Vehicle air conditioning system

Abstract

To optimize power consumption in a heating system.SOLUTION: In an outside air mode, outside air from an outside air intake port 10b is introduced into a ventilation duct 10, in an inside air mode, inside air from an inside air intake port 10a is introduced into the ventilation duct 10, and in an inside / outside air mixed mode, both outside air from the outside air intake port 10b and inside air from the inside air intake port 10a are introduced into the ventilation duct. When a cabin is heated in the inside air mode or the inside / outside air mixed mode, a control section 70 makes a total amount of air blown out from an outlet port pass through a heater core 40, and sets a heat medium temperature in the heating system in accordance with a temperature of air passing through an evaporator 20.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a vehicle air conditioning system using a heater. [Background technology]

[0002] Conventionally, gasoline engine vehicles and hybrid vehicles use waste heat from the engine for heating. On the other hand, electric vehicles and hybrid vehicles cannot use waste heat from the engine when they are running as electric vehicles. Therefore, a heat pump used for air conditioning is used to heat the vehicle by using heat absorbed from the outside air or heat generated by a heater as a heat source. Patent Document 1 describes heating using a heat pump. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-143533 A Summary of the Invention [Problem to be solved by the invention]

[0004] Here, even when a heater or the like is used, the heating temperature of the heater is set relatively high, as in the case of using waste heat from the engine, and the outlet temperature is controlled by controlling the amount of heat exchange therein.

[0005] However, heating sources such as heaters use battery power, and inefficient use of it can result in higher cost per mile and reduced range.

[0006] The present invention provides a vehicle air conditioner that can effectively utilize a heater. [Means for solving the problem]

[0007] The vehicle air conditioner according to the present disclosure is an air conditioner for a vehicle, the air conditioner including a heat pump system that circulates a heat medium to an evaporator and a condenser, a heater, a heating system that circulates a heat medium to a heater core, an air duct in which the evaporator and the heater core are disposed and which takes in air from an intake port formed on one side and blows out air from an outlet port formed on the other side, and a control unit that controls a heat medium temperature in the heating system, the intake port including an outside air intake port that takes in air outside the vehicle cabin and an inside air intake port that takes in inside air inside the vehicle cabin, in an outside air mode, outside air from the outside air intake port is introduced into the air duct, in an inside air mode, inside air from the inside air intake port is introduced into the air duct, and in an inside / outside air mixed mode, both the outside air from the outside air intake port and the inside air from the inside air intake port are introduced into the air duct, and the control unit controls an inside air temperature, which is the temperature inside the vehicle cabin, , Outside temperature and based on the set temperature which is the target for the internal air temperature The higher the set temperature, the higher the temperature will be. The higher the indoor and outdoor temperatures, the lower the temperature will be. A target outlet temperature of the air blown out from the outlet is determined, and the target outlet temperature is set to the determined target outlet temperature. With the specified top-up a target heat medium temperature in the heating system is set, and when the vehicle interior is heated in an inside air mode or an inside / outside air mixed mode, all of the air blown out from the air outlet is caused to pass through the heater core; From the set target heat transfer medium temperature The inside air temperature and the outside air temperature Subtract the temperature difference and The larger the difference is, the lower the set target heat medium temperature is corrected. Effect of the Invention

[0008] According to the vehicle air conditioning system of the present disclosure, the heating system heat medium temperature is set according to the inside air temperature, so that the power consumption of the heater in the heating system can be appropriate and the vehicle's cruising distance can be extended. [Brief description of the drawings]

[0009] [Figure 1] 1 is a diagram illustrating a schematic configuration of an example of a vehicle air conditioning device according to an embodiment; [Diagram 2]FIG. 11 is a diagram showing the relationship between a target outlet temperature TAO and a target water temperature TWO. [Diagram 3] 5 is a flowchart showing a process for setting a corrected target water temperature TWO2 in the present embodiment. [Figure 4] FIG. 11 is a diagram showing the circulation state of outside air and inside air in a two-layer circulation mode. [Diagram 5] FIG. 1 is a conceptual diagram of a two-layer mode in a vehicle. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the following embodiments do not limit the present disclosure, and configurations obtained by selectively combining multiple examples are also included in the present disclosure.

