CN110816218A - Heat pump air conditioning system for vehicle - Google Patents

Heat pump air conditioning system for vehicle Download PDF

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Publication number
CN110816218A
CN110816218A CN201911312746.5A CN201911312746A CN110816218A CN 110816218 A CN110816218 A CN 110816218A CN 201911312746 A CN201911312746 A CN 201911312746A CN 110816218 A CN110816218 A CN 110816218A
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CN
China
Prior art keywords
heat exchanger
refrigerant
vehicle
outlet
inlet
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201911312746.5A
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Chinese (zh)
Inventor
葛勇超
覃峰
鱼苗
王平忠
王小波
周奕
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Chongqing Changan Automobile Co Ltd
Chongqing Changan New Energy Automobile Technology Co Ltd
Songz Automobile Air Conditioning Co Ltd
Original Assignee
Chongqing Changan Automobile Co Ltd
Chongqing Changan New Energy Automobile Technology Co Ltd
Songz Automobile Air Conditioning Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Chongqing Changan Automobile Co Ltd, Chongqing Changan New Energy Automobile Technology Co Ltd, Songz Automobile Air Conditioning Co Ltd filed Critical Chongqing Changan Automobile Co Ltd
Priority to CN201911312746.5A priority Critical patent/CN110816218A/en
Publication of CN110816218A publication Critical patent/CN110816218A/en
Pending legal-status Critical Current

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60HARRANGEMENTS OF HEATING, COOLING, VENTILATING OR OTHER AIR-TREATING DEVICES SPECIALLY ADAPTED FOR PASSENGER OR GOODS SPACES OF VEHICLES
    • B60H1/00Heating, cooling or ventilating [HVAC] devices
    • B60H1/02Heating, cooling or ventilating [HVAC] devices the heat being derived from the propulsion plant
    • B60H1/14Heating, cooling or ventilating [HVAC] devices the heat being derived from the propulsion plant otherwise than from cooling liquid of the plant, e.g. heat from the grease oil, the brakes, the transmission unit
    • B60H1/143Heating, cooling or ventilating [HVAC] devices the heat being derived from the propulsion plant otherwise than from cooling liquid of the plant, e.g. heat from the grease oil, the brakes, the transmission unit the heat being derived from cooling an electric component, e.g. electric motors, electric circuits, fuel cells or batteries

Abstract

The embodiment of the invention discloses a heat pump air-conditioning system for a vehicle. The vehicle heat pump air-conditioning system comprises a refrigerant loop and a heating element management loop, wherein the refrigerant loop comprises a compressor, an in-vehicle heat exchanger, a first throttling element, a second throttling element, an out-vehicle heat exchanger, a plate type heat exchanger, a liquid-gas separator, a coaxial pipe and a refrigerant pipeline; the heating element management loop comprises an electronic water pump, a kettle, a heating element and a cooling liquid pipeline; in the refrigerant loop, the heating capacity of the heat exchanger in the vehicle is improved by connecting the heat exchanger outside the vehicle and the plate heat exchanger in parallel; in the heating element management loop, heat generated by the heating element is recovered, so that the temperature of refrigerant gas at the inlet of the compressor is heated by utilizing waste heat, the specific volume of the refrigerant is reduced, and the circulating amount of the refrigerant is increased; the circulation quantity of the refrigerant is comprehensively increased, and the heating capacity of the system is improved.

Description

Heat pump air conditioning system for vehicle
Technical Field
The embodiment of the invention relates to the technical field of electric automobiles, in particular to a heat pump air-conditioning system for a vehicle.
Background
In recent years, with the vigorous popularization and use of electric energy, new energy automobiles such as pure electric vehicles are popularized and are more and more popular with people.
Heating in winter becomes a more prominent problem of new energy vehicles, and heat pump air conditioners with high energy efficiency are increasingly researched and applied. However, the currently used refrigerant R134a has a large specific heat capacity at low temperature, so that the refrigerant circulation volume of the heat pump system is greatly reduced under the low-temperature working condition, the heating performance of the system is seriously influenced, and the heat requirement in the passenger compartment cannot be met. Therefore, the recovery of the waste heat of the heating elements such as the electric control of the motor and the like becomes a better solution of the existing heat pump air conditioning system.
Disclosure of Invention
The embodiment of the invention provides a heat pump air-conditioning system for a vehicle, which is used for realizing the purposes of improving the temperature of a refrigerant by utilizing waste heat recovery and reducing the specific heat capacity of the refrigerant so as to improve the circulation quantity of the refrigerant.
In a first aspect, an embodiment of the present invention provides a heat pump air conditioning system for a vehicle, which includes a refrigerant circuit and a heating element management circuit, where the refrigerant circuit includes a compressor, an in-vehicle heat exchanger, a first throttling element, a second throttling element, an out-vehicle heat exchanger, a plate heat exchanger, a liquid-gas separator, a coaxial pipe, and a refrigerant pipeline; the heating element management loop comprises an electronic water pump, a kettle, a heating element and a cooling liquid pipeline.
In the refrigerant loop, the outlet of the compressor is connected with the inlet of the in-vehicle heat exchanger through a refrigerant pipeline, the outlet of the in-vehicle heat exchanger is divided into two paths after passing through the refrigerant pipeline, one path of the outlet passes through the first throttling element to be connected with the inlet of the out-vehicle heat exchanger, the other path of the outlet passes through the second throttling element to be connected with the first inlet of the plate heat exchanger, the outlet of the out-vehicle heat exchanger and the first outlet of the plate heat exchanger are connected with the inlet of the liquid-gas separator through the refrigerant pipeline, the outlet of the liquid-gas separator is connected with the first inlet of the coaxial pipe, and the first outlet of the coaxial pipe is connected with the.
In the heating element management loop, a second outlet of the plate heat exchanger is connected with an inlet of the kettle through a cooling flow passage inside the heating element; the outlet of the kettle is connected with the inlet of the electronic water pump through a cooling liquid pipeline; an outlet of the electronic water pump is connected with a second inlet of the plate heat exchanger through a cooling liquid pipeