WO2023090083A1

WO2023090083A1 - Vehicle air-conditioning device

Info

Publication number: WO2023090083A1
Application number: PCT/JP2022/039797
Authority: WO
Inventors: 雲生黄; 佳之岡本; めぐみ重田; 耕平山下; 貴司戸山; 竜宮腰
Original assignee: サンデン株式会社
Priority date: 2021-11-19
Filing date: 2022-10-25
Publication date: 2023-05-25
Also published as: JP2023075844A

Abstract

[Problem] To enable heating in a cryogenic environment to continue for a predetermined period of time without the use of supplemental heating by, e.g., a PTC heater, by continuing hot gas heating in a vehicle air-conditioning device using a heat pump. [Solution] This vehicle air-conditioning device comprises: a refrigerant circuit that is equipped with at least a compressor and circulates hot refrigerant from the compressor; an air heater that heats the air in the passenger compartment by releasing heat from the refrigerant; and a controller that controls the amount of heat released from the refrigerant. The controller has a hot gas heating continuation mode in which the amount of heat released from the refrigerant is equal to or less than the amount of heat input from the compressor.

Description

vehicle air conditioner

The present invention relates to a vehicle air conditioner.

Air conditioners that use a heat pump as a heat source are known as air conditioners for electric vehicles (EVs) that do not have a combustion heat source such as an engine or for vehicles that have a small amount of heat from the combustion heat source.

An air conditioner that uses a heat pump uses an external heat exchanger to function as a heat absorber during heating operation, and obtains the heating heat source from the outside air. Therefore, when the outside air temperature becomes extremely low, it becomes difficult to absorb heat from the outside air, resulting in a large decrease in the heating capacity. On the other hand, if an electric heater such as a PTC heater is used to secure the heat source, the consumption of the battery increases, and in the case of an electric vehicle, there is concern that it will adversely affect the travelable distance. The manufacturing cost of the device will increase.

　Hot gas heating using a heat pump compressor is a heating method that does not absorb heat from outside air. In this hot gas heating system, the high-temperature refrigerant discharged from the compressor is sent to the radiator, which is the heat exchanger inside the passenger compartment, and the refrigerant discharged from the radiator is depressurized without going through an external heat exchanger and returned to the compressor. (See Patent Document 1 below).

JP 2014-196017 A

In vehicle air conditioning systems that use heat pumps, when the aforementioned hot gas heating is used to perform heating operation in extremely low temperature environments, the compressor is normally operated at a set rotation speed close to its capacity limit. Become. At this time, the amount of heat released by the heat exchanger in the passenger compartment increases according to the heating demand, and when the amount of heat released increases relative to the energy consumption (heat input) of the compressor, the compressor continues to operate at the upper limit rotation speed. Hot gas heating cannot be continued even if the

Focusing on such problems, the present invention aims to continuously use hot gas heating. That is, in a vehicle air conditioner using a heat pump, by continuing hot gas heating, heating can be continued for a predetermined time in an extremely low temperature environment without using auxiliary heating such as a PTC heater. This is the subject of the present invention.

In order to solve such problems, the present invention has the following configurations.
A refrigerant circuit that includes at least a compressor and circulates a high-temperature refrigerant discharged from the compressor, an air heating device that heats air in a vehicle compartment by heat radiation of the refrigerant, and a control device that controls the amount of heat released by the refrigerant. wherein the control device has a hot gas heating continuation mode in which the amount of heat released by the refrigerant is equal to or less than the amount of heat input from the compressor.

