JP5310323B2 - Control method for vehicle air conditioner - Google Patents

Description

  The present invention relates to a control method for a vehicle air conditioner that uses a compressor to send a refrigerant to a heat exchanger and performs heating by a heat pump cycle in a passenger compartment.

  Conventionally, the vehicle air conditioner described in Patent Document 1 is known. In this Patent Document 1, a heating heat exchanger (indoor condenser) is provided downstream of a hot water heat exchanger (heater core), and an air mix door is provided in each of the hot water heat exchanger and the heating heat exchanger. Yes.

  Specifically, the invention of Patent Document 1 does not fog the windshield when switching from cooling operation to heating operation, and even when air is passed through the heat exchanger for hot water when the engine cooling water temperature is low, It is an object of the present invention to provide a vehicle air conditioner that can effectively use the heat of air after passing through a hot water heat exchanger without lowering the temperature of the blown air.

  Therefore, in Patent Document 1, a cooling heat exchanger (evaporator), an air mix door for a hot water heat exchanger and a hot water heat exchanger, and an air for a heating heat exchanger and a heating heat exchanger are provided in a duct. Since each is arranged in the order of the mix door, the moisture can be gradually reduced and the windshield is not fogged.

  Even if the temperature of the engine cooling water is low and the temperature of the air after passing through the heat exchanger for hot water is low, the temperature of the air blown into the passenger compartment increases because the temperature is finally increased by the heat exchanger for heating. Yes. In addition, by disposing a heating heat exchanger downstream of the hot water heat exchanger, the heating water heat source is heated to some extent and then heated to a high temperature by the heating heat exchanger. Heating load of the heat exchanger for heating is reduced by effectively utilizing even the slight heat of the air after the ventilation of the exchanger.

Japanese Patent Laid-Open No. 5-96931

  However, in Patent Document 1, each of the hot water heat exchanger and the heating heat exchanger requires a dedicated air mix door, which increases the number of air mix means and causes an increase in cost. There is a problem that the size of the air-conditioning system for a vehicle becomes large.

  In view of the above problems, the present invention is not limited to the above-described problem, even if the hot water heat exchanger and the heating heat exchanger are arranged in the same air path, and a common air mixing means is provided upstream of the hot water heat exchanger. It is an object of the present invention to provide an air conditioner using a heat pump with excellent temperature control characteristics that can reduce discomfort due to a temperature drop.

  Descriptions of patent documents listed as prior art can be introduced or incorporated by reference as explanations of technical elements described in this specification.

In order to achieve the above object, the present invention employs the following technical means. That is, in the invention described in claim 1, between the indoor heat exchanger (18 and 19) comprising the cooling heat exchanger (18) and the heating heat exchanger (19) and the outdoor heat exchanger (15). COOL having a large cooling capacity so that the air blowing temperature of the blower (3) is equal to the target air temperature (TAO) obtained from the set temperature (Tset). A hot water heat exchanger that performs cycle operation and HOT cycle operation that is heating operation by a heat pump cycle, and is disposed in the same air path as the heating heat exchanger (19) and uses waste heat of cooling water ( 32) and the mixed state of the air in the same air path passing through the hot water heat exchanger (32) and the heating heat exchanger (19) and the cold air having passed through the cooling heat exchanger (18). , Heat for hot water In a control method for a vehicle air conditioner that includes a common air mix means (38) in the exchanger (32) and the heating heat exchanger (19), and performs the heating operation by the hot water heating cycle, the COOL cycle In the heating operation by the hot water heating cycle, the cold air that does not pass through the hot water heat exchanger (32) and the hot water heat exchanger (32) are determined so that the temperature of the heating heat exchanger (19) is determined to be low. The mixing ratio by the air mixing means (38) with the passing air is controlled to the heating side where the mixing ratio of the cold air is small, and the air is blown into the vehicle interior by the blower from the selected outlet , and the heat exchanger for heating (19) The refrigerant pressure value is used to calculate the temperature of the heater, and the temperature of the heating heat exchanger (19) is calculated with a delay in the change of the refrigerant pressure value, and the cycle of the COOL cycle operation and the HOT cycle operation is cut off. When changing the temperature of the heating heat exchanger without remembering delay to a change in the refrigerant pressure value (19) is characterized in that it is computed.

According to this invention, the heat exchanger for warm water and the heat exchanger for heating can be arranged in the same air path, and a common air mix door can be provided. Further, as the temperature of the heating heat exchanger (19) is determined to be lower, the air temperature is made closer to the target air temperature (TAO) by correcting the opening of the air mix means (38) to the heating side. Can do. Normally, in the heating operation by the heat pump cycle, the heating heat exchanger (19) is heated at a high temperature. For example, when the COOL cycle and the hot water heating cycle are used in winter, the heat exchange for heating is performed. Since the temperature of the heat exchanger (19) is lowered, even if the temperature of the cooling water temperature and the temperature of the heat exchanger for hot water (32) are high, the temperature of the blower is lowered due to the low temperature of the heat exchanger for heating (19). End up. In such a case, accurate temperature control can be realized by correcting the air mix means (38) to the heating side.
In addition, the refrigerant pressure value is used for calculating the temperature of the heating heat exchanger (19), and the temperature of the heating heat exchanger (19) is calculated with a delay in the change of the refrigerant pressure value. The frequent operation of the means (38) is suppressed, and the durability can be improved. Note that it is advantageous in terms of cost and space to use the existing refrigerant pressure to calculate the temperature of the heating heat exchanger (19). However, the refrigerant pressure varies depending on whether the compressor (14) is turned on or off. When the refrigerant pressure value is reflected in the control of the air mix means (38) as it is, it is recognized that the temperature of the heating heat exchanger (19) has frequently changed, and the actuator of the air mix means (38) is frequently Operates and decreases durability. Therefore, the durability of the air mix means (38) is improved by delaying the change in the refrigerant pressure value and calculating the temperature of the heating heat exchanger (19).
Further, when switching between the COOL cycle operation and the HOT cycle operation cycle, the temperature of the heating heat exchanger (19) is calculated without delaying the change in the refrigerant pressure value. Thereby, when the cycle change is made, if the sudden change in the refrigerant pressure is not reflected in the control of the air mix means (38), the refrigerant pressure is changed at the cycle change in consideration of the occurrence of the blowing temperature fluctuation at the cycle change. By not delaying the change in value, it is possible to prevent fluctuations in the blowing temperature.

  In invention of Claim 2, the opening degree of the air mix means (38) which determines the mixing ratio by an air mix means (38) is changed from the heat exchanger for hot water (32) and the heat exchanger for heating (19). The opening degree of the air mix means (38) is calculated so that the opening degree moves to the heating side as the heater temperature which is the temperature of the heater (19 and 32) becomes lower, and the heater temperature is the heat exchange for heating. The cooler the air that does not pass through the hot water heat exchanger (32), the lower the temperature of the heat exchanger (19), the lower the temperature of the heat exchanger (19) that is judged to be lower. The mixing ratio by the air mixing means (38) with the air passing through the hot water heat exchanger (32) is controlled to the heating side where the mixing ratio of the cold air is small.

  According to this invention, the mixing ratio of the air mix means (38) is determined by the opening degree of the air mix means (38), and the heater comprising the hot water heat exchanger (32) and the heating heat exchanger (19). Since the opening degree moves to the heating side as the heater temperature of (19 and 32) decreases, the problem that the blowout temperature decreases due to the low temperature of the heating heat exchanger (19), This can be solved by improving the calculation method of the opening degree of the air mix means (38).

In the third aspect of the present invention, when the air outlet mode is selected according to at least the target air outlet temperature (TAO) and the air outlet mode is the face mode and the COOL cycle is selected, the cooling water is selected. When it is determined that the blowing temperature of the blown air is lower than the target blowing temperature (TAO) due to the drop in temperature or the temperature of the heating heat exchanger (19), the blowing air is lower than the target blowing temperature (TAO). Compared to when it is determined that the blowout temperature is not low, the blower volume of the blower (3) is reduced.

  According to the present invention, when it is determined that the outlet temperature is lower than the target outlet temperature (TAO) when the outlet is in face mode and the COOL cycle is selected, the outlet is lower than the target outlet temperature (TAO). Compared to when it is determined that the temperature is not low, the amount of air blown from the blower (3) is reduced, so that it is possible to prevent the passenger from feeling chilly.

In the invention according to claim 4 , the target pressure (PDO) at which the refrigerant pressure becomes the target value of the refrigerant pressure in order to make the blowing temperature of the blown air by the blower (3) the target blowing temperature (TAO). Heat for heating to become the target blow temperature (TAO), the air flow rate or blower voltage of the blower (3), and the intake air temperature of the heating heat exchanger (19) in the calculation of the target pressure (PDO) While using the exchanger inlet temperature, the heating heat exchanger inlet temperature is calculated using the cooling water temperature when the cooling water is flowing through the hot water heat exchanger (32), and the hot water heat exchanger (32 ) Is calculated using the evaporator temperature, which is the temperature of the cooling heat exchanger (18) when the cooling water is not flowing.

  According to this invention, the heating heat exchanger inlet temperature is set to the cooling water temperature when the cooling water is flowing through the hot water heat exchanger (32), and the cooling water is supplied to the hot water heat exchanger (32). When is not flowing, by calculating the target pressure (PDO) as the evaporator temperature, the blowing temperature can be brought close to the target blowing temperature (TAO) with high accuracy. Moreover, it is not necessary to provide a special suction temperature sensor in the heating heat exchanger (19).

In the invention according to claim 5 , the air mixing means (38) is a single air mixing means (38) disposed upstream of the hot water heat exchanger (32) and the heating heat exchanger (19). ).

  According to the present invention, it is only necessary to control the single air mixing means (38), and the control becomes easy.

In the invention according to claim 6 , when the cooling water is flowing, the heating heat exchanger inlet temperature is calculated using the cooling water temperature and the evaporator temperature correction value which is a function value of the evaporator temperature (TE). It is characterized by that.

  According to this invention, the heat exchanger inlet temperature for heating can be obtained more accurately using the evaporator temperature correction value. As a result, the temperature of the conditioned air blown into the passenger compartment can be brought closer to the target temperature (TAO) more accurately.

  In addition, the code | symbol in the parenthesis as described in a claim and said each means is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

It is the whole schematic diagram at the time of COOL cycle of the air conditioner for electric vehicles used for a 1st embodiment of the present invention. It is a whole schematic diagram at the time of the HOT cycle of the air conditioner for electric vehicles used for the said embodiment. It is a whole schematic diagram at the time of DRY EVA cycle of the air conditioner for electric vehicles used for the above-mentioned embodiment. It is a whole schematic diagram at the time of DRY ALL cycle of the air conditioner for electric vehicles used for the above-mentioned embodiment. It is a solenoid valve action table | surface which shows how an air-conditioner control apparatus controls each solenoid valve in each said cycle in the said embodiment. It is a block diagram which shows the connection relation of the air-conditioner control apparatus and main various sensors etc. in the said embodiment. It is the flowchart which showed the basic air-conditioning control processing by the air-conditioner control apparatus in the said embodiment. It is a flowchart which shows the detail of the cycle selection in the said embodiment. It is a detailed flowchart for the blower voltage determination in the said embodiment. It is a characteristic view for determining a blower outlet mode from target blow temperature used in the above-mentioned embodiment. It is a flowchart which calculates the opening degree of the air mix door in the said embodiment. It is a flowchart explaining the step which determines the compressor rotation speed in the said embodiment. It is a map for calculating a temporary target pressure from the heat exchanger target temperature for heating in the said embodiment, and the inlet temperature of the heat exchanger for heating. It is a map which shows the relationship in the said embodiment, the deviation change rate, and the compressor rotation speed change amount for the heating by a heat pump cycle. It is a map which shows the relationship in the said embodiment, the deviation change rate, and the compressor rotation speed variation | change_quantity for the cooling by a COOL cycle. It is a flowchart explaining the step which determines the compressor rotation speed in 2nd Embodiment of this invention.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS. In the first embodiment, a vapor compression refrigerator is applied to an air conditioner for a hybrid vehicle.

  A hybrid vehicle is an engine (E / G) that constitutes a traveling internal combustion engine that explodes and burns liquid fuel such as gasoline to generate power, a traveling assist motor generator having a traveling assist motor function and a generator function, Engine electronic control device (engine ECU) for controlling the fuel supply amount and ignition timing to the engine, battery for supplying electric power to the motor generator, engine electronic control device, etc. Control of the motor generator and a continuously variable transmission And a hybrid electronic control unit that controls the electromagnetic clutch and outputs a control signal to the engine electronic control unit.

  The hybrid electronic control device has a function of controlling drive switching of which driving force of the motor generator and the engine is transmitted to the drive wheels, and a function of controlling charging / discharging of the battery.

Specifically, the following control is performed.
(1) When the vehicle is stopped, the engine is basically stopped.
(2) During traveling, the driving force generated by the engine is transmitted to the drive wheels except during deceleration. During deceleration, the engine is stopped, the motor generator generates power, and the battery is charged.
(3) When the driving load such as starting, accelerating, climbing, and traveling at high speed is heavy, the motor generator is caused to function as an electric motor, and in addition to the driving force generated in the engine, the driving generated in the motor generator Transmits force to the drive wheels.
(4) When the remaining charge amount of the battery becomes equal to or less than the charge start target value, the engine power is transmitted to the motor generator, and the motor generator is operated as a generator to charge the battery.
(5) When the remaining amount of charge of the battery becomes equal to or less than the charge start target value when the vehicle is stopped, a command to start the engine is issued to the engine electronic control device, and the engine power is generated by the electric power generation. Communicate to the machine.

  FIG. 1 is an overall schematic diagram at the time of a COOL cycle of an air conditioner for an electric vehicle serving as a vehicle air conditioner in the first embodiment. An electric vehicle air conditioner 1 using an accumulator refrigeration cycle includes a duct 2 that guides blown air into the vehicle interior, a blower 3 that introduces air into the duct 2 and sends the air into the vehicle interior, and an air conditioner control device 5 (described later). 6).

  The blower 3 in FIG. 1 includes a blower case (not shown), a centrifugal fan 3b, and a blower motor 3c. The rotational speed of the blower motor 3c is determined according to the voltage applied to the blower motor 3c. The voltage applied to the blower motor 3 c is controlled based on a control signal from the air conditioner control device 5.

  As is well known, a blower case (not shown) of the blower 3 is formed with an interior air introduction port (not shown) for introducing vehicle interior air (inside air) and an outside air introduction port (not shown) for introducing vehicle exterior air (outside air). In addition, there is provided an inside / outside air switching damper that constitutes an inside / outside air switching means (not shown) that adjusts the opening ratio between the inside air introduction port and the outside air introduction port.

  As is well known, the downstream end of the duct 2 (upper side in FIG. 1) includes a defroster outlet (not shown) that discharges the blowing air toward the windshield of the vehicle, a face outlet that discharges the blowing air toward the upper body of the occupant, It is communicated with a foot outlet that discharges air to the feet of passengers.

  The refrigeration cycle includes a compressor 14, an outdoor heat exchanger 15, a cooling decompression device 16, a heating decompression device 17, a cooling heat exchanger (also referred to as an evaporator) 18, a heating heat exchanger 19, an accumulator 21, and a flow path. Switching means (described later) is provided.

  The compressor 14 is driven by a built-in electric motor 14a. The rotational speed of the electric motor 14a is determined according to the frequency that is variably controlled by an inverter (not shown). Therefore, the refrigerant discharge flow rate of the compressor 14 changes according to the rotational speed of the electric motor 14a.

  The outdoor heat exchanger 15 is disposed outside the passenger compartment and performs heat exchange between the outside air and the refrigerant. The outdoor heat exchanger 15 receives air from the outdoor fan 24, functions as an evaporator during heating operation, and functions as a condenser during cooling operation. .

  The refrigerant liquefied for cooling is introduced into the cooling decompression device (temperature-sensitive expansion valve) 16 shown in FIG. 1 and rapidly expands under reduced pressure to form a low-temperature and low-pressure mist. The low-temperature and low-pressure mist refrigerant is supplied to the cooling heat exchanger 18. The heating decompression device (heating restriction) 17 decompresses and expands the refrigerant supplied to the outdoor heat exchanger 15 during the heating operation.

  The cooling heat exchanger 18 functions as an evaporator and is disposed in the duct 2. The cooling heat exchanger 18 cools the air passing through the cooling heat exchanger 18 by performing heat exchange between the low-temperature and low-pressure refrigerant decompressed and expanded by the cooling decompression device 16 and the air.

  The heating heat exchanger 19 functions as a condenser. The heating heat exchanger 19 is disposed downstream (downwind) of the cooling heat exchanger 18 in the duct 2, and the high-temperature and high-pressure refrigerant compressed by the compressor 14 and air. By performing heat exchange, the air passing through the heat exchanger 19 for heating is heated.

  The water pump 31 supplies hot water composed of engine cooling water to a hot water heat exchanger (also referred to as a heater core) 32. The hot water heat exchanger 32 functions as a heater together with the heating heat exchanger 19.

  As is well known, the air mix door (A / M) 38, which constitutes the air mix means, adjusts the mixing ratio between the cool air from the cooling heat exchanger 18 and the warm air from the heating heat exchanger 19 and the like (heater). Control. The accumulator 21 temporarily stores excess refrigerant in the refrigeration cycle and sends out only the gas-phase refrigerant to prevent the liquid refrigerant from being sucked into the compressor 14.

  Heating three-way valve (HTMV) 25a, high pressure solenoid valve (HPMV) 25b, low pressure solenoid valve (LPMV) 25c, dehumidification solenoid valve (DHMV) 25d, heat exchange (heat exchange) shut valve (HSMV) 25e, first check valve 27 and the second check valve 28 form a flow path switching means.

  The flow path switching means 25a, 25b, 25c, 25d, 25e, 27, and 28 are used for the refrigerant flow at the COOL cycle, HOT cycle, DRY EVA cycle, and DRY ALL cycle, which are the types of operation, respectively. The direction is switched.

  Hot water from the engine 30 is supplied to the heater core 32 by a water pump 31. Reference numeral 35 denotes a refrigerant suction temperature sensor for measuring the refrigerant suction temperature T35. In addition, arrows 40, 41, 42, 43, and 44 indicate the direction in which the refrigerant flows.

  The refrigerant pressure sensor 50PRE detects the high pressure of the refrigerant upstream from the heating heat exchanger 19 (the discharge pressure of the compressor 14) PRE. The refrigerant suction temperature sensor 35 is provided on the downstream side of the refrigerant flow in the outdoor heat exchanger 15 and detects a refrigerant suction temperature T35. Moreover, with respect to the outdoor heat exchanger 15, the cooling heat exchanger 18 and the heating heat exchanger 19 form an indoor heat exchanger (18 and 19).

(COOL cycle)
In the COOL cycle in which there is no heating performance and the dehumidifying capacity is at a high level, as shown in FIG. 1, the refrigerant discharged from the compressor 14 is heated from the heat exchanger 19 to the heating three-way valve 21 to the outdoor heat exchange. The flow path switching means 25a, 25b, 25c, 25d so that the flow flows in the order of the heater 15 → the high pressure solenoid valve 25b → the first check valve 27 → the cooling pressure reducing device 16 → the cooling heat exchanger 18 → the accumulator 21 → the compressor 14. , 25e, 27, and 28 are switched. The flow of refrigerant during this operation is indicated by arrows 40, 41, 42, 43, and 44 in the figure.

  As a result, heat is released from the outdoor heat exchanger 15 functioning as a condenser to the outside, and heat is absorbed from the cooling heat exchanger (functioning as an evaporator) 18. At this time, the heating heat exchanger 19 also generates heat, but the position of the air mix door 38 can control the amount of heat exchange with the vehicle interior air.

(HOT cycle)
FIG. 2 is an overall schematic diagram at the time of a HOT cycle of an air conditioner for an electric vehicle serving as a vehicle air conditioner in the first embodiment. At the time of operation by the HOT cycle, which is the operation with high heating performance and no dehumidification capability, as shown in FIG. 2, the refrigerant discharged from the compressor 14 is heated by the heat exchanger 19 for heating → the three-way valve for heating 21 → the heating. Pressure reducing device 17 → heat exchanger valve 25e → outdoor heat exchanger 15 → low pressure solenoid valve 25c → second check valve 28 → accumulator 21 → compressor 14 in this order.

  The flow of the refrigerant during this operation is indicated by arrows 40, 41, 45, 42a, 46, and 47 in the figure. When the outdoor air is extremely low, heating by the HOT cycle is inefficient, so the engine is operated in the above-described COOL cycle, the temperature of the engine cooling water (warm water) is increased, and the heat exchanger 32 for hot water is The vehicle interior is heated by heat.

(DRY EVA cycle)
FIG. 3 is an overall schematic diagram at the time of the DRY EVA cycle of the air conditioner for an electric vehicle in the first embodiment. In this embodiment, the DRY EVA cycle is selected when the heating capacity is low and the vehicle interior is dehumidified at a medium level.

  In this DRY EVA cycle, as shown in FIG. 3, the refrigerant discharged from the compressor 14 is heated from the heat exchanger 19 → the heating three-way valve 25 a → the heating decompressor 17 → the dehumidifying electromagnetic valve 25 d → the cooling heat exchanger 18. → Accumulator 21 → Compressor 14 flows in this order.

  The flow of the refrigerant during this operation is indicated by arrows 40, 41, 45, 47, and 48 in the figure. In this DRY EVA cycle, the outdoor heat exchanger 15 is not used but the cooling heat exchanger (evaporator) 18 is used, and the heating performance is low and the dehumidifying capacity is medium level.

(DRY ALL cycle)
FIG. 4 is an overall schematic diagram of the air conditioner for an electric vehicle in the first embodiment during a DRY ALL cycle. In this embodiment, the DRY ALL cycle is selected and executed when the heating capacity is medium and the vehicle interior is dehumidified at a low level. In this DRY ALL cycle, both the cooling heat exchanger (evaporator) 18 and the outdoor heat exchanger 15 are used.

  In this DRY ALL cycle, as shown in FIG. 4, the refrigerant discharged from the compressor 14 is heated from the heat exchanger 19 → the heating three-way valve 25 a → the heating decompressor 17 → the heat exchanger valve 25 e → the outdoor heat exchanger 15. It flows in the order of the low pressure solenoid valve 25c, the second check valve 28, the accumulator 21, and the compressor 14.

  At the same time, the refrigerant flows in the order of the heating decompressor 17 → the dehumidifying electromagnetic valve 25 d → the cooling heat exchanger 18 → the accumulator 21 → the compressor 14. The refrigerant flow during this operation is indicated by arrows 40, 41, 45, 42a, 46, 47, 49, 48 in the figure.

  The air conditioner control device 5 (FIG. 6) not shown in FIGS. 1 to 4 incorporates a microcomputer (not shown). FIG. 5 is an electromagnetic valve operation table showing how the air conditioner control device 5 controls the electromagnetic valves 25a to 25e in each cycle.

  FIG. 6 is a block diagram showing a connection relationship between the air conditioner control device 5 and various sensors. The sensors detect an inside air sensor 50Tr that detects the room temperature Tr, an outside air sensor 50Tam that detects the outside air temperature Tam, a solar radiation sensor 50Ts that detects the amount of solar radiation Ts, and a suction side air temperature Tin of the heating heat exchanger 19 in FIG. An inlet temperature sensor 50Tin, a refrigerant pressure sensor 50PRE for detecting a high pressure of refrigerant (discharge pressure of the compressor 14) PRE upstream of the heating heat exchanger 19, and downstream of the refrigerant flow of the outdoor heat exchanger 15 in FIG. A refrigerant suction temperature sensor 35 (hereinafter, omitted) that is provided and detects the refrigerant suction temperature T35 is provided.

  In addition, the air conditioner control device 5 is based on the operation signal output from the air conditioner operation panel 51 and the detection signal from each of the above sensors, the blower 3, the inverter 52 for driving the compressor 14, the outdoor fan 24, the heating three-way valve 25a, Electric components such as the various electromagnetic valves 25b to 25e, the well-known inside / outside air switching damper 53, and the outlet switching damper 54 are energized and controlled. It should be noted that the inside / outside air switching damper 53 and the outlet switching damper 54 are actually energized from the air conditioner control device 5 to the actuator portions that drive these dampers.

  Further, the air conditioner control device 5, the hybrid electronic control device (not shown) and the engine electronic control device (not shown) can communicate with each other. In the first embodiment, communication is performed by data communication based on a predetermined protocol. doing.

  The air conditioner operation panel 51 has a manual switch (not shown) for manually switching the operation state of the refrigeration cycle to any one of the COOL cycle, HOT cycle, DRY EVA cycle, and DRY ALL cycle. A signal is input to the air conditioner control device 5.

  Further, the air conditioner operation panel 51 of FIG. 6 includes an air conditioner switch for instructing start and stop of the electric motor 14a built in the compressor 14 of FIG. 1, and a suction port changeover switch for switching the suction port mode in the manual mode. A temperature setting switch for setting the temperature in the passenger compartment to a desired set temperature Tset, an air volume switching switch for switching the air flow rate of the blower 3 in FIG. 1 in the manual mode, and an air outlet mode (not shown) are switched in the manual mode. For example, an air outlet changeover switch is provided.

FIG. 7 is a flowchart showing basic control processing by the air conditioner control device 5 (FIG. 6) of the first embodiment. In FIG. 7, the control starts when the ignition switch is turned on and power is supplied to the air conditioner control device 5.
(Pre-air conditioning judgment)
The air conditioner control device 5 shown in FIG. 6 constitutes a remote control device (not shown), which is a signal from the various sensors described above, signals from various operation members provided on the air conditioner operation panel 51, and operation means capable of remote operation. The vehicle interior is configured to be air-conditioned based on a signal from the portable device. When the vehicle continuously stops and no occupant is on board, the air conditioner control device 5 monitors the presence or absence of a pre-air conditioning request from the remote control device.

  Then, when there is a pre-air conditioning request from the remote control device (when there is a request for immediate air conditioning, or when it is time to start air conditioning based on the air conditioning request time transmitted and input in advance), the vehicle It is determined whether or not it is in a stopped state, and it is determined whether or not the power supply power is larger than the required power during pre-air conditioning operation.

  When it is confirmed that the vehicle is in a stopped state and the power supply power is larger than the pre-air conditioning required power, a pre-air conditioning flag is set to permit the execution of the pre-air conditioning (step S1).

(Initialization)
Next, each parameter in the air conditioner control device 5 of FIG. 6 is initialized (initialized) (step S2).

(Read switch signal)
Next, a switch signal or the like is read from the air conditioner operation panel 51 shown in FIG. 6 (step S3).

(Read sensor signal)
Next, signals from various sensors shown in FIG. 6 are read (step S4).

(TAO calculation basic control)
Next, based on the following formula 1 stored in the ROM, a target blowing temperature TAO of air blown into the passenger compartment is calculated (step S5).

(Formula 1) TAO = Kset × Tset−Kr × Tr−Kam × Tam−Ks × Ts + C
Here, Tset is the set temperature set by the temperature setting switch, Tr is the room temperature detected by the inside air sensor 50Tr, Tam is the outside air temperature detected by the outside air sensor 50Tam, and Ts is the amount of solar radiation detected by the solar sensor 50Ts. is there. Kset, Kr, Kam, and Ks are gains, and C is a constant for correction.

  Then, based on signals from the TAO and the various sensors, a control value of an actuator, which will be described later, of the air mix door 38 in FIG. 1, and a control value such as the rotational speed of the water pump 31 as is well known are calculated. .

(Cycle selection)
Next, the cycle to be operated is selected in step S6 in FIG. This step S6 is specifically performed based on FIG. FIG. 8 is a flowchart showing details of cycle selection in step S6 of FIG.

  In FIG. 8, when control is started, it is determined in step S30 whether or not the outside air temperature is lower than −3 ° C. If the outside air temperature is lower than −3 ° C., the performance of the heat pump is not sufficient, so that the COOL cycle is set in step S32. At this time, when the temperature of the engine cooling water (warm water) is low and the engine 30 in FIG. 1 is stopped, the engine 30 is started. If the outside air temperature is not lower than −3 ° C., it is determined in step S31 whether or not the air outlet mode in the automatic control is the face (FACE) mode.

  In the face mode, it is determined that “no heat pump cycle is necessary”, and a COOL cycle is set in step S32. If it is not the face mode, it is determined in step S33 whether there is a possibility of window fogging.

  This fogging determination of the window glass is known in Japanese Patent Application Laid-Open No. 2002-120545. The cloudiness determination will be briefly described. When RH25 is a comfortable humidity (relative humidity corresponding to 25 ° C.) of the relative humidity in the vehicle interior and RHW25 is a saturated absolute humidity equivalent to 25 ° C., RH25 and RHW25 can be calculated based on the following equations 2 and 3.

(Expression 2) RH25 = f (Tr) × RH / 100 (%)
However, RH is a relative humidity that is a detection value of a humidity sensor (not shown), and f (Tr) is a function of a room temperature Tr that is a detection value of the inside air sensor 50Tr in FIG.

(Formula 3) RHW25 = f (TWG) (%)
However, f (TWG) is a function of the window temperature TWG. This window temperature is expressed by a function of room temperature (Tr), solar radiation (Ts), outside air temperature (Tam), and vehicle speed (SPD). When it rains, window temperature (TWG) = outside air temperature (Tam). .

  In step S33 of FIG. 8, if the saturation absolute humidity RHW25 corresponding to 25 ° C. is greater than 100, it is determined that there is a possibility of window fogging. If there is no possibility of window fogging, heating without dehumidification (HOT cycle) with the highest heating efficiency is performed in step S38.

  If it is determined in step S33 that the saturation absolute humidity RHW25 corresponding to 25 ° C. is greater than 100 and there is a possibility of window fogging, the process proceeds to step S34, and the cooling water temperature (= the temperature of the hot water heat exchanger 32 in FIG. 1). ), It is determined whether there is a possibility that the heating heat exchanger 19 cannot sufficiently exchange heat with air. In FIG. 8, RHW25 is simply abbreviated as RHW.

  For this reason, in step S34, it is determined whether or not “heating heat exchanger target temperature−cooling water temperature” is higher than −3 ° C. and lower than + 3 ° C. When the heating heat exchanger target temperature and the cooling water temperature are close to each other and “heating heat exchanger target temperature−cooling water temperature” is higher than −3 ° C. and lower than + 3 ° C., the heating heat exchanger shown in FIG. The heat exchanger 19 determines that heat cannot be sufficiently exchanged (heat cannot be given to the air), and the process proceeds to step S35.

  In step S35, the air conditioner control device 5 in FIG. 6 requests an engine electronic control device (engine ECU) (not shown) to increase the engine speed by +500 rpm. In order to prevent the blowout temperature from being lowered when the engine speed is increased and the COOL cycle is switched in the subsequent steps, the cooling water temperature is raised.

  In step S34, the heating heat exchanger target temperature and the cooling water temperature are not close to each other, and “heating heat exchanger target temperature−cooling water temperature” is not higher than −3 ° C. or from + 3 ° C. If not, it is determined that the heat exchanger 19 for heating in FIG. 1 can sufficiently exchange heat with air, and the process proceeds to step S36.

  In this step S36, it is determined whether or not the difference between the heating heat exchanger target temperature of the heating heat exchanger 19 and the cooling water temperature (= temperature of the hot water heater 32) is lower than + 1 ° C. If the heating heat exchanger target temperature is higher than the cooling water temperature and the “heating heat exchanger target temperature−cooling water temperature” is not lower than + 1 ° C., the heating heat exchanger 19 sufficiently exchanges heat. Therefore, the process proceeds to step S37.

  In step S37, the evaporator temperature TE which is a measured value of the surface temperature of the cooling heat exchanger (evaporator) 18 of FIG. 1 is used. When “2 ° C.-evaporator temperature (denoted as 2-TE)” in step S37 is 2 <(2-TE), and (2-TE) is higher than 2 ° C., switching to a HOT cycle having no dehumidifying ability ( Step S38).

  When the above-mentioned 2-TE is higher than 1 ° C. and lower than 2 ° C. and satisfies the condition of 1 <(2-TE) ≦ 2, in step S39, the operation of the DRY ALL cycle (low dehumidifying capacity, during heating capacity) is performed. Switch to. If the 2-TE is 1 ° C. or lower, the operation is switched to the DRY EVA cycle (during the dehumidifying capacity and the heating capacity is small) in step S40.

  In step S36, when (heating heat exchanger target temperature−cooling water temperature) <1 is satisfied and the heating heat exchanger target temperature TAO HP is lower than the cooling water temperature, the heating heat exchanger 19 , Heat exchange is not possible. Therefore, at this time, it is determined in step S41 whether or not it is necessary to switch to the COOL cycle.

In step S41, the necessity of the cooler cycle is determined based on whether or not the possibility of window fogging is high. This is determined by whether or not the saturated absolute humidity RHW25 corresponding to 25 ° C. is 110 or more. If it is determined in step S41 that RHW25> 110 is not satisfied and the possibility of window fogging is not high, the process proceeds to step S37. If it is determined in step S41 that RHW25> 110 and there is a high possibility of window fogging, high dehumidification performance is obtained by switching to the COOL cycle in step S32.
(Blower voltage determination)
Next, in step S7 of FIG. 7, a blower voltage corresponding to the target blowing temperature TAO is determined from the characteristic diagram stored in the ROM. That is, the applied voltage to the blower motor 3c of the blower 3 of FIG. 2 is determined.

  FIG. 9 is a detailed flowchart for determining the blower voltage in step S7 of FIG. In FIG. 9, when the control starts, it is determined in step S110 whether the control of the blower 3 in FIG. 1 is in the auto mode. When the manual mode is selected instead of the auto mode, a voltage of 4 volts is applied to the blower motor 3c when the operation position is L0 in step S111.

  When the operation position is M1, a voltage of 6 volts is applied to the blower motor 3c. When the operation position is M2, a voltage of 8 volts is applied to the blower motor 3c. When the operation position is M3, a voltage of 10 volts is applied to the blower motor 3c. When the operation position is Hi, a blower voltage of 12 volts is applied to the blower motor 3c.

  If it is determined in step S110 that the control of the blower 3 in FIG. 1 is in the auto mode, a base blower that is an applied voltage to the blower motor 3c serving as a base is determined in step S112 in accordance with the target blowing temperature TAO. Determine the voltage.

  Next, in step S113, it is determined whether or not the air outlet is in face mode and is operated by a COOL cycle. In the case of the COOL cycle, in order to correct the blower voltage in step S114 depending on whether or not the blowing temperature from the heaters 32 and 19 in FIG. 1 is low with respect to the target blowing temperature TAO. The blower voltage correction amount during the COOL cycle is calculated. In the map used in step S114, the horizontal axis represents the difference between the higher one of the cooling water temperature and the temperature of the heating heat exchanger 19 and the target outlet temperature TAO.

  In step S116, the larger one of the difference voltage (volt) between the base blower voltage and the blower voltage correction amount and 4 volts is determined as the current blower voltage and applied to the blower motor 3c.

With this correction, when the cooling water temperature or the temperature of the heating heat exchanger 19 is low and the blowout temperature via the heaters 32 and 19 is low with respect to the target blowout temperature TAO, the blower voltage correction amount becomes negative. Since the blower voltage in step S116 of FIG. 9 applied to the blower 3 of FIG. 1 is increased and the chill of the occupant can be reduced.
(Suction port mode decision)
Next, in step S8 of FIG. 7, a suction port mode corresponding to the target outlet temperature TAO is determined from a characteristic diagram (not shown) stored in the ROM. Specifically, when the target blowing temperature TAO is high, the inside air circulation mode is selected, and when the target blowing temperature TAO is low, the outside air introduction mode is selected.
(Air outlet mode decision)
FIG. 10 is a characteristic diagram for determining the outlet mode from the target outlet temperature TAO stored in the ROM. In step S9 of FIG. 7, the outlet mode corresponding to the target outlet temperature TAO is determined from the characteristic diagram of FIG. Specifically, when the target blowout temperature TAO is high, the foot (FOOT) mode is selected from the map of FIG. 10, and as the target blowout temperature TAO decreases, the bi-level (B / L) mode and the face ( FACE) mode.
(SW calculation)
Next, in step S10 of FIG. 7, the opening degree SW of the air mix door 38 of FIG. 1 is calculated from the target blowing temperature TAO or the like. FIG. 11 is a flowchart for calculating the opening degree SW of the air mix door 38 of the first embodiment.

  In FIG. 11, when control is started, it is determined in step S50 whether indoor heating control is performed by a heat pump cycle. If any one of steps S38, S39, and S40 in FIG. 8 is selected, that is, if the selected cycle is indoor heating control by a heat pump cycle, the air mix in FIG. 2 is performed in step S54 in FIG. The door 38 is fixed to Max Hot (MAX HOT; the position of the air mix door 38 where substantially all the conditioned air passes through the heating heat exchanger 19).

