JP2023087937A - Vehicle air-conditioning device - Google Patents

Abstract

To provide a vehicle air-conditioning device capable of appropriately aligning with vehicle behavior while curbing increases in a size of a device configuration and a cost.SOLUTION: A vehicle air-conditioning device is mounted on a vehicle comprising a battery and a motor which generates either driving force or regenerative braking force through supplying or receiving electric power to and from the battery. The vehicle air-conditioning device has a control unit and an air-conditioning unit 19. The control unit controls supply and reception of the electric power between the motor and the battery and the air-conditioning unit 19. The air-conditioning unit 19 has a compressor 52 which compresses a heat medium and a heater 58 which heats the heat medium sucked into the compressor 52. The control unit activates the heater 58 and increases a rotation speed of the compressor 52 when the electric power generated through regenerative operation of the motor is greater than the electric power that can be charged to the battery.SELECTED DRAWING: Figure 2

Description

The present invention relates to a vehicle air conditioner.

Conventionally, in a vehicle equipped with a motor that generates regenerative braking force and a battery that is charged with electric power generated by the motor's regenerative operation, when the electric power generated by the motor's regeneration is greater than the electric power that can be charged in the battery, the electric power A vehicle control device that increases the power consumption of a load is known (see Patent Document 1, for example). This vehicle control device prevents the vehicle occupant from feeling uncomfortable with braking behavior due to fluctuations in the regenerative braking force by avoiding the amount of regeneration of the motor being limited by the amount of charge in the battery.

JP 2015-162947 A

By the way, the vehicle control device described above includes an air conditioning system with separate cooling and heating devices, and when the power consumption of the electric load is increased, the cooling device and the heating device are arranged so that the sensible temperature of the vehicle occupants does not change. to increase the output of However, when separate cooling and heating devices are provided, the configuration of the air conditioning system becomes large and expensive.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a vehicle air conditioner that can appropriately cooperate with vehicle behavior while suppressing an increase in the size and cost of the device configuration.

In order to solve the above problems and achieve the object, the present invention employs the following aspects.
(1) A vehicle air conditioner according to one aspect of the present invention (for example, the vehicle air conditioner 10 in the embodiment) provides a power storage device (for example, the battery 13 in the embodiment) and power exchange with the power storage device. It is mounted on a vehicle (for example, vehicle 1 in the embodiment) equipped with a rotating electric machine (for example, motor 11 in the embodiment) that generates either driving force or regenerative braking force, and power is supplied from the power storage device. an air conditioner (for example, the air conditioner 19 in the embodiment) that operates by a controller (for example, the controller 17 in the embodiment) that transfers power between the rotating electric machine and the power storage device and controls the air conditioner; , wherein the air conditioner includes a flow path for circulating a heat medium (for example, heat medium flow path 51 in the embodiment), a compressor for compressing the heat medium (for example, compressor 52 in the embodiment), A first heat exchanger (for example, the outdoor heat exchanger 54 in the embodiment) that exchanges heat between the heat medium and the outside air, and heat exchange between the heat medium and the air that is sent to the interior of the vehicle. a second heat exchanger (for example, the evaporator 33 and the condenser 34 in the embodiment), the pressure reduction of the heat medium flowing from the second heat exchanger to the first heat exchanger, and the At least one pressure reducer (for example, the first expansion valve 53 and the second expansion valve 56 in the embodiment) that performs any one of decompression of the heat medium flowing to the second heat exchanger, and is sucked into the compressor a heater (for example, the heater 58 in the embodiment) that heats the heat medium, and the control device controls that the electric power generated by the regenerative operation of the rotating electric machine is higher than the electric power that can be charged to the power storage device. If so, the heater is activated and the compressor speed is increased.

(2) In the vehicle air conditioner described in (1) above, the control device controls the target rotation speed of the compressor after the heater is actuated (for example, the rotation speed (target rotation speed) Nca in the embodiment). may be controlled to be greater than the rotation speed of the compressor before the heater is activated (for example, the rotation speed Nc in the embodiment).

