the above-described determination.
As described above, if it is determined that defrosting of the outdoor heat exchanger 7 is necessary, the defrosting of the outdoor heat exchanger 7 is performed if a predetermined natural defrosting condition is satisfied before performing the defrosting operation. If it is not so, even if it is determined that defrosting of the outdoor heat exchanger 7 is necessary, then it is predicted that the predetermined natural defrosting condition is satisfied and the frost formation on the outdoor heat exchanger 7 is naturally melted. In this case, unnecessary defrosting of the outdoor heat exchanger 7 can be avoided in advance by preventing defrosting. Thereby, without performing defrosting of the outdoor heat exchanger 7, in a situation where it is possible to heat the vehicle interior, defrosting is not performed, and comfortable heating and air conditioning of the vehicle interior is realized while contributing to energy saving. Will be able to
In the first natural defrosting condition as in the embodiment, the outside air temperature Tam is the predetermined value Tam1 or more, and the refrigerant evaporation temperature TXO of the outdoor heat exchanger 7 is the outside air temperature Tam-predetermined value β or more. Assuming that the state continues for a predetermined time t5, the second natural defrost condition is selected as an operation mode other than the heating mode (an operation mode in which the refrigerant is not absorbed by the outdoor heat exchanger 7 in this embodiment). Assuming that the integrated value of the time during which the outside air temperature Tam is equal to or higher than the predetermined value Tam2 becomes equal to or longer than the predetermined time t3 while the vehicle is stopped under the third natural defrost condition, the fourth natural defrost condition is While the vehicle is stopped, the outside air temperature Tam is equal to or higher than the predetermined value Tam2, and the integral value obtained from the difference and the elapsed time is equal to or higher than the predetermined value X1, and the vehicle is further subjected to the fifth natural defrost condition. After a predetermined period of time t4 As having passed, it is accurately predicted that the frost formation on the outdoor heat exchanger 7 has naturally melted by judging any of them, a combination thereof, or all of them. become able to.
Further, as in the embodiment, when the control device 11 is configured of the air conditioning controller 20 and the heat pump controller 32, and the air conditioning controller 20 and the heat pump controller 32 transmit and receive information via the vehicle communication bus 65, the heat pump controller 32 However, if it is determined that defrosting of the outdoor heat exchanger 7 is necessary, the predetermined defrost request flag fDFSTReq is set, and if the air conditioning controller 20 sets the predetermined defrost permission flag fDFSTperm, the outdoor heat exchanger 7 is selected. After the defrosting request flag fDFSTReq is reset and the defrosting request flag fDFSTReq is set, the defrosting request flag fDFSTReq is also reset when the natural defrosting condition is satisfied, and the air conditioning controller 20 performs the defrosting request flag fDFSTReq. , By the heat pump controller 32 When the defrosting request flag fDFSTReq is set, it is determined whether the defrosting permission condition is satisfied, and when satisfied, the defrosting permission flag fDFSTPerm is set to make the vehicle interior comfortable. Unnecessary defrosting can also be avoided while appropriately suppressing heating and air conditioning and further lowering the operating efficiency associated with frost formation on the outdoor heat exchanger 7.

Next, FIG. 13 shows a configuration diagram of a vehicle air conditioner 1 of another embodiment to which the present invention is applied. In this figure, the same reference numerals as in FIG. 1 have the same or similar functions. In the case of this embodiment, the outlet of the supercooling unit 16 is connected to the check valve 18, and the outlet of the check valve 18 is connected to the refrigerant pipe 13B. In the check valve 18, the refrigerant pipe 13B (indoor expansion valve 8) side is in the forward direction.
Further, the refrigerant pipe 13E on the outlet side of the radiator 4 is branched in front of the outdoor expansion valve 6, and the branched refrigerant pipe (hereinafter referred to as a second bypass pipe) 13F is a solenoid valve 22 (for dehumidification) Is connected in communication with the refrigerant pipe 13B on the downstream side of the check valve 18. Furthermore, an evaporation pressure adjusting valve 70 is connected to the refrigerant pipe 13C on the outlet side of the heat absorber 9 on the refrigerant downstream side of the internal heat exchanger 19 and on the refrigerant upstream side from the junction with the refrigerant pipe 13D. . The solenoid valve 22 and the evaporation pressure regulating valve 70 are also connected to the output of the heat pump controller 32. Incidentally, the bypass pipe 45, the solenoid valve 30, and the bypass device 45 including the solenoid valve 40 in FIG. 1 of the embodiment described above are not provided. The other parts are the same as those in FIG.