  As a result, the temperature of the heating heat exchanger 19 is approximately equal to the temperature of the air blown into the passenger compartment, and the minimum necessary temperature of the heat exchanger 19 for heating is sufficient for the desired air temperature. Control becomes possible. In this power saving control, the blowout temperature is adjusted not by adjusting the blowout temperature by controlling the opening degree SW of the air mix door 38 but by controlling the temperature of the heat exchanger 19 for heating.

  Next, if it is not heating control by a heat pump cycle in step S50 of FIG. 11, the control water temperature TW used for control of the air mix door 38 is calculated in step S52. In this step S52, the control water temperature TW selects the higher one of the cooling water temperature and the heating heat exchanger target temperature, which is the target temperature of the heating heat exchanger 19, as the control water temperature TW.

  When the cooling water temperature increases with the operation of the engine 30 of FIG. 1 due to the acceleration of the vehicle or the decrease in the remaining battery level by the selection of the control water temperature TW, the control water temperature TW, and consequently the heat exchanger 19 for heating and the heat for hot water The temperature of the heater composed of the exchanger 32 also tends to increase. For this reason, since the denominator of the calculation formula of the opening degree SW of the air mix door 38 obtained in step S59 becomes large and the opening degree SW of the air mix door 38 becomes small, the position of the air mix door 38 moves to the cooling side.

  That is, when the cooling water temperature increases, the position of the air mix door 38 moves to the side opposite to the maximum hot position, and the cool air from the cooling heat exchanger (evaporator) 18 in FIG. It is mixed with warm air to regulate the temperature of the air blown into the room.

  Subsequent to step S52, in step S53, f (evaporator temperature) serving as an evaporator temperature correction value is calculated. The evaporator temperature correction value f (evaporator temperature) is obtained from the map described in step S53 of FIG. 11 as a function value of the evaporator temperature TE, which is the surface temperature of the cooling heat exchanger (evaporator) 18 of FIG. Note that “f” of f (evaporator temperature) represents a function.

  Next, in step S55, the temperature of the heating heat exchanger 19 is calculated from the refrigerant pressure. Since the temperature of the refrigerant increases as the pressure increases, the temperature f (PRE) of the heating heat exchanger 19 is obtained from the map in step S55 by using the refrigerant pressure PRE, which is the measurement value of the refrigerant pressure sensor 50PRE in FIG. Can be calculated. “F” represents a function, and the temperature of the heating heat exchanger 19 is obtained as a function value of the refrigerant pressure PRE.

  At this time, a time constant τ of 60 seconds is applied to the temperature f (PRE) of the heat exchanger 19 for heating. In other words, instead of handling the instantaneous value of the temperature f (PRE) of the heating heat exchanger 19 that fluctuates, a rounding operation with a time constant τ of 60 seconds is performed, and the rounded value is converted into that of the heating heat exchanger 19. The temperature is used for subsequent calculations.

  As a result, the value of the opening SW of the air mix door 38 obtained in step S59, which will be described later, does not fluctuate due to the refrigerant pressure fluctuation caused by turning the compressor 14 on and off (ON / OFF), and an air mix door actuator (not shown) is frequently used. Since it does not turn ON / OFF, it is possible to prevent a decrease in durability of the air mix door actuator.

  However, if a sudden change in refrigerant pressure is not reflected in the control of the air mix door 38 at the time of cycle switching, the blowout temperature fluctuation occurs at the time of cycle switching. Therefore, the time constant τ is set to 0 at the time of cycle switching. Therefore, fluctuations in the blowing temperature are prevented.

  Next, in step S56, it is determined whether or not the water pump 31 that sends engine cooling water to the hot water heat exchanger 32 of FIG. 1 is operating in the COOL cycle. If it is determined in step S56 that the operation cycle is a COOL cycle and the water pump 31 is operating, the process proceeds to step S57.

  In step S57, “f (PRE)” that is the temperature of the heating heat exchanger 19 is set to “(TW × 0.8) + f (evaporator temperature)” that is the downstream temperature of the hot water heat exchanger 32. The heater temperature added at each predetermined rate is calculated.

  Here, TW is the control water temperature obtained in step S52. Further, f (evaporator temperature) is the evaporator temperature correction value obtained in step S53. Moreover, f (PRE) calculated | required by step S55 is the temperature of the heat exchanger 19 for heating. The heater is a general term for the hot water heat exchanger 32 and the heating heat exchanger 19, and the temperature of the air that has passed through the hot water heat exchanger 32 and the heating heat exchanger 19 is determined by the heater. Temperature.

  The heater temperature is obtained by “0.8 × {(TW × 0.8) + f (evaporator)} + 0.2 × f (PRE)”.

  Thus, even when the temperature f (PRE) of the heating heat exchanger 19 is lowered during the COOL cycle and the temperature of the warm air heated by the hot water heat exchanger 32 is lowered, the temperature of the heating heat exchanger 19 is decreased. Is lower, the heater temperature calculated in step S57 becomes lower, and the denominator of the formula for calculating the opening degree SW of the air mix door 38 calculated in step S59 becomes smaller, so the opening degree SW becomes larger and the air mix door becomes larger. Since the opening degree of 38 moves to the heating side, the decrease in the air temperature by the heating heat exchanger 19 whose temperature has decreased is corrected, and the temperature of the blown air that matches the target blowing temperature TAO can be realized with high accuracy.

  In other words, in the heat pump cycle, the heating heat exchanger 19 is usually heated at a high temperature. However, when the hot water heating cycle is used in the COOL cycle in winter, the heating heat exchanger 19 in the heat pump cycle is used. Therefore, even if the temperature of the hot water (cooling water) is high, the blowing temperature is lowered due to the low temperature of the heat exchanger 19 for heating.

  For this reason, when it can be judged that the temperature of the heat exchanger 19 for heating is low, the blowout temperature can be brought close to the target blowout temperature TAO as much as possible by correcting the opening of the air mix door 38 to the heating side.

  Next, in Step S59, the opening degree SW of the air mix door (A / M) 38 is set to Step S59 in FIG. 11 using the heater temperature, the target blowing temperature TAO, and the evaporator temperature TE obtained in Step S57. Calculation is performed using the mathematical formula described.

  The denominator of this arithmetic expression is approximately the larger of the difference between the heater temperature and the evaporator temperature TE or 10 as the denominator. Further, the difference between TAO and evaporator temperature TE is defined as a numerator. Note that + 2 ° C. in the calculation formula of the opening degree SW in step S59 may be omitted and Formula 4 may be used.

(Formula 4) SW = {(TAO-TE) / MAX (10, heater temperature-TE)} × 100 (%)
As described above, when the cooling water temperature in step S52 increases with the acceleration of the vehicle or the operation of the engine 30 in FIG. 1 due to the decrease in the remaining battery level, the heater temperature obtained in step S57 increases. The denominator of the calculation formula for the opening degree SW of the air mix door 38 obtained in step S3 is increased, and the opening degree SW of the air mixing door 38 is reduced. For this reason, even if the cooling water temperature increases, the actual blowing temperature does not greatly deviate from the target blowing temperature TAO.

In step S56, if the cycle is not a COOL cycle or if the water pump 31 is not operating, the process proceeds to step S58, where the heater temperature is “(TW × 0.8) + f (evaporator)”. Is required.
(Determine compressor speed)
Next, the compressor rotation speed is determined in step S11 of FIG. FIG. 12 is a flowchart for explaining the step of determining the compressor speed in step S11 of FIG.

  In FIG. 12, when the control starts, it is determined in step S60 whether or not the target outlet temperature TAO is equal to or higher than the limit value of 47 ° C. The value of TAO = 47 ° C. is set to a value that most people can obtain a sufficient feeling of heating and is not excessively high.