According to the present invention having such features, it is possible to continue hot gas heating in an extremely low temperature environment for a predetermined period of time, improving the practicality of a vehicle air conditioner using a heat pump. Moreover, since heating can be performed in a cryogenic environment without using auxiliary heating such as a PTC heater, the manufacturing cost of the air conditioner can be suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram showing the configuration of a vehicle air conditioner and the flow of refrigerant according to an embodiment of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram showing the configuration of a vehicle air conditioner and the flow of refrigerant according to an embodiment of the present invention; 1 is a block diagram of a control device in a vehicle air conditioner according to an embodiment of the present invention; FIG. Explanatory drawing which showed the basic control flow of hot gas heating continuation mode. Timing chart showing an example of control in the hot gas heating continuation mode ((a) is an example of controlling the blower output voltage according to the heat radiation amount of the heat radiating part of the indoor air conditioning unit, (b) is the heat radiation amount of the refrigerant-heat medium heat exchanger. (Example of controlling the heat medium flow rate by FIG. 4 is an explanatory diagram showing another control flow example for executing the hot gas heating continuation mode; FIG. 6 is a timing chart diagram of an example of control ((a) is control based on time-series changes in the heat radiation amount Q _icnd of the heat radiating unit, and (b) is control based on time-series changes in the compressor discharge pressure P _ci ). FIG. 2 is a flowchart showing a specific control example of the vehicle air conditioner according to the embodiment of the present invention; 1 is an explanatory diagram showing a configuration example of a control device in an electric vehicle (EV) equipped with a vehicle air conditioner; FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same reference numerals in different figures denote portions having the same function, and duplication of description in each figure will be omitted as appropriate.

FIG. 1 shows a configuration example of a vehicle air conditioner according to an embodiment of the present invention. The vehicle air conditioner 1 includes an indoor air conditioning unit 10 that functions as an air heating device that heats the air in the vehicle interior, and a refrigerant circuit 20 .

The indoor air conditioning unit 10 of the vehicle air conditioner 1 shown in FIG. 1 includes

indoor heat exchangers

11 and 12 . In addition, the indoor air conditioning unit 10 is provided with a blower 13 for blowing the air in the vehicle interior to the

indoor heat exchangers

11 and 12 in the air blowing layer 10A on the upstream side of the indoor heat exchanger 11. The wind receiving layer 10B on the side is provided with an air flow path (not shown) leading to the vehicle interior. Further, the indoor air conditioning unit 10 is provided with an air damper 14 that is driven to open and close by an air damper driving section 14A. The blowing amount of the air passing through the

indoor heat exchangers

11 and 12 can be adjusted by adjusting the blowing amount of the air blower 13 and the opening/closing of the air damper 14 .

The refrigerant circuit 20 of the vehicle air conditioner 1 shown in FIG. 1 constitutes a heat pump and can perform a heating operation or a cooling operation, and includes refrigerant flow switching means capable of switching to the heat pump cycle. ing. Hot gas heating can be performed by selecting the refrigerant flow path indicated by the thick line in the drawing.

The refrigerant circuit 20 includes a compressor 2 that compresses and discharges vaporized refrigerant, a pressure reducing valve 22 (22A, 22B, 22C, 22D) that reduces the pressure of the refrigerant compressed by the compressor 2 to a predetermined pressure, and a refrigerant. The compressor 2 includes a channel switching valve 23 (23A, 23B, 23C, 23D) for switching channels, and an accumulator 21 provided upstream of the compressor 2.

In addition, the refrigerant flow path of the refrigerant circuit 20 is connected to the

indoor heat exchangers

11 and 12 described above, an external heat exchanger 24 for the refrigerant to exchange heat with the outside air, and the refrigerant flows through the heat medium circuit 30. It is connected to a refrigerant-heat medium heat exchanger 25 or the like for exchanging heat with a heat medium. Further, the refrigerant circuit 20 is provided with a check valve 26 and the like as necessary.

In the illustrated example, by closing the flow

path switching valves

23C and 23D, hot gas heating can be performed by the refrigerant flow path indicated by the thick line. During execution of hot gas heating, the high-temperature refrigerant discharged from the compressor 2 flows through the indoor heat exchanger 12 functioning as a heat radiating section, and the refrigerant discharged from the indoor heat exchanger 12 flows through the flow switching valve 23A and the pressure reducing valve 22A. , the refrigerant-heat medium heat exchanger 25 and the accumulator 21 to the compressor 2 . Also, the refrigerant that has exited the compressor 2 passes through the bypass flow path 3 bypassing the indoor heat exchanger 12 and the like, and returns to the compressor 2 via the accumulator 21 .