[0011] 1 is a diagram showing a schematic configuration of an example of a vehicle air conditioner according to an embodiment. An air duct 10 has an inside air intake 10a and an outside air intake 10b. The inside air intake 10a takes in air from inside the vehicle cabin, and takes in the inside air from openings provided at the front and rear of the vehicle cabin. The outside air intake 10b takes in outside air (atmosphere) from outside the vehicle, and usually takes in the atmosphere from an opening provided at the front of the vehicle.

[0012] A blower 12 is disposed inside the inside air intake 10a and the outside air intake 10b of the ventilation duct 10. The blower 12 has a fan 12b driven by a motor 12a, and air (inside air and outside air) is taken in from the inside air intake 10a and the outside air intake 10b by the rotation of the fan 12b. A damper 14 is disposed inside the inside air intake 10a and the outside air intake 10b. The damper 14 adjusts the opening degree of the inside air intake 10a and the outside air intake 10b, and can be adjusted from 100% inside air (0% outside air) to 0% inside air (100% outside air) depending on the position of the damper 14. The blower 12 and the damper 14 may be provided separately for the inside air and the outside air so that they can be controlled independently.

[0013] An evaporator 20 is disposed downstream of the blower 12 in the ventilation duct 10. A compressor 22, a condenser 24, and a pressure reducing valve 26 are connected to the evaporator 20 to form a circulation path. A heat pump system is configured by circulating a heat medium through the circulation path. The heat pump system performs indoor cooling by vaporizing the heat medium in the evaporator 20 to remove heat from the air in the ventilation duct 10 and discharging the heat to the outside in the condenser 24. However, as described in Patent Document 1, the heat dissipation of the heat pump system can also be used for heating by providing a second condenser or other means. During heating, the compressor 22 can be stopped or the pressure reducing valve 26 can be opened to set the evaporator 20 to room temperature (indoor air temperature). The temperature of the air after passing through the evaporator 20 is measured by a sensor 28. The air temperature measured by the sensor 28 can be regarded as the indoor temperature (indoor air temperature).

[0014] An air mix damper 30 is disposed downstream of the evaporator 20. The air mix damper 30 is movable from an upper closed position to a lower closed position. A heater core 40 is disposed in the upper passage downstream of the air mix damper 30. When the air mix damper 30 is in the lower closed position, 100% of the air flowing in the ventilation duct 10 bypasses the heater core 40, and when the air mix damper 30 is in the upper closed position, 100% of the air flowing in the ventilation duct 10 passes through the heater core 40.

[0015] A pump (WP) 42 and a heater 44 are connected to the heater core 40 to form a circulation path, thereby forming a heating system. In this example, water is circulated through this circulation path as a heat medium. The heater 44 is, for example, an electric heater, and heats the circulating water. The temperature of the circulating water is measured by a water temperature sensor 46. Also, instead of or in parallel with the heater 44, a condenser of a heat pump system may be provided, and the circulating water may be heated by this heat pump system.

[0016] Three outlets are provided downstream of the heater core 40: a foot-side outlet 50, a passenger-side outlet 52, and a defrost-side outlet 54. The foot-side outlet 50 blows air from inside the ventilation duct 10 toward the feet of the occupants in the driver's seat and the passenger's seat, the passenger-side outlet 52 blows air toward the upper bodies of the occupants in the driver's seat and the passenger's seat, and the defrost-side outlet 54 blows air from the bottom toward the top of the inside of the windshield.