The operation of the vehicle air conditioner 1 of this embodiment will be described with the above configuration. In this embodiment, the heat pump controller 32 switches and executes each operation mode of the heating mode, the dehumidifying heating mode, the internal cycle mode, the dehumidifying cooling mode, the cooling mode and the auxiliary heater sole mode (MAX cooling mode is present in this embodiment) do not do). The operation and the flow of the refrigerant when the heating mode, the dehumidifying and cooling mode, and the cooling mode are selected, and the auxiliary heater only mode are the same as those in the above-described embodiment (Embodiment 1), and thus the description thereof is omitted. However, in this embodiment (embodiment 3), the solenoid valve 22 is closed in the heating mode, the dehumidifying cooling mode and the cooling mode.
(13) Dehumidifying / heating mode of vehicle air conditioner 1 in FIG. 13 On the other hand, when the dehumidifying / heating mode is selected, the heat pump controller 32 opens the solenoid valve 21 (for heating) in this embodiment, Close for cooling. Also, the solenoid valve 22 (for dehumidification) is opened. Then, the compressor 2 is operated. The air conditioning controller 20 operates the blowers 15 and 27, and the air mix damper 28 is basically blown out from the indoor blower 27 and passes through the heat absorber 9 and all the air in the air flow passage 3 is heated by the heat exchange passage 3A. In the state of ventilating to the auxiliary heater 23 and the radiator 4, the air volume is also adjusted.
As a result, the high-temperature, high-pressure gas refrigerant discharged from the compressor 2 flows into the radiator 4 from the refrigerant pipe 13G. Since the air in the air flow passage 3 which has flowed into the heating heat exchange passage 3A is ventilated in the radiator 4, the air in the air flow passage 3 is heated by the high temperature refrigerant in the radiator 4, while the radiator is The refrigerant in 4 is cooled by the heat taken by the air and condenses and liquefies.
The refrigerant liquefied in the radiator 4 exits the radiator 4 and then reaches the outdoor expansion valve 6 through the refrigerant pipe 13E. The refrigerant flowing into the outdoor expansion valve 6 is decompressed there, and then flows into the outdoor heat exchanger 7. The refrigerant flowing into the outdoor heat exchanger 7 evaporates, and heat is pumped up from the outside air ventilated by the traveling or the outdoor blower 15. That is, the refrigerant circuit R is a heat pump. Then, the low temperature refrigerant leaving the outdoor heat exchanger 7 passes through the refrigerant pipe 13A, the solenoid valve 21 and the refrigerant pipe 13D, enters the accumulator 12 from the refrigerant pipe 13C, and is gas-liquid separated there, and then the gas refrigerant is the compressor 2 Repeat the cycle of sucking in
Further, a part of the condensed refrigerant flowing through the refrigerant pipe 13E through the radiator 4 is diverted, and passes through the solenoid valve 22 to the indoor expansion valve 8 through the internal heat exchanger 19 from the second bypass pipe 13F and the refrigerant pipe 13B. It will be. After the refrigerant is depressurized by the indoor expansion valve 8, the refrigerant flows into the heat absorber 9 and evaporates. At this time, the moisture in the air blown out from the indoor blower 27 condenses and adheres to the heat sink 9, so that the air is cooled and dehumidified.
The refrigerant evaporated by the heat absorber 9 passes through the internal heat exchanger 19 and the evaporation pressure adjusting valve 70 sequentially, joins with the refrigerant from the refrigerant pipe 13D in the refrigerant pipe 13C, and then passes through the accumulator 12 and is sucked into the compressor 2 repeat. The air dehumidified by the heat absorber 9 is reheated in the process of passing through the radiator 4, whereby dehumidifying and heating of the vehicle interior is performed.
The air conditioning controller 20 transmits the target heater temperature TCO (target value of the heating temperature TH) calculated from the target outlet temperature TAO to the heat pump controller 32. The heat pump controller 32 calculates a target radiator pressure PCO (a target value of the radiator pressure PCI) from the target heater temperature TCO, and the refrigerant of the radiator 4 detected by the target radiator pressure PCO and the radiator pressure sensor 47 The rotation speed NC of the compressor 2 is controlled based on the pressure (radiator pressure PCI, high pressure of the refrigerant circuit R), and heating by the radiator 4 is controlled. Further, the heat pump controller 32 controls the degree of opening of the outdoor expansion valve 6 based on the temperature Te of the heat absorber 9 detected by the heat absorber temperature sensor 48 and the target heat absorber temperature TEO transmitted from the air conditioning controller 20. Further, the heat pump controller 32 opens the evaporation pressure control valve 70 (enlarges the flow path) / closes (a small amount of refrigerant flows) based on the temperature Te of the heat absorber 9 detected by the heat absorber temperature sensor 48. Prevent the problem of freezing due to too low temperature.