In the example shown in FIG. 1, only the indoor heat exchanger 12 is used as the heat radiation part in the indoor air conditioning unit 10, and the refrigerant flow path is through the refrigerant-heat medium heat exchanger 25. However, in FIG. As shown, by fully closing the pressure reducing valve 22A, both the

indoor heat exchangers

11 and 12 of the indoor air conditioning unit 10 are used as heat dissipation units, and the refrigerant flow path that bypasses the refrigerant-heat medium heat exchanger 25 It is also possible to carry out hot gas heating.

In the example shown in FIG. 1, the refrigerant circuit 20 adjusts the throttle amount of the pressure reducing valve 22A and the pressure reducing valve 22B so that the ratio of the flow rate of the bypass flow path 3 and the flow rate of the other flow paths (flow rate ratio) is It is adjustable. Similarly, in the example shown in FIG. 2, the above-described flow ratio can be adjusted by adjusting the throttling amounts of the

pressure reducing valves

22C and 22B. Here, by adjusting the flow rate ratio so that the flow rate of the bypass flow path 3 increases, the flow rate of the refrigerant returning to the compressor 2 with less heat dissipation increases, and the heat dissipation amount of the refrigerant can be reduced.

The vehicle air conditioner 1 also includes a control device 4 as shown in FIG. The control device 4 is an air conditioning ECU (Electronic Control Unit) for executing various control modes of the vehicle air conditioner 1, and when executing hot gas heating, controls the amount of heat released by the refrigerant to perform hot gas heating. It has a hot gas heating continuation mode that continues the hot gas heating.

The control device 4 acquires detection information from various sensors in order to grasp the operation status of the vehicle air conditioner 1 . In the hot gas heating continuation mode described above, as shown in FIG. is input, the control device 4 controls the flow path switching valve driving units S1 to S4 to open and close the flow path switching valves 23 (23A to 23D) to select the refrigerant flow path, while the compressor 2, The air blower 13, the air damper driver 14A, the heat medium circulation pump 31, and the pressure reducing valve drivers E1 to E4 are controlled to control the heat release amount of the refrigerant.

FIG. 4 shows a basic control flow of the controller 4 in the hot gas heating continuation mode. From the start of control, the amount of heat input (Q _comp ) from the compressor 2 is grasped (step S1), the heat radiation amount (Q _out ) of the refrigerant in the refrigerant circuit 20 is grasped (step S2), and the amount of heat input (Q _comp ) and the amount of heat radiation (Q _out ) are compared (step S3), and if Q _comp ≧Q _out is established (step S3: YES), the hot gas heating can be continued, responding to the heating request (Step S4), the control cycle ends.

Further, when Q _comp ≧Q _out does not hold (step S3: NO), it is determined that the hot gas heating cannot be continued, and a process (step S5) is performed to reduce the amount of heat released by the refrigerant (Q _out ). After that, the control cycle ends. In the hot gas heating continuation mode, by repeating the control cycle of this basic control flow, when Q _comp ≧Q _out does not hold, processing is performed to reduce the heat release amount (Q _out ) of the refrigerant, and Q _comp ≧ Q Hot gas heating can be continued by returning to a state in which _out is established.

Here, the amount of heat input (Q _comp ) from the compressor 2 can be grasped by monitoring the power consumption of the compressor 2 . The heat input (Q _comp ) can be obtained by, for example, multiplying the power consumption of the compressor 2 by a predetermined coefficient.

The heat release amount (Q _out ) of the refrigerant in the refrigerant circuit 20 can be grasped, for example, by grasping the following (1) to (3) individually or collectively.