(3) In the vehicle air conditioner described in (2) above, the controller controls the operation target of the air conditioner (for example, the target heating capacity or the target cooling capacity in the embodiment) before and after the heater is operated. may be controlled to maintain

According to (1) above, the control device increases the specific volume of the heat medium sucked into the compressor by heating the heat medium with the heater. The control device increases the rotation speed of the compressor so as to compensate for the decrease in the suction flow rate (mass flow rate) of the heat medium per revolution of the compressor as the specific volume of the heat medium increases. Since the power consumption increases as the rotation speed of the compressor increases, even if the power generated during the regenerative operation of the rotating electrical machine is greater than the power that can be charged in the power storage device, the regenerative operation of the rotating electrical machine is not restricted. Desired regenerative braking force can be secured.

In the case of (2) above, the control device can appropriately increase the power consumption of the compressor by controlling the output of the heater so that the rotational speed of the compressor increases according to the target rotational speed.

In the case of (3) above, even if the operating state of the air conditioner is changed by operating the heater and increasing the rotation speed of the compressor, the control device may set the target heating capacity or the target cooling capacity, for example. Air conditioner operating targets can be maintained.

1 is a configuration diagram of a vehicle equipped with a vehicle air conditioner according to an embodiment of the present invention; FIG. The block diagram of the air conditioner in embodiment of this invention. 4 is a flow chart showing the operation of the air conditioner in the embodiment of the present invention; FIG. 2 is a Mollier diagram with pressure and specific enthalpy showing the operation of an air conditioner in an embodiment of the invention.

A vehicle air conditioner 10 according to an embodiment of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a configuration diagram of a vehicle 1 equipped with a vehicle air conditioner 10 according to the embodiment.
As shown in FIG. 1, a vehicle air conditioner 10 of the embodiment is mounted in a vehicle 1 such as an electric vehicle. Electric vehicles include electric vehicles, hybrid vehicles, fuel cell vehicles, and the like. An electric vehicle is driven by a battery as a power source. A hybrid vehicle is driven by a battery and an internal combustion engine as power sources. A fuel cell vehicle is driven by a fuel cell as a power source.

The vehicle 1 includes, for example, a motor 11, a battery 13, a power conversion device 15, a control device 17, and an air conditioner 19. In addition, the vehicle air conditioner 10 of the embodiment includes, for example, a control device 17 and an air conditioner 19 .
The motor 11 is, for example, a three-phase AC brushless DC motor or the like. The motor 11 is for running and driving the vehicle 1, and generates rotational driving force by performing a power running operation with electric power supplied from the battery 13 through the power conversion device 15. FIG. The motor 11 generates electric power by performing regenerative operation with rotational power input to the rotating shaft from the wheel side. Electric power generated by the regenerative operation of the motor 11 is supplied to the battery 13 via the power converter 15 . The motor 11 generates regenerative braking force on the wheel side by regenerative operation.

The power conversion device 15 includes, for example, a power conversion circuit that converts power between DC and AC, and boosts and steps down DC power. The power converter 15 controls the operation of the motor 11 .
For example, when the motor 11 is powered, the power conversion device 15 converts DC power input from the battery 13 into AC power and supplies the AC power to the motor 11 . The power conversion device 15 generates rotational driving force by sequentially commutating the energization of the multiple phases of the motor 11 .
For example, when the motor 11 is regenerating, the power conversion device 15 converts AC power input from the motor 11 into DC power by a switching operation synchronized with the rotation of the motor 11 . The power conversion device 15 supplies DC power converted from AC power to the battery 13 .
The battery 13 is, for example, a high voltage battery that is the power source of the vehicle 1 . The battery 13 includes a battery case and a plurality of battery modules housed in the battery case. A battery module comprises a plurality of battery cells connected in series or in parallel.

The control device 17 comprehensively controls the operation of the vehicle 1 .
The control device 17 is, for example, a software functional unit that functions when a predetermined program is executed by a processor such as a CPU (Central Processing Unit). The software function unit is an ECU (Electronic Control Unit) comprising a processor such as a CPU, a ROM (Read Only Memory) for storing programs, a RAM (Random Access Memory) for temporarily storing data, and an electronic circuit such as a timer. . At least part of the control device 17 may be an integrated circuit such as an LSI (Large Scale Integration).

FIG. 2 is a configuration diagram of the air conditioner 19 in the embodiment. The air conditioner 19 operates by power supply from the battery 13 .
As shown in FIG. 2, the air conditioner 19 includes an air conditioning unit 21 and a heat pump unit 23, for example.
The air conditioning unit 21 includes, for example, a duct 31 , a blower 32 , an evaporator 33 , a condenser 34 , an air mix door 35 and an auxiliary heater 36 .
The duct 31 circulates the air taken in from the outside of the vehicle 1 or the vehicle interior. The duct 31 is formed with, for example, an inside air intake port 41a, an outside air intake port 41b, and a first outlet 42a and a second outlet 42b. The inside air intake port 41a takes in the inside air by communicating with the interior of the vehicle. The outside air intake port 41b takes in the outside air by communicating with the outside of the vehicle 1 . The first air outlet 42a blows air from the dashboard of the vehicle 1 toward the occupant, for example. The second air outlet 42b blows air from, for example, the upper portion of the dashboard of the vehicle 1 toward the front window.

The duct 31 includes an inside air door 43a that opens and closes the inside air intake 41a and an outside air door 43b that opens and closes the outside air intake 41b. The control device 17 controls the degree of opening of the inside air door 43a and the outside air door 43b. The control device 17 controls the flow ratio of the inside air and the outside air taken into the duct 31 according to the respective opening degrees of the inside air door 43a and the outside air door 43b.
The duct 31 includes a first door 44a that opens and closes the first outlet 42a and a second door 44b that opens and closes the second outlet 42b. The degree of opening of each of the first door 44a and the second door 44b is controlled by the controller 17 . The control device 17 controls the flow rate ratio of the air blown into the vehicle interior from the first blower outlet 42a and the second blower outlet 42b according to the respective opening degrees of the first door 44a and the second door 44b.

The blower 32 is arranged upstream in the duct 31 . The blower 32 blows out the air taken in from the inside air intake port 41a and the outside air intake port 41b toward the downstream side according to the control by the control device 17 .
An evaporator 33 is arranged downstream of the blower 32 in the duct 31 . The evaporator 33 cools the air passing through the evaporator 33 by heat exchange between the low-pressure heat medium flowing inside and the air in the duct 31, for example, heat absorption when the heat medium evaporates.

A condenser (condenser) 34 is arranged downstream of the evaporator 33 in the duct 31 . The condenser 34 heats the air passing through the condenser 34 by heat exchange between the high-temperature and high-pressure heat medium flowing inside and the air in the duct 31, for example, heat generated when the heat medium condenses.
The air mix door 35 is arranged upstream of the condenser 34 in the duct 31 . The air mix door 35 rotates between a heating position that opens an air passage from the evaporator 33 to the condenser 34 in the duct 31 and a cooling position that opens an air passage that bypasses the condenser 34 from the evaporator 33 in the duct 31. do. Rotation of the air mix door 35 is controlled by the controller 17 . The control device 17 controls the flow ratio of the air that passes through the condenser 34 and the air that bypasses the condenser 34 in the air that has passed through the evaporator 33 according to the rotation angle of the air mix door 35 .
The auxiliary heater 36 is arranged downstream of the condenser 34 in the duct 31 . The auxiliary heater 36 is, for example, a PTC (Positive Temperature Coefficient) heater or the like. Auxiliary heater 36 auxiliary heats the air passing through condenser 34 .

The heat pump unit 23 includes, for example, a heat medium flow path 51, the above-described evaporator 33 and condenser 34, a compressor (compressor) 52, a first expansion valve 53, an outdoor heat exchanger 54, a three-way valve 55, A second expansion valve 56 , a gas-liquid separator 57 , a heater 58 , a plurality of temperature sensors 59 and a plurality of pressure sensors 60 are provided.
The heat medium flow path 51 circulates the heat medium, which is the working medium of the heat pump.
A compressor (compressor) 52 is arranged between the condenser 34 and the gas-liquid separator 57 in the heat medium flow path 51 . The compressor 52 is, for example, an electric compressor. The compressor 52 sucks the gas-phase heat medium from the gas-liquid separator 57 . The compressor 52 compresses the heat medium to discharge the heat medium at high temperature and high pressure toward the condenser 34 .

The first expansion valve 53 is arranged between the condenser 34 and the outdoor heat exchanger 54 in the heat medium flow path 51 . The first expansion valve 53 is a so-called throttle valve and an electronic expansion valve whose opening is controlled by the control device 17 . The opening degree of the first expansion valve 53 is set to a predetermined opening degree during the heating operation of the air conditioner 19, and is set to a fully open state during the cooling operation and the defrosting operation of the air conditioner 19.
During heating operation, the first expansion valve 53 decompresses and expands the heat medium that has flowed out of the condenser 34 , thereby directing the heat medium in a gas-liquid two-phase state at a lower temperature and pressure than the outside air temperature toward the outdoor heat exchanger 54 . and send it out. During cooling operation and defrosting operation, the first expansion valve 53 passes the heat medium flowing out of the condenser 34 without changing its state, thereby sending the heat medium in a high temperature state toward the outdoor heat exchanger 54 .

The outdoor heat exchanger 54 is arranged between the first expansion valve 53 and the three-way valve 55 in the heat medium flow path 51 . The outdoor heat exchanger 54 exchanges heat between the internal heat medium and the atmosphere outside the vehicle outside the vehicle such as behind the front grill of the vehicle 1 .
During heating operation, the outdoor heat exchanger 54 raises the temperature of a heat medium having a lower temperature and a lower pressure than the outside air temperature by absorbing heat from the outside atmosphere of the vehicle. During the defrosting operation, the outdoor heat exchanger 54 defrosts and removes frost adhering to the outer surface of the outdoor heat exchanger 54 with a heat medium having a temperature higher than the outside air temperature. The outdoor heat exchanger 54 cools the heat medium having a higher temperature than the outside air temperature by radiating heat to the atmosphere outside the vehicle compartment during cooling operation.
The outdoor heat exchanger 54 includes, for example, a condenser fan 54a that cools the internal heat medium by blowing air from the outside.

The three-way valve 55 is arranged at a branch portion between the outdoor heat exchanger 54 and the second expansion valve 56 in the heat medium flow path 51 . The branched portion of the heat medium flow path 51 communicates via the branched flow path 61 with a confluence portion 63 provided between the evaporator 33 and the gas-liquid separator 57 in the heat medium flow path 51 . The three-way valve 55 switches the outdoor heat exchanger 54 side in the heat medium flow path 51 to the second expansion valve 56 side or the gas-liquid separator 57 side via the branch flow path 61 to communicate.
During heating operation and defrosting operation, the three-way valve 55 sends the heat medium flowing out of the outdoor heat exchanger 54 toward the confluence portion 63 on the gas-liquid separator 57 side through the branch flow path 61 . The three-way valve 55 sends out the heat medium that has flowed out of the outdoor heat exchanger 54 toward the second expansion valve 56 during cooling operation.

The second expansion valve 56 is arranged between the three-way valve 55 and the evaporator 33 in the heat medium flow path 51 . The second expansion valve 56 is a so-called throttle valve and an electronic expansion valve whose opening is controlled by the control device 17 . The second expansion valve 56 decompresses and expands the heat medium flowing out of the outdoor heat exchanger 54 in accordance with the degree of opening controlled by the control device 17, thereby producing a low-temperature and low-pressure gas-liquid two-phase heat medium. toward the evaporator 33.

The gas-liquid separator 57 is arranged between the confluence portion 63 in the heat medium flow path 51 and the compressor 52 . The gas-liquid separator 57 separates the gas component and the liquid component of the heat medium flowing out from the confluence portion 63 . The gas-liquid separator 57 sends out the gas-phase heat medium toward the heater 58 as the compressor 52 operates.
The heater 58 is arranged between the gas-liquid separator 57 and the compressor 52 in the heat medium flow path 51 . The heater 58 heats the gas-phase heat medium flowing from the gas-liquid separator 57 toward the compressor 52 under the control of the control device 17 . The heater 58 increases the specific volume of the heat medium sucked into the compressor 52 by heating the gaseous heat medium.

The multiple temperature sensors 59 are, for example, a first temperature sensor 59a, a second temperature sensor 59b, a third temperature sensor 59c, a fourth temperature sensor 59d and a fifth temperature sensor 59e.
The multiple pressure sensors 60 are, for example, a first pressure sensor 60a, a second pressure sensor 60b, a third pressure sensor 60c, a fourth pressure sensor 60d and a fifth pressure sensor 60e.
A first temperature sensor 59 a and a first pressure sensor 60 a are arranged between the heater 58 and the compressor 52 in the heat medium flow path 51 . The first temperature sensor 59a and the first pressure sensor 60a detect the temperature and pressure of the heat medium sucked into the compressor 52 and output signals representing the detected values of the temperature and pressure.

A second temperature sensor 59 b and a second pressure sensor 60 b are arranged between the compressor 52 and the condenser 34 in the heat medium flow path 51 . The second temperature sensor 59b and the second pressure sensor 60b detect the temperature and pressure of the heat medium discharged from the compressor 52 and flowing into the condenser 34, and output signals representing the detected values of the temperature and pressure.
The third temperature sensor 59 c and the third pressure sensor 60 c are arranged between the condenser 34 and the first expansion valve 53 in the heat medium flow path 51 . The third temperature sensor 59c and the third pressure sensor 60c detect the temperature and pressure of the heat medium flowing out from the condenser 34 toward the first expansion valve 53, and output signals of detected values of temperature and pressure.

A fourth temperature sensor 59 d and a fourth pressure sensor 60 d are arranged between the second expansion valve 56 and the evaporator 33 in the heat medium flow path 51 . A fourth temperature sensor 59d and a fourth pressure sensor 60d detect the temperature and pressure of the heat medium flowing into the evaporator 33 from the second expansion valve 56, and output signals representing the detected values of the temperature and pressure.
The fifth temperature sensor 59 e and the fifth pressure sensor 60 e are arranged between the evaporator 33 and the confluence portion 63 in the heat medium flow path 51 . A fifth temperature sensor 59e and a fifth pressure sensor 60e detect the temperature and pressure of the heat medium flowing out from the evaporator 33 toward the confluence portion 63, and output signals representing the detected values of the temperature and pressure.

Control operations performed by the control device 17 of the vehicle air conditioner 10 according to the embodiment will be described below.
FIG. 3 is a flow chart showing the operation of the air conditioner 19 in the embodiment.

First, in step S01 shown in FIG. 3, the control device 17 determines whether or not the air conditioner 19 is in operation.
If the determination result is "YES", the control device 17 advances the process to step S02. On the other hand, if the determination result is "NO", the control device 17 advances the process to END.
Next, in step S<b>02 , the control device 17 acquires the rotational speed Nc of the compressor 52 corresponding to the operation target of the air conditioner 19 . The operation target of the air conditioner 19 is, for example, a target heating capacity or a target cooling capacity. The control device 17 obtains the rotational speed Nc by, for example, searching map data of a predetermined correspondence relationship between the operating target according to the outside air temperature, the amount of solar radiation, the set temperature, etc., and the rotational speed Nc of the compressor 52. do.