(14) Internal cycle mode of vehicle air conditioner 1 in FIG. 13 In internal cycle mode, the heat pump controller 32 fully closes the outdoor expansion valve 6 in the dehumidifying and heating mode (fully closed position), Close the solenoid valve 21. By closing the outdoor expansion valve 6 and the solenoid valve 21, the inflow of the refrigerant to the outdoor heat exchanger 7 and the outflow of the refrigerant from the outdoor heat exchanger 7 are prevented, so the radiator 4 The condensed refrigerant flowing through the refrigerant pipe 13E passes through the solenoid valve 22 and all flows to the second bypass pipe 13F. Then, the refrigerant flowing through the second bypass pipe 13F passes from the refrigerant pipe 13B to the indoor expansion valve 8 through the internal heat exchanger 19. After the refrigerant is depressurized by the indoor expansion valve 8, the refrigerant flows into the heat absorber 9 and evaporates. At this time, the moisture in the air blown out from the indoor blower 27 condenses and adheres to the heat sink 9, so that the air is cooled and dehumidified.
The refrigerant evaporated by the heat absorber 9 flows through the refrigerant pipe 13C sequentially through the internal heat exchanger 19 and the evaporation pressure adjusting valve 70, and repeats the circulation sucked into the compressor 2 through the accumulator 12. Since the air dehumidified by the heat absorber 9 is reheated in the process of passing through the radiator 4, this means that dehumidifying and heating of the passenger compartment is performed, but in this internal cycle mode, the air flow on the indoor side Since the refrigerant is circulated between the radiator 4 (heat radiation) and the heat absorber 9 (heat absorption) in the passage 3, heating of heat from the outside air is not performed, and heating for the power consumption of the compressor 2 is performed. Ability is demonstrated. Since the whole amount of the refrigerant flows through the heat absorber 9 which exerts the dehumidifying action, the dehumidifying ability is higher than the dehumidifying and heating mode, but the heating ability is lowered.
The air conditioning controller 20 transmits the target heater temperature TCO (target value of the heating temperature TH) calculated from the target blowing temperature TAO to the heat pump controller 32. The heat pump controller 32 calculates a target radiator pressure PCO (target value of the radiator pressure PCI) from the transmitted target heater temperature TCO, and the target radiator pressure PCO and the radiator 4 detected by the radiator pressure sensor 47 The rotation speed NC of the compressor 2 is controlled based on the refrigerant pressure (the radiator pressure PCI, the high pressure of the refrigerant circuit R), and the heating by the radiator 4 is controlled.
And also in the case of this embodiment, the frosting determination of the outdoor heat exchanger 7 of (11) and the control of the compressor 2 etc. described above and the natural defrosting determination control of the outdoor heat exchanger 7 of (12) By performing this, it is possible to avoid unnecessary defrosting while suppressing a decrease in operating efficiency accompanying frost formation of the outdoor heat exchanger 7 while heating and air-conditioning the vehicle interior comfortably. However, the operation modes other than the heating mode in step S33 of FIG. 8 in the case of this embodiment are the dehumidifying and cooling mode and the cooling mode, which are operation modes in which the outdoor heat exchanger 7 does not absorb the refrigerant.
The numerical values and the like shown in the respective embodiments are not limited to them as described above, and should be appropriately set in accordance with the apparatus to be applied. Further, the auxiliary heating device is not limited to the auxiliary heater 23 shown in the embodiment, and a heat medium circulation circuit which heats the air in the air flow passage 3 by circulating a heat medium heated by the heater and an engine You may utilize the heater core etc. which circulate the heated radiator water.