  If the target blowing temperature TAO is relatively low and lower than 47 ° C., the target blowing temperature TAO is set to the heating heat exchanger target temperature TAO HP, which is the target temperature of the heating heat exchanger 19 in FIG. Step S61).

  If the target blowing temperature TAO is relatively high and higher than 47 ° C., 47 ° C. is set as the heating heat exchanger target temperature TAO HP (step S62). In other words, the heating heat exchanger target temperature TAO HP is set to a low target blowing temperature (TAO HP = 47 ° C. = low target blowing temperature) that restricts the lower one.

  Next, in step S63, it is determined whether or not the water pump 31 of FIG. 1 is operating. If the water pump 31 is in operation, the inlet temperature of the heating heat exchanger 19 in FIG. 1 is greatly affected by the cooling water temperature. Therefore, in step S64, the inlet temperature of the heating heat exchanger 19 = the cooling water temperature. And

  Next, in step S63, if the water pump 31 is stopped, the influence of the temperature of the cooling heat exchanger (evaporator) 18 comes to the inlet of the heating heat exchanger 19 as it is. The inlet temperature of the heat exchanger 19 is set to the evaporator temperature.

  In step S66, the temporary target pressure PDOD for making the post-condenser temperature, which is the air temperature downstream of the heating heat exchanger 19 approximately equal to the heating heat exchanger target temperature TAO HP, is obtained using the map of FIG. To calculate. This temporary target pressure PDOD is calculated when the blower voltage is 4V. FIG. 13 is a map for calculating a temporary target pressure PDOD from the inlet temperature of the heating heat exchanger 19 and the heating heat exchanger target temperature TAO HP.

  In step S67 of FIG. 12, a target pressure (PDO) correction coefficient that is an influence value on the target pressure PDO by the air volume (blower voltage) of the blower 3 of FIG. 1 is calculated. If the air volume is large, even if it is desired to obtain the same temperature after the indoor condenser, the temperature of the heat exchanger 19 for heating needs to be increased, so the target pressure (PDO) correction coefficient corresponding to the blower voltage is calculated. is there.

  In step S68, the temporary target pressure PDO obtained in step S66 (the temporary target temperature PDO is referred to as PDOD) is multiplied by the target pressure (PDO) correction coefficient obtained in step S67 to obtain the current target. Calculate the pressure PDO. FIG. 14 is a map for obtaining the compressor rotation speed change amount ΔfH for heating by the heat pump cycle from the deviation Pn and the deviation change rate PDOT.

  In step S69, using the map of FIG. 14 and the target pressure PDO calculated in step S68, the compressor rotation speed change amount ΔfH for the HOT cycle other than the COOL cycle (heating by the heat pump cycle) is calculated. As described above, the refrigerant pressure sensor 50PRE in FIG. 1 is attached to the refrigerant pipe 55 that connects the compressor 14 and the heat exchanger 19 for heating.

  A pressure deviation Pn between the target pressure PDO obtained in step S68 of FIG. 12 and the high pressure PRE detected by the refrigerant pressure sensor 50PRE is calculated based on the following Equation 5. In the following, n of Pn is a natural number, Pn is the current deviation, and P (n-1) is the previous deviation.

(Formula 5) Pn = PDO-PRE
Further, the deviation change rate PDOT is calculated based on the following Equation 6.

(Formula 6) PDOT = Pn−P (n−1)
Next, by using the deviation Pn and the deviation change rate PDOT, the rotation that increases or decreases with respect to the compressor rotation speed one second ago from the map of FIG. 14 stored in the ROM in the air conditioner control device 5 of FIG. The number change amount ΔfH is obtained.

  Next, FIG. 15 is a map showing the relationship among the deviation Pn, the deviation change rate PDOT, and the compressor rotation speed change amount ΔfC for the COOL cycle.

  In step S70 of FIG. 12, the compressor rotation speed change amount ΔfC during the COOL cycle is calculated using the map of FIG. 15 and the target pressure PDO calculated in step S68.

  Next, in step S71, it is determined whether or not the cycle selected in the cycle selection step of FIG. 8 is a COOL cycle. If it is not the COOL cycle, in step S72, in the HOT cycle, the DRY ALL cycle, and the DRY EVA cycle, under the target rotational speed obtained as “current compressor rotational speed = previous compressor rotational speed + ΔfH”, The compressor 14 is controlled.

In step S71, if the cycle selected in the cycle selection step of FIG. 8 is a COOL cycle, the target rotational speed obtained as “current compressor rotational speed = previous compressor rotational speed + ΔfC” in step S73. , The compressor 14 is controlled.
(Valve ON / OFF decision)
Next, in step S12 of FIG. 7, the ON / OFF operation of the solenoid valve in the cycle is determined so that the control can be executed in a predetermined cycle. This control generates an output signal for turning on / off the operation of each solenoid valve in accordance with the change in the cycle of FIG.
(Control signal output)
Next, in step S13 in FIG. 7, control signals are output to an engine ECU (not shown), various actuators, electromagnetic valves, and servo motors so that the control states calculated or determined in the above steps are obtained. To do. And after waiting for progress of predetermined time in step S14 of FIG. 7, it returns to step S3.

  In the first embodiment, first, during the operation in the HOT cycle in which heating is performed in the heat pump cycle, the opening degree of the air mix door 38 is set to the position of MAX HOT which is a specific position on the heating side. The position may not be a complete MAX HOT position but a specific position in the vicinity thereof.

  Specifically, as described above, when it is determined in steps S50 and S54 in FIG. 11 that heating by the heat pump cycle is being performed, the control to fix the air mix door 38 in FIG. 2 to MAX HOT (MAX HOT) ( (Referred to as fixed control).

  As a result, the temperature of the heating heat exchanger 19 is approximately equal to the blowing temperature, and the minimum necessary temperature of the heating heat exchanger 19 is sufficient for the desired blowing temperature, so that power saving control is possible. . In this power saving control, the air outlet temperature is not adjusted by adjusting the opening degree of the air mix door 38, but the opening degree is fixed, and the air outlet temperature is adjusted by adjusting the temperature of the heat exchanger 19 for heating.

  Second, the target temperature of the heating heat exchanger 19 (heating heat exchanger target temperature TAO HP) in the HOT cycle in which heating is performed by the heat pump is set lower than the target blowing temperature TAO.

  That is, as described above, in FIG. 12, if the target outlet temperature TAO is relatively high and is higher than 47 ° C., 47 ° C. is set as the heating heat exchanger target temperature TAO HP. The value of TAO = 47 ° C. is a value that most people can obtain a sufficient feeling of heating and is not excessively high.

  Specifically, when the target blowing temperature TAO is not higher than the predetermined limit value 47 ° C. (TAO> 47 ° C.), the heating heat exchanger target temperature TAO HP during heating operation by the heat pump cycle is set as the target blowing temperature. The compressor 14 is controlled so as to become TAO.

  At the same time, when the target blowing temperature TAO is higher than the predetermined value 47 ° C. (TAO> 47 ° C.), the heating heat exchanger target temperature TAO HP is set to the limit value 47 lower than the target blowing temperature TAO at this time. The compressor 14 is controlled by setting the temperature so as to be 0 ° C. (TAO HP = 47 ° C.).

  Compared to hot water heating that basically uses engine waste heat, heating by heat pump cycle consumes a large amount of power for air conditioning. Therefore, the target blowout temperature TAO is higher than necessary due to user error. When it is high (TAO> 47 ° C.), the compressor 14 is controlled by setting the heating heat exchanger target temperature TAO HP to be lower than the target outlet temperature TAO (TAO HP = 47 ° C.). Thus, power saving operation can be performed.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. In the following embodiments, the same components as those in the first embodiment described above are denoted by the same reference numerals, description thereof will be omitted, and different configurations and features will be described. FIG. 16 is a flowchart for explaining the steps for determining the compressor speed in the second embodiment of the present invention.

  FIG. 16 is different from FIG. 12 of the first embodiment only in how to determine the inlet temperature of the heating heat exchanger in step S642. In step S642, f (evaporator temperature) is the same as the value obtained in step S53 of FIG. In step S642 of FIG. 16, the inlet temperature of the heat exchanger 19 for heating is calculated as “0.8 × cooling water temperature + 0.2 × f (evaporator temperature)”.

  By calculating the temperature in step S642, the inlet temperature of the heating heat exchanger 19 can be obtained more accurately in consideration of the temperature of the cooling heat exchanger (evaporator) 18. As a result, the temperature of the conditioned air blown into the passenger compartment can be brought closer to the target blow temperature TAO more accurately.

(Other embodiments)
The present invention is not limited to the above-described embodiments, and can be modified or expanded as follows. For example, in each of the embodiments described above, the rotational speed changes ΔfH and ΔfC are simply calculated using a map, but the rotational speed changes ΔfH and ΔfC are not shown in the air conditioner control device 5 of FIG. It can also be obtained by known fuzzy control based on a predetermined membership function and rules stored in the ROM.

  Further, in each of the above embodiments, the refrigerant suction temperature sensor 35 of FIG. 1 may be provided in the outdoor heat exchanger 15, and the detected parameter is converted into a temperature by detecting a parameter such as a low-pressure refrigerant pressure. Then, a predicted value of the refrigerant intake temperature may be calculated, and the calculation result may be used instead of the refrigerant intake temperature. That is, the refrigerant suction temperature T35 may be a measurement value that can monitor the frost formation state of the outdoor heat exchanger 15.

  However, when the refrigerant suction temperature T35 is detected by the refrigerant suction temperature sensor 35, the outdoor heat exchanger 15 can be used in common with a conventional general vehicle. In addition, the system can be configured at a lower price than the pressure detection element that detects the low-pressure refrigerant pressure. In addition, since the measurement error is small, it is desirable to provide the refrigerant suction temperature sensor 35 in the refrigerant pipe.

  And you may put in the step of FIG. 7 the defrosting operation step for the time of frost formation of the outdoor heat exchanger 15 using this refrigerant | coolant suction | inhalation temperature T35.

DESCRIPTION OF SYMBOLS 1 Air-conditioner for electric vehicles 2 Duct which guides ventilation air to room | chamber interior 3 Blower 5 Air-conditioner control apparatus 14 Compressor 14a Electric motor built in the compressor 15 Outdoor heat exchanger 18 Heat exchanger for cooling (evaporator)
19 Heat exchanger for heating 18 and 19 Indoor heat exchanger 30 Engine 31 Water pump 32 Heat exchanger for hot water (heater core)
35 Refrigerant suction temperature sensor 38 Air mix door (air mix means)
50PRE Refrigerant pressure sensor PRE High pressure (measured value)
51 Air-conditioner operation panel Tset Temperature set by the temperature setting switch TAO Target blowout temperature TAO HP Heating heat exchanger target temperature TE Evaporator temperature PDO Target pressure PDOD Temporary target pressure PDOT Deviation change rate Pn Deviation

Claims (6)

A compressor (14) for moving the refrigerant between the indoor heat exchanger (18 and 19) comprising the cooling heat exchanger (18) and the heating heat exchanger (19) and the outdoor heat exchanger (15) is provided. Thus, the COOL cycle operation having a large cooling capacity and the heating operation by the heat pump cycle are performed so that the blow temperature of the blown air by the blower (3) becomes the target blow temperature (TAO) obtained from the set temperature (Tset). A hot water heat exchanger (32) that performs HOT cycle operation and is disposed in the same air path as the heating heat exchanger (19) and uses the waste heat of cooling water, and the hot water heat exchanger (32) and the hot water heat exchanger for controlling a mixed state of the air in the same air path passing through the heating heat exchanger (19) and the cold air having passed through the cooling heat exchanger (18). (32) and Serial and an air mixing means shared with the heating heat exchanger (19) (38), a control method for a vehicle air-conditioning system to perform the heating operation by the hot water heating cycle,
In the heating operation by the COOL cycle and the hot water heating cycle, the cold air that does not pass through the hot water heat exchanger (32) and the hot water as the temperature of the heating heat exchanger (19) is determined to be low. The mixing ratio by the air mixing means (38) with the air passing through the heat exchanger (32) is controlled to the heating side where the mixing ratio of the cold air is small, and the air blower blows into the vehicle interior from the selected outlet Blow,
The refrigerant pressure value is used to calculate the temperature of the heating heat exchanger (19), and the temperature of the heating heat exchanger (19) is calculated with a delay in the change of the refrigerant pressure value,
When switching between the COOL cycle operation and the HOT cycle operation cycle, the temperature of the heating heat exchanger (19) is calculated without delaying the change in the refrigerant pressure value. Control method for vehicle air conditioner.   The opening degree of the air mix means (38) for determining the mixing ratio by the air mix means (38) is determined by a heater (19) comprising the hot water heat exchanger (32) and the heating heat exchanger (19). And 32) the opening degree of the air mix means (38) is calculated so that the opening degree moves to the heating side as the heater temperature becomes lower, and the heater temperature is the heating heat exchanger ( 19) The cold air that does not pass through the hot water heat exchanger (32) as it is determined that the temperature of the heating heat exchanger (19) is low by lowering the temperature of 19). The mixing ratio by the air mixing means (38) with the air passing through the heat exchanger (32) for hot water is controlled to the heating side where the mixing ratio of the cold air is small. Control method for vehicle air conditioner. Furthermore, when the mode of the outlet is selected according to at least the target outlet temperature (TAO), and the mode of the outlet is the face mode and the COOL cycle is selected, the cooling water temperature is reduced or When it is determined that the blowing temperature of the blown air is lower than the target blowing temperature (TAO) due to a decrease in the temperature of the heat exchanger for heating (19), the temperature is higher than the target blowing temperature (TAO). The method for controlling a vehicle air conditioner according to claim 1 or 2 , wherein the blower (3) is configured to reduce the amount of air blown compared to when it is determined that the blown air temperature is not low. In order to make the blowing temperature of the blown air by the blower (3) become the target blowing temperature (TAO), control is performed so that the refrigerant pressure becomes a target pressure (PDO) that is a target value of the refrigerant pressure, In calculating the target pressure (PDO), the target outlet temperature (TAO), the air volume or blower voltage of the blower (3), and the heating heat exchanger inlet temperature that becomes the intake air temperature of the heating heat exchanger (19) When the cooling water is flowing into the hot water heat exchanger (32), the heating heat exchanger inlet temperature is calculated using the cooling water temperature, and the hot water heat exchanger (32 vehicle according to any one of claims 1 to 3 time characterized by calculation using the evaporator temperature is a temperature of the cooling heat exchanger (18)) the cooling water does not flow to the Control method for industrial air conditioners. The air mixing means (38) is formed as a single air mixing means (38) disposed upstream of the hot water heat exchanger (32) and the heating heat exchanger (19). The control method of the vehicle air conditioner as described in any one of Claims 1 thru | or 4 characterized by the above-mentioned. When the cooling water is flowing, the heating heat exchanger inlet temperature is calculated using the cooling water temperature and an evaporator temperature correction value that is a function value of the evaporator temperature (TE). The method for controlling a vehicle air conditioner according to claim 4 .

Images