Next, in step S03, the control device 17 acquires the temperature and pressure detection values of the heat medium sucked into the compressor 52 from the first temperature sensor 59a and the first pressure sensor 60a, and obtains the temperature and pressure detection values. A specific volume V of the heat medium corresponding to is acquired by a predetermined calculation or the like.
Next, in step S04, the control device 17 controls the weight flow rate of the heat medium based on the predetermined suction capacity S of the heat medium per revolution of the compressor 52, the rotation speed Hc, and the specific volume V. Obtain Gf (=Nc×S/V).

Next, in step S<b>05 , the control device 17 acquires the enthalpy change amount Δi of the heat medium in the duct 31 .
During the heating operation, the control device 17 outputs the detected values of the temperature and pressure of the heat medium flowing into the condenser 34 and the detected values of the temperature and pressure of the heat medium flowing out of the condenser 34 from the respective sensors 59b, 60b, 59c, 60c. Then, the enthalpy change amount Δi corresponding to the detected temperature and pressure values is obtained by a predetermined calculation or the like.
During the cooling operation, the control device 17 outputs the detected values of the temperature and pressure of the heat medium flowing into the evaporator 33 and the detected values of the temperature and pressure of the heat medium flowing out of the evaporator 33 from the respective sensors 59d, 60d, 59e and 60e. Then, the enthalpy change amount Δi corresponding to the detected temperature and pressure values is obtained by a predetermined calculation or the like.

Next, in step S06, the control device 17 determines whether or not there is a predetermined power consumption request.
If the determination result is "YES", the control device 17 advances the process to step S07. On the other hand, if the determination result is "NO", the control device 17 advances the process to END.
The predetermined power consumption request is, for example, when the power generated during the regenerative operation of the motor 11 is greater than the power that can be charged to the battery 13, and the like, so as not to restrict the regenerative operation of the motor 11. is to demand.

Next, in step S<b>07 , the control device 17 heats the gas-phase heat medium flowing from the gas-liquid separator 57 toward the compressor 52 by starting the operation of the heater 58 . The control device 17 increases the specific volume of the heat medium sucked into the compressor 52 by heating the vapor-phase heat medium with the heater 58 .
Next, in step S08, the control device 17 acquires the detected values of the temperature and pressure of the heat medium that is heated by the heater 58 and sucked into the compressor 52 from the first temperature sensor 59a and the first pressure sensor 60a. Then, the specific volume Va of the heat medium corresponding to the detected values of temperature and pressure is acquired by a predetermined calculation or the like.

Next, in step S09, the controller 17 acquires the enthalpy change amount Δia of the heat medium in the duct 31 when the heater 58 is in operation.
During the heating operation, the control device 17 outputs the detected values of the temperature and pressure of the heat medium flowing into the condenser 34 and the detected values of the temperature and pressure of the heat medium flowing out of the condenser 34 from the respective sensors 59b, 60b, 59c, 60c. Then, an enthalpy change amount Δia corresponding to the detected values of temperature and pressure is obtained by a predetermined calculation or the like.
During the cooling operation, the control device 17 outputs the detected values of the temperature and pressure of the heat medium flowing into the evaporator 33 and the detected values of the temperature and pressure of the heat medium flowing out of the evaporator 33 from the respective sensors 59d, 60d, 59e and 60e. Then, an enthalpy change amount Δia corresponding to the detected values of temperature and pressure is obtained by a predetermined calculation or the like.

Next, in step S10, the controller 17 sets the operation target of the air conditioner 19 before and after the heater 58 starts to operate without changing. For example, the controller 17 calculates the product of the weight flow rate Gf of the heat medium and the enthalpy change Δi before the heater 58 is activated, and the weight flow rate Gfa of the heat medium and the enthalpy change Δia after the heater 58 is activated. (Gf x Δi = Gfa x Δia).
Next, in step S11, the control device 17 controls the weight flow rate Gfa of the heat medium obtained based on step S10, the predetermined suction capacity S of the heat medium per revolution of the compressor 52, the heat medium and the specific volume Va of the compressor 52, the rotation speed (target rotation speed) Nca (=Gfa×Va/S) of the compressor 52 after the operation of the heater 58 is obtained.