[0017] A foot side damper 56 is provided at the foot side outlet 50, a passenger side damper 58 is provided at the passenger side outlet 52, and a defrost side damper 60 is provided at the defrost side outlet 54, making it possible to control the air blown out from the ventilation duct 10. Here, in this example, the foot side damper 56, the passenger side damper 58, and the defrost side damper 60 are adapted to have their opening and closing operations controlled by a drive unit 62.

[0018] The control unit 70 controls the opening and closing of the damper 14, the air mix damper 30, and the three dampers on the blowing side, the heating of the heater 44, etc. The control unit 70 is supplied with temperatures from an inside air sensor 72 provided near the inside air intake 10a, an outside air sensor 74 provided near the outside air intake 10b, and a water temperature sensor 46 provided in the water circulation path to the heater core 40. In addition, a solar radiation sensor 76 that measures the intensity of outside light entering the vehicle cabin is provided near the windshield glass, and this detection value is also supplied to the control unit 70. In addition, a control panel 80 is provided that accepts inputs from the occupant regarding the temperature setting in the vehicle cabin, switching between outside air mode, inside air mode, and inside / outside air mixed mode, and selection of the air outlet, etc., and operation signals from this panel are supplied to the control unit 70.

[0019] Regarding the intake of inside and outside air, when the outside air intake 10b is fully closed and the inside air intake 10a is fully opened by the damper 14, it is the inside air mode (damper 14: position indicated by dashed line), when the outside air intake 10b is fully opened and the inside air intake 10a is fully closed by the damper 14, it is the outside air mode (damper 14: position indicated by sand), and the intermediate mode is the inside and outside air mixed mode.

[0020] "Temperature control" The control unit 70 controls the damper 14, air mix damper 30, heater 44, etc. based on the set temperature (set value) set on the control panel 80, the setting of the outside air / inside air mode, the selection of the air outlet, etc., as well as the detection values ​​of the various sensors mentioned above.

[0021] <Target outlet temperature TAO> The control unit 70 calculates the target outlet temperature TAO based on the room temperature (inside air temperature) TR, the set temperature (set value) TSET of the inside air temperature, the detection values ​​of the various sensors described above, and the like. TAO=E×(TSET+ΔT)-F×TR-G×TAM-H×TS+C

[0022] Here, TSET is the set temperature, TR is the room temperature (corresponding to the indoor air temperature), TAM is the outdoor air temperature, TS is the amount of solar radiation, ΔT and C are correction constants, and E, F, and H are coefficients.

[0023] Although various corrections are made, such as multiplying by a coefficient, the target outlet temperature is set by subtracting the outside air temperature TAM and the indoor temperature TR from the set temperature TSET. In other words, the higher the set temperature TSET, the higher the temperature is, and the higher the outside air temperature TAM and the indoor temperature TR, the lower the temperature is.

[0024] Which outlet to blow air from is determined based on the settings on the control panel 80. Also, the air volume will be the air volume if set on the control panel 80, but if the air volume is set automatically, it may be determined according to the required heat amount for room heating, and for example, it may be set to a larger value as the TAO is higher.

[0025] The target outlet temperature TAO may be determined by using a lookup table or the like, rather than by using a mathematical formula.

[0026] <Maximum heating MAXHOT> When the amount of heat that can be supplied for the required heating is insufficient, the control unit 70 determines that the state is MAXHOT, and sets the air mix damper 30 to a state in which all the heat passes through the heater core 40 .

[0027] <Two target water temperature settings> The target water temperature TWO of the heat medium (water) circulating through the heater core 40 is determined in correspondence with the target outlet temperature TAO. That is, taking into consideration the efficiency of heat exchange in the heater core 40 and the heat loss in the duct leading to the outlet, a predetermined value is added to the target outlet temperature TAO to set it slightly higher than TAO. For example, as shown in Fig. 2, until the target outlet temperature TAO = 30°C, the target water temperature TWO is constant at 50°C, thereafter there is a one-to-one correspondence up to 70°C, and thereafter it is constant at 90°C.

[0028] In this way, the target water temperature TWO is determined by adding a certain amount (20°C in the above case) depending on the target outlet temperature. Here, the air mix damper 30 is provided, and air that does not pass through the heater core 40 can be mixed, and engine waste heat can often be utilized, so the target water temperature TWO is set relatively high. In this example, the outside air temperature is set to 5°C, and the indoor temperature is set to the same value to calculate the heat loss. The actual measured temperature can be used as the outside air temperature, but it may also be fixed at a general temperature (for example, 5°C).

[0029] <Corrected target water temperature TWO2 setting> As described above, the target water temperature TWO is basically set to have a certain relationship with the target outlet temperature TAO. The air flowing into the heater core 40 is the air that has passed through the evaporator 20 and has a temperature equivalent to room temperature. As described above, it is assumed that the amount of air passing through the heater core 40 can be controlled by the air mix damper 30.

[0030] Therefore, in this embodiment, when the entire amount of air can pass through the heater core 40 under conditions such as the required air volume, the control unit 70 sets the state to the MAXHOT state.

[0031] As a result, the air mix damper 30 completely closes the upper passage, and the entire amount of air is introduced into the heater core 40.

[0032] Then, the target water temperature TWO is corrected according to the actual indoor temperature, that is, the air temperature after passing through the evaporator 20 measured by the sensor 28 (which can be regarded as the same as the indoor air temperature).

[0033] For example, when TAO=50° C., TWO=70° C. Then, the corrected target water temperature TWO2=60° C. is calculated by subtracting the difference Te: inside air temperature (15° C.)-TAM: outside air temperature (5° C.) from the obtained TWO=70° C. TWO2=TWO(70)-(Te(15)-TAM(5))=60

[0034] As a result, the target water temperature TWO=70° C. is reduced in accordance with the inside air temperature to obtain a corrected target water temperature TWO2=60° C.

[0035] Here, TWO is a temperature assuming that the air that does not pass through the heater core 40 is appropriately introduced by the air mix damper 30. TWO2 is a temperature when the entire amount of air is made to pass through the heater core 40, and there is no change in the blowing temperature TAO = 50°C.

[0036] Therefore, according to this embodiment, the water temperature (heat medium temperature) of the heat medium (water) circulating through the heater core 40 can be lowered, and the electric power of the heater 44 can be reduced.

[0037] In this way, by using the corrected target water temperature TWO2, the power required for heating as described above when the outside air temperature is 5°C can be reduced by about 40%, which increases the cruising distance per charge by about 10%.

[0038] In this embodiment, the intake of outside air and inside air can be adjusted by operating the damper 14. In the case of mixing outside air and inside air, if the inside air ratio is α, then TWO2 (corrected target water temperature) = TWO (target water temperature) - α (Te (inside air temperature) - TAM (outside air temperature)) The outside air temperature TAM may be a constant value or an actual measured value.

[0039] <Processing flow> FIG. 3 is a flowchart showing a process for setting the corrected target water temperature TWO2 in this embodiment.

[0040] First, it is determined whether the air conditioning is on (S11). If the determination in S11 is YES, it is determined whether it is MAXHOT (S12), and if the determination in S12 is YES, it is determined whether it is the outside air mode (S13). If the determination in S13 is YES, the corrected target water temperature TWO2 is set to the temperature obtained by subtracting a correction value according to the inside air temperature (inside air temperature Te-outside air temperature TAM) (S14). If the determinations in S11 to S13 are NO, TWO2=TWO (S15).

[0041] As a result, when the entire amount of air in the duct passes through the heater core 40, the target water temperature TWO is corrected to the corrected target water temperature TWO2, making it possible to maintain the outlet temperature while setting it to a relatively low temperature.