1 Vehicle air conditioner 2 Compressor 3 Air flow passage 4 Radiator 6 Outdoor expansion valve 7 Outdoor heat exchanger 8 Indoor expansion valve 9 Heat sink 10 HVAC unit 11 Control device 20 Air conditioning controller 23 Auxiliary heater (auxiliary heating device)
27 Indoor blower (blower fan)
28 air mix damper 32 heat pump controller 33 outside temperature sensor 53 air conditioning control unit 54 outdoor heat exchanger temperature sensor 56 outdoor heat exchanger pressure sensor 65 vehicle communication bus 75 battery

Claims (7)

1. A compressor for compressing a refrigerant,
   An air flow passage through which air supplied to the vehicle compartment flows;
   A radiator for radiating the refrigerant and heating the air supplied from the air flow passage to the vehicle compartment;
   An outdoor heat exchanger provided outside the vehicle for absorbing heat from the refrigerant;
   Equipped with a control unit,
   The controller dissipates at least the refrigerant discharged from the compressor by the radiator, decompresses the dissipated refrigerant, and heats the vehicle interior by absorbing heat by the outdoor heat exchanger In a vehicle air conditioner performing
   The control device determines the progress of frost formation on the outdoor heat exchanger, and when it is determined that defrosting is necessary, the outdoor heat exchanger is satisfied when a predetermined defrost permission condition is satisfied. As well as defrosting
   After defrosting of the outdoor heat exchanger is determined to be necessary, if a predetermined natural defrosting condition is satisfied before defrosting, the outdoor heat exchanger is not defrosted. Air conditioner for vehicles.
2. The natural defrosting condition is
   The outside air temperature Tam is equal to or higher than a predetermined value Tam1, and the refrigerant evaporation temperature TXO of the outdoor heat exchanger is equal to or higher than an outside air temperature Tam-predetermined value β.
   The integrated value of the time during which the outside air temperature Tam is equal to or higher than the predetermined value Tam2 is equal to or longer than a predetermined time t3 while the vehicle is stopped.
   During the stop of the vehicle, the outside air temperature Tam becomes equal to or higher than the predetermined value Tam2, and the integral value obtained from the difference and the elapsed time becomes equal to or higher than the predetermined value X1.
   A predetermined period t4 or more has elapsed since the vehicle stopped.
   Selecting an operation mode in which the refrigerant is not absorbed by the outdoor heat exchanger;
   The vehicle air conditioner according to claim 1, characterized in that any one or a combination thereof or all of them.
3. The control device determines the non-adherent refrigerant evaporation temperature TXO of the outdoor heat exchanger when the refrigerant evaporation temperature TXO of the outdoor heat exchanger is lower than the refrigerant evaporation temperature TXObase of the outdoor heat exchanger at the time of no frosting. Refrigerant evaporation pressure of the outdoor heat exchanger based on the difference ΔTXO = TXObase-TXO with the refrigerant evaporation temperature TXObase of the outdoor heat exchanger at the time of frost, or when the refrigerant evaporation pressure PXO of the outdoor heat exchanger does not frost. Based on the difference ΔPXO = PXObase−PXO between the refrigerant evaporation pressure PKO of the outdoor heat exchanger and the refrigerant evaporation pressure PXObase of the outdoor heat exchanger at the time of no frost when the temperature is lower than PXObase, the outdoor heat exchanger can The air conditioning apparatus for a vehicle according to claim 1 or 2, wherein a progress state of frost formation is determined.
4. The control device is a refrigerant evaporation temperature TXObase of the outdoor heat exchanger at the time of the non-frosted state, or a refrigerant of the outdoor heat exchanger at the time of the non-frosted state based on the environmental condition and / or the index indicating the operating condition. The air conditioning apparatus for a vehicle according to claim 3, wherein the evaporation pressure P Xobase is estimated.
5. The compressor is driven by a battery mounted on a vehicle, and
   The defrosting permission condition is that there is no air conditioning request for the vehicle interior, and that the battery is being charged or the remaining amount of the battery is equal to or more than a predetermined value. The air conditioning apparatus for vehicles in any one of 4.
6. The control device includes an air conditioning controller connected to an air conditioning operation unit for performing an air conditioning setting operation of the vehicle compartment, and a heat pump controller for controlling the operation of the compressor, and the air conditioning controller and the heat pump controller Send and receive information via the vehicle communication bus,
   When the heat pump controller determines that defrosting of the outdoor heat exchanger is necessary, the heat pump controller sets a predetermined defrost request flag, and when the air conditioning controller sets the predetermined defrost permission flag, the outdoor heat exchanger After the defrost request flag is set and the natural defrost condition is satisfied, the defrost request flag is also reset.
   The air conditioning controller determines whether the defrosting permission condition is satisfied when the defrosting request flag is set by the heat pump controller, and sets the defrosting permission flag when the defrosting permission condition is satisfied. The air conditioning apparatus for vehicles according to any one of claims 1 to 5, characterized in that:
7. The air conditioning controller or the heat pump controller determines whether the natural defrosting condition is satisfied or not.
   The air conditioner for a vehicle according to claim 6, wherein when the air conditioning controller makes a determination, the heat pump controller is notified that the natural defrosting condition is satisfied.

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