Next, in step S12, the controller 17 determines whether or not the rotational speed Nca after the heater 58 is activated is greater than the rotational speed Nc before the heater 58 is activated.
If the determination result is "YES", the control device 17 advances the process to step S13. On the other hand, if the determination result is "NO", the control device 17 advances the process to step S14.
Then, in step S<b>13 , the control device 17 increases the output of the heater 58 . Then, the control device 17 advances the processing to the end.
Then, in step S<b>14 , the control device 17 maintains the output of the heater 58 . Then, the control device 17 advances the processing to the end.

FIG. 3 is a Mollier diagram by pressure and specific enthalpy showing the operation of the air conditioner 19 in an embodiment.
As shown in FIG. 3, in the air conditioner 19, when the heater 58 is in a non-operating state, the compressor 52 first transitions from the first phase ph1a of the gas phase VP to the second phase ph2a of the gas phase VP in the compression process. Next, the second phase ph2a of the gas phase VP transitions to the third phase ph3 of the liquid phase LP in the condensation process by the condenser 34 during heating operation or the outdoor heat exchanger 54 during cooling operation. Next, in the expansion stroke by the first expansion valve 53 during heating operation or the second expansion valve 56 during cooling operation, the third phase ph3 of the liquid phase LP transitions to the fourth phase ph4 of the gas-liquid two-phase LV. Next, in the evaporation process by the outdoor heat exchanger 54 during heating operation or the evaporator 33 during cooling operation, the gas-liquid two-phase LV fourth phase ph4 transitions to the gas-phase VP first phase pha1.

When the heating medium sucked into the compressor 52 is heated with the start of operation of the heater 58, the first phase ph1a changes to the post-heating first phase ph1b due to the increase in enthalpy due to the heating. Along with this, the specific volume of the heat medium increases from the specific volume sv1 in the first phase ph1a to the specific volume sv2 in the first phase ph1b after heating.
By maintaining the operation target of the air conditioner 19 before and after the start of operation of the heater 58, the control device 17 increases the rotation speed of the compressor 52 in the compression step after the operation of the heater 58, A transition is made from the phase ph1b to the post-heating second phase ph2b. Along with this, the enthalpy change Δia in the condensation process after the heater 58 is activated is greater than the enthalpy change Δi in the condensation process before the heater 58 is activated.
For example, when the heating of the heater 58 doubles the specific volume of the heat medium (=sv2/sv1) and the increase in enthalpy change is 30% (=(Δia−Δi)/Δi), the compressor The increase in the rotation speed of 52 is 54% (=(2-1.3)/1.3).

As described above, according to the vehicle air conditioner 10 of the embodiment, the control device 17 increases the specific volume of the heat medium sucked into the compressor 52 by heating the heat medium with the heater 58 . The control device 17 increases the rotation speed of the compressor 52 so as to compensate for the decrease in the suction flow rate (mass flow rate) of the heat medium per revolution of the compressor 52 as the specific volume of the heat medium increases. Since the power consumption increases as the rotation speed of the compressor 52 increases, even if the power generated during the regenerative operation of the motor 11 is greater than the power that can be charged in the battery 13, the regenerative operation of the motor 11 is not restricted. desired regenerative braking force can be ensured.

The controller 17 can appropriately increase the power consumption of the compressor 52 by controlling the output of the heater 58 so that the rotational speed of the compressor 52 increases according to the target rotational speed Nca.
Even when the control device 17 changes the operating state of the air conditioner 19 by operating the heater 58 and increasing the rotation speed of the compressor 52, for example, the target heating capacity or the target cooling capacity of the air conditioner 19 can be maintained.

(Modification)
Modifications of the embodiment will be described below. It should be noted that the same parts as those of the above-described embodiment are denoted by the same reference numerals, and descriptions thereof are omitted or simplified.

In the above-described embodiment, the heat pump unit 23 includes the heat medium flow path 51 that connects the compressor 52 to the outdoor heat exchanger 54 via the condenser 34 and the first expansion valve 53, but the heat pump unit 23 is not limited to this.
For example, the heat pump unit 23 may include a bypass channel that bypasses the condenser 34 and the first expansion valve 53 from the compressor 52 or bypasses the first expansion valve 53 from the condenser 34 and is connected to the outdoor heat exchanger 54 . . In these cases, the control device 17 circulates the heat medium from the compressor 52 through the heat medium flow path 51 to the outdoor heat exchanger 54 via the condenser 34 and the first expansion valve 53 in the heating operation, and in the cooling operation, A heat medium may be circulated through the bypass channel. In these cases, the degree of opening of the first expansion valve 53 may be fixed at a predetermined degree of opening, and the first expansion valve 53 may be a pressure reducer other than an electronic expansion valve.

In the above-described embodiment, the heat pump unit 23 includes the three-way valve 55, the branch flow path 61, and the confluence portion 63 in the heat medium flow path 51 between the outdoor heat exchanger 54 and the gas-liquid separator 57. It is not limited to this.
For example, the heat pump unit 23 has a detour flow path that bypasses the second expansion valve 56 and the evaporator 33 from the outdoor heat exchanger 54 and is connected to the gas-liquid separator 57 instead of at least the three-way valve 55 and the branch flow path 61. may be provided. In this case, the control device 17 circulates the heat medium through the bypass passage during heating operation, and circulates the heat medium through the heat medium passage 51 from the outdoor heat exchanger 54 to the second expansion valve 56 and the evaporator 33 during cooling operation. to the gas-liquid separator 57.

In the above-described embodiment, the heat pump unit 23 includes the first expansion valve 53 and the second expansion valve 56, but is not limited to this. There may be one expansion valve arranged in common to the flow paths of the to depressurize the heat medium.

Embodiments of the invention are provided by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and modifications can be made without departing from the scope of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, as well as the scope of the invention described in the claims and equivalents thereof.

DESCRIPTION OF SYMBOLS 1... Vehicle 10... Vehicle air conditioner 11... Motor (rotating electric machine) 13... Battery (storage device) 15... Power converter 17... Control apparatus 19... Air conditioner 31... Duct 31... Blower, 33... Evaporator (second heat exchanger), 34... Condenser (second heat exchanger), 51... Heat medium channel (channel), 52... Compressor, 53... First expansion valve (reducer ), 54... Outdoor heat exchanger (first heat exchanger), 55... Three-way valve, 56... Second expansion valve (reducer), 57... Gas-liquid separator, 58... Heater, 59... Temperature sensor, 60 … pressure sensor.

Claims (3)

an air conditioner mounted in a vehicle equipped with a power storage device and a rotating electric machine that generates either driving force or regenerative braking force by transferring power to and from the power storage device, and operated by power supply from the power storage device;
a control device for exchanging electric power between the rotating electric machine and the power storage device and for controlling the air conditioning device;
with
The air conditioner is
a channel for circulating the heat medium;
a compressor for compressing the heat medium;
a first heat exchanger for exchanging heat between the heat medium and the outside air;
a second heat exchanger for exchanging heat between the heat medium and the air sent into the interior of the vehicle;
at least one of depressurizing the heat medium flowing from the second heat exchanger to the first heat exchanger and depressurizing the heat medium flowing from the first heat exchanger to the second heat exchanger two pressure reducers;
a heater that heats the heat medium sucked into the compressor;
with
The control device operates the heater and increases the rotation speed of the compressor when the power generated by the regenerative operation of the rotating electric machine is larger than the power that can be charged in the power storage device. air conditioner. The control device is
2. The output of the heater is controlled so that the target rotation speed of the compressor after activation of the heater is higher than the rotation speed of the compressor before activation of the heater. air conditioner for vehicles. The control device is
3. The vehicle air conditioner according to claim 2, wherein control is performed so as to maintain an operation target of the air conditioner before and after operation of the heater.

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