(1) Amount of heat radiation from the heat radiating sections (indoor heat exchangers 11 and 12) in the indoor air conditioning unit 10, (2) Amount of heat radiation from the refrigerant circuit 20 to the environment, (3) Heat medium circuit 30 in the refrigerant-heat medium heat exchanger 25 Amount of heat dissipated to

In (1) to (3) above, the most important heat release amount when continuing hot gas heating is the heat release amount of the heat radiating section in the indoor air conditioning unit 10 in (1) above. When grasping the heat dissipation amount (Q _out ) of the refrigerant described above, first grasp the heat dissipation amount of the above (1), and then add the influence of the heat dissipation amount of the above (2) as a disturbance as necessary. Furthermore, it is preferable to consider the amount of heat release in (3) above when the heat medium circuit 30 is in operation.

First, a case will be described in which the heat release amount (Q _out ) of the refrigerant corresponds to the heat release amount (Q _icnd ) of the heat release portion (the indoor heat exchanger 12 in FIG. 1) of the indoor air conditioning unit 10 .

The heat radiation amount (Q _icnd ) of the heat radiation portion in the indoor air conditioning unit 10 is obtained by the following formula.
Q _icnd = (Thp−Te)×Ga×K
Here, Thp: blown air temperature, Te: intake air temperature, Ga: amount of air blown through the radiator, K: calculation constant.

The blown air temperature (Thp) here is a value detected by the above-mentioned blast temperature sensor Ta2, and the intake air temperature (Te) is a value detected by the above-mentioned blast temperature sensor Ta1. Also, the amount of air blown through the heat radiating portion Ga is a calculated value obtained from the output of the blower 13 and the opening degree of the air damper 14 . The calculation constant (K) is a set value preset in the system.

Then, in the above step S3, it is determined whether Q _comp ≧Q _icnd holds, and when Q _comp ≧Q _icnd does not hold, the process (step S4) of reducing the heat release amount (Q _out ) of the refrigerant is as follows: It is executed by the following (a) to (c).

(a) reduction in the amount of air blown through the heat radiating section Ga, (b) increase in the flow rate ratio of the refrigerant flowing through the bypass passage 3, and (c) reduction in the flow rate of the heat medium flowing through the refrigerant-heat medium heat exchanger 25.

Here, the above (a) can be performed by appropriately combining the output reduction of the blower 13 and the opening degree increase of the air damper 14, or by controlling one of them. By reducing the amount Ga of air blown through the heat radiating section, the heat radiating amount of the heat radiating section in the indoor air conditioning unit 10 is reduced, and the heat radiating amount (Q _out ) of the refrigerant can be reduced.

The above (b) can be performed by adjusting the throttle amounts of the

pressure reducing valves

22A and 22B in the flow path state of FIG. 1 (throttle amount adjustment of the

pressure reducing valves

22C and 22B in the flow path state of FIG. 2). By increasing the flow rate ratio of the refrigerant flowing through the bypass flow path 3, the amount of refrigerant flowing through the heat radiating portion in the indoor air conditioning unit 10 is reduced, and the heat radiation amount (Q _out ) of the refrigerant can be reduced.

The above (c) can be performed by reducing the rotational speed of the heat medium circulation pump 31 when the heat medium circuit 30 is in operation. By reducing the flow rate of the heat medium flowing through the refrigerant-heat medium heat exchanger 25 during operation of the heat medium circuit 30, the heat release amount of the refrigerant-heat medium heat exchanger 25 in the heat medium circuit 30 is reduced, and the heat release amount of the refrigerant is reduced. (Q _out ) can be reduced.

FIG. 5 shows an example of control. In the example shown in FIG. 5(a), the amount of heat dissipation (Q _out ) of the refrigerant is grasped by the amount of heat dissipation (Q _icnd ) of the heat radiating section in the indoor air conditioning unit 10, Q _comp and Q _icnd are compared, and Q _comp ≧ Control is performed to reduce the output voltage of the blower 13 when Q _icnd is no longer established. In the illustrated example, at timing T1 when Q _icnd −Q _comp ≧α, the output voltage of the blower 13 is lowered from V1 to V2 (V1>V2), thereby reducing the amount of heat dissipation (Q _icnd ). , Q _comp ≧Q _icnd .