[0042] <Air mix damper> The operation of the air mix damper 30 will be described. The air mix damper 30 controls the amount of air passing through the heater core 40. As described above, the target water temperature TWO is set relatively high. Therefore, in order to obtain the target outlet temperature TAO, the air mix damper 30 controls the proportion of air passing through the heater core 40, thereby making it possible to obtain the desired target outlet temperature TAO.

[0043] For example, the ratio AM of air passing through the heater core 40 is calculated from the target outlet temperature TAO and the inside air temperature Te as follows: AM = (TAO-Te) / (TWO-Te) It can be determined by:

[0044] <Two-tier distribution mode> Fig. 4 is a diagram showing the flow of outside air and inside air in the two-layer flow mode. In this example, the inside of the duct is separated into an upper layer and a lower layer by a partition wall 90. Here, the blower 12 includes a fan 12b-1 for inside air and a fan 12b-2 for outside air, and both can be driven independently. It also has an air outlet 92 toward the rear seat side.

[0045] In the figure, the inside air and outside air are shown to flow completely separately, with the inside air and outside air intakes, the outlet dampers, and the air mix damper 30 omitted. In the configuration of Fig. 4, a damper for mixing the upper and lower layers of air can be provided, which makes it possible to realize a mixed mode of inside air and outside air, and also makes it possible to heat the taken-in outside air with the heater core 40.

[0046] In the two-layer circulation mode, as shown in the figure, if the outside air is blown into the room without passing through the heater core 40, or if some of the outside air is introduced into the lower layer but all of the air in the lower layer is made to pass through the heater core 40, heating can be performed using the corrected target water temperature TWO2 as described above.

[0047] 5 is a conceptual diagram of the two-layer mode in the vehicle 100. Outside air circulates through the upper part of the vehicle interior, and inside air circulates in the lower part of the vehicle interior. [Explanation of symbols]

[0048] 10 ventilation duct, 10a inside air intake, 10b outside air intake, 12 blower, 14 damper, 20 evaporator, 22 compressor, 24 condenser, 26 pressure reducing valve, 28 sensor, 30 air mix damper, 40 heater core, 44 heater, 46 water temperature sensor, 50 foot side outlet, 52 passenger side outlet, 54 defrost side outlet, 56 foot side damper, 58 passenger side damper, 60 defrost side damper, 62 drive unit, 70 control unit, 72 inside air sensor, 74 outside air sensor, 76 solar radiation sensor, 80 control panel, 90 bulkhead, 92 outlet, 100 vehicle.

Claims

[Claim 1] An air conditioning device for a vehicle, A heat pump system that circulates a heat medium to an evaporator and a condenser; a heater; a heating system that circulates a heat medium through the heater core; an air duct in which the evaporator and the heater core are disposed, the air duct taking in air from an intake port formed on one side and blowing out air from an outlet port formed on the other side; A control unit for controlling a heat medium temperature in the heating system; having The intakes include an outside air intake for taking in air outside the vehicle cabin and an inside air intake for taking in air inside the vehicle cabin. In the outside air mode, outside air from the outside air intake is introduced into the ventilation duct, in the inside air mode, inside air from the inside air intake is introduced into the ventilation duct, and in the inside / outside air mixed mode, both the outside air from the outside air intake and the inside air from the inside air intake are introduced into the ventilation duct, the control unit determines a target blowing temperature of the air blown out from the outlet based on an inside air temperature, which is a temperature inside the vehicle interior, an outside air temperature, and a set temperature which is a target for the inside air temperature, so that the higher the set temperature is, the lower the higher the inside air temperature and the outside air temperature are, sets a target heat medium temperature in the heating system by adding a predetermined value to the determined target blowing temperature, and when the vehicle interior is heated in an inside air mode or an inside / outside air mixed mode, passes all of the air blown out from the outlet through the heater core, subtracts a temperature difference between the inside air temperature and the outside air temperature from the set target heat medium temperature, and corrects the temperature difference so that the set target heat medium temperature is lowered as the temperature difference is larger. Vehicle air conditioning system.

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