In the illustrated example, after Q _comp ≧Q _icnd is established, the output voltage of the blower 13 is increased from V2 to V3 (V2<V3) at a predetermined timing T2 so as to meet the desired heating request. there is Here, by controlling the output voltage of the blower 13, the amount of air blown through the heat radiating section Ga is controlled. It is also possible to control the part-passing air flow rate Ga.

In the example shown in FIG. 5B, the heat release amount (Q _out ) of the refrigerant is grasped by the heat release amount (Q _chil ) in the heat medium circuit 30, Q _comp is compared with Q _chil , and Q _comp ≧Q _chil is satisfied. Control is performed to decrease the heat medium flow rate by decreasing the rotation speed of the heat medium circulation pump 31 when this does not hold true. In the illustrated example, at timing T1 when Q _chil −Q _comp ≧α, the heat medium flow rate is lowered from L1 to L2 (L1>L2), thereby reducing the amount of heat release (Q _chil ) and increasing Q It holds _comp ≧Q _chil . In the illustrated example, after Q _comp ≧Q _chil is established, the heat medium flow rate is increased from L2 to L3 (L2<L3) at a predetermined timing T2 so as to meet the temperature control request of the heat medium circuit 30. I have to.

FIG. 6 shows another control flow example for executing the hot gas heating continuation mode. Here, on the premise that the rotation speed of the compressor 2 is constant (upper limit), based on the time series change of the heat radiation amount (Q _icnd ) of the heat radiating unit or the discharge pressure (P _ci ) of the compressor 2 , estimate the relationship between heat input (Q _comp ) and heat release (Q _out ).

In the example of FIG. 6, the current value of the heat radiation amount (Q _icnd ) of the heat radiating unit or the discharge pressure (P _ci ) of the compressor 2 is acquired from the start of control (step S01) and stored in the memory (step S02). . Then, the previous value Q _icndz (or P _ciz ) stored in the memory in the previous control cycle and the current value Q _icnd (or P _ci ) are compared (step S03), and Q _icnd ≧Q _icndz (or P _ci ≧P _ciz ) is established (step S03: YES), it is determined that the hot gas heating can be continued, and the current control cycle is terminated in response to the heating request (step S04).

Also, the previous value Q _icndz (or P _ciz ) and the current value Q _icnd (or P _ci ) are compared (step S03), and if Q _icnd ≧Q _icndz (or P _ci ≧P _ciz ) does not hold ( Step S03: NO), the heat dissipation amount (Q _out ) of the refrigerant described above is reduced (step S05), processing is performed to return to a state in which hot gas heating can be continued, and the current control cycle ends.

By performing the control shown in FIG. 6, a time chart as shown in FIG. 7 is obtained. FIG _. 7(a) shows the time-series change in the amount of heat radiation Q _icnd of the heat radiating section. , lowers Q _icnd . At this time, by lowering the output voltage of the air blower 13 and lowering the amount of air blown through the heat radiating section Ga, the absolute value of Q _icnd is reduced, but the time-series change is suppressed and Q _icnd becomes stable.

When the current value of Q _icnd is lower than the previous value, the amount of heat radiation (Q _out ) exceeds the amount of heat input (Q _comp ), and the conditions for continuing hot gas heating are broken. ing. Here, the continuation of hot gas heating is ensured by detecting this state and performing processing to reduce the amount of heat radiation (Q _out ).

By performing the process of step S05, the time-series change in the amount of heat radiation Q _icnd is stabilized, and when the conditions for continuing hot gas heating are maintained, the output voltage of the blower 13 is changed from V02 to V03 at a predetermined timing T02. It is controlled so that the amount of heat release Q _icnd corresponding to the heating request is appropriately obtained.

FIG. 7(b) shows the time-series change of the discharge pressure P _ci of the compressor 2. At the timing T10 when the current value of P _ci is lower than the previous value, the output voltage of the blower 13 is lowered from V11 to V12. to reduce Q _icnd (heat release Q _out ). At this time, the discharge pressure P _ci of the compressor 2 returns to a predetermined pressure by reducing the heat release amount Q _out and becomes a stable time series change state. The discharge pressure _Pci of the compressor 2 here is detected by the refrigerant pressure sensor Pr2 in the refrigerant circuit 20 shown in FIG.

Then, in order to meet the heating request in step S4 in the control flow of FIG. 3 or step S04 in the control flow of FIG. 7, control is performed to bring the blown air temperature (Thp) close to the target heating temperature (TCO).

When considering the continuity of hot gas heating for such a heating request, on the premise that the rotation speed of the compressor 2 is set near the upper limit, the target heating temperature (TCO) and the blow If the difference from the air temperature (Thp) is greater than the set value α1 (that is, (TCO−α1)>Tph, α1>0), the output voltage of the blower 13 is lowered to lower the heat release amount Q _out (O _icnd ). control to increase the continuity of hot gas heating. Then, on the same premise, when the blown air temperature (Tph) exceeds the target heating temperature (TCO) by the set value β (that is, TOC ≤ Thp-β, β > 0), the surplus capacity in that case is used. Then, the output voltage of the blower 13 is increased to increase the heat radiation amount Q _out (O _icnd ), thereby increasing the heat utilization efficiency during hot gas heating.

The control example shown in FIG. 8 combines the above-described control of the output voltage of the blower 13 (control of the heat radiating portion passage air blow amount Ga) and the above-described control for adjusting the flow rate ratio of the bypass flow path 3, and the hot gas heating continuation mode This is an example of executing

In this example, the amount of heat input Q _comp from the compressor 2 and the amount of heat radiation Q _icnd from the heat radiating unit are grasped from the start of control (step S10), and it is determined whether or not Q _comp ≧Q _icnd , which is the continuation condition for hot gas heating, holds. (step S11). If Q _comp ≧Q _icnd does not hold (step S11: NO), the output voltage of the blower 13 is lowered to continue the hot gas heating (step S16), thereby lowering the heat radiation amount Q _out .

Further, when Q _comp ≧Q _icnd , which is the continuation condition for hot gas heating in step S11, is satisfied (step S11: YES), the output voltage of the blower 13 is maintained (step S12), and according to the heating request , it is determined whether or not the blown air temperature (Thp) has reached the target heating temperature (TCO) (step S13). Here, if the blown-out air temperature (Thp) has not reached the target heating temperature (TCO) (step 13: NO), the flow rate ratio of the refrigerant flowing through the bypass flow path 3 is increased to decrease the heat radiation amount _Qout . (step S17). This increases the continuity of hot gas heating.

Then, in step S13, if the blown-out air temperature (Thp) has reached the target heating temperature (TCO) (step S17: YES), it is determined whether or not there is excess capacity (step S14), and there is no excess capacity. (step S14: NO), the state is maintained, and if there is a surplus capacity (step S14: YES), the flow rate ratio of the refrigerant flowing through the bypass flow path 3 is lowered (step S15), and the heat release amount Increase Q _out .

Note that the control device 4 provided in the vehicle air conditioner 1 is, as shown in FIG. configured as The control device 4 includes a CPU (Central Processing Unit) 41, a ROM (Read Only Memory) 42, a RAM (Random Access Memory) 43, an input/output I/F (Interface) 44, an in-vehicle communication I/F (Interface) 45, and the like. Each piece of hardware is interconnected via a bus 46 .

The CPU 41 controls the control device 4 by executing various programs stored in the ROM 42 . The ROM 42 is nonvolatile memory. For example, the ROM 42 stores programs executed by the CPU 41, data necessary for the CPU 41 to execute the programs, and the like. The RAM 43 is a main storage device such as DRAM (Dynamic Random Access Memory) or SRAM (Static Random Access Memory). For example, the RAM 43 functions as a work area used when the CPU 41 executes programs. The input/output I/F 44 is connected to various sensors and monitors installed in the EV, inputs data to the CPU 41 , and outputs data processed by the CPU 41 . The in-vehicle communication I/F 45 is connected to the in-vehicle network L to control data transmission/reception with other ECUs set in the EV.

The control device 4 receives data about the surrounding environmental information or data about the driving situation of the EV via the input/output I/F 44 and the in-vehicle communication I/F 45, and controls the above-described vehicle by the program executed by the CPU 41. The control of the air conditioner 1 is executed.

As described above, according to the embodiment of the present invention, it is possible to continue hot gas heating in the refrigerant circuit 20 including the compressor 2 of the heat pump. A sufficient amount of heating can be maintained with low power consumption without using an electric heater such as a heater. As a result, the practicability of the vehicle air conditioner using the heat pump can be improved.

Although the embodiments of the present invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments, and design modifications and the like are made within the scope of the present invention. is included in the present invention. In addition, each of the above-described embodiments can be combined by diverting each other's techniques unless there is a particular contradiction or problem in the purpose, configuration, or the like.

1: vehicle air conditioner, 2: compressor, 3: bypass flow path, 4: control device,
10: indoor air conditioning unit (air heating device), 10A: blowing layer, 10B: receiving layer,
11, 12: indoor heat exchanger (radiator), 13: blower,
14: air damper, 14A: air damper drive unit,
20: refrigerant circuit, 21: accumulator, 22 (22A to 22D): pressure reducing valve,
23 (23A to 23D): flow path switching valve, 24: external heat exchanger,
25: refrigerant-heat medium heat exchanger, 26: check valve,
30: heat medium circuit, 31: heat medium circulation pump,
41: CPU, 42: ROM, 43: RAM,
44: input/output I/F, 45: in-vehicle communication I/F, 46: bus,
L: In-vehicle network

Claims

A refrigerant circuit that includes at least a compressor and circulates a high-temperature refrigerant discharged from the compressor, an air heating device that heats air in a vehicle compartment by heat radiation of the refrigerant, and a control device that controls the amount of heat released by the refrigerant. A vehicle air conditioner comprising:
The vehicle air conditioner, wherein the control device has a hot gas heating continuation mode in which the amount of heat released by the refrigerant is equal to or less than the amount of heat input from the compressor.
The vehicle air conditioner according to claim 1, wherein the amount of heat input from the compressor is obtained from the power consumption of the compressor.
The air heating device blows air supplied into the vehicle interior to a heat radiating portion of the refrigerant circuit provided in the air heating device,
3. The vehicle air conditioner according to claim 1, wherein the control device controls the amount of air blown through the heat radiating section.
4. The vehicle air conditioner according to claim 3, wherein the control device reduces the amount of passing air when the amount of heat radiated from the heat radiating section is higher than the amount of heat input from the compressor.
The control device obtains the heat radiation amount (Q icnd ) of the heat radiating unit in each control cycle, and when the heat radiation amount (Q icnd ) obtained this time is lower than the heat radiation amount (Q icndz ) obtained last time, 5. The vehicle air conditioner according to claim 4, wherein the amount of passing air is reduced.
The control device acquires the discharge pressure (P ci ) of the compressor in each control cycle, and the discharge pressure (P 5. The vehicle air conditioner according to claim 4, wherein the amount of passing air is reduced when ci ) is low.
The vehicle air conditioner according to any one of claims 3 to 6, characterized in that the amount of passing air is controlled by the output of a blower in the air heating device or the opening of an air damper.
The refrigerant circuit includes a bypass flow path that bypasses circulation of the refrigerant to the air heating device,
The control device controls the amount of heat released by the refrigerant by controlling the flow rate ratio of the refrigerant flowing through the bypass channel and the refrigerant flowing through the air heating device. The vehicle air conditioner according to any one of the above.
The refrigerant circuit comprises a refrigerant-heat medium heat exchanger,
The vehicle air conditioner according to any one of claims 1 to 8, wherein the control device controls the heat release amount of the refrigerant by controlling the flow rate of the heat medium.
The vehicle air conditioner according to any one of claims 1 to 9, wherein the refrigerant circuit includes a refrigerant channel switching means capable of switching to a heat pump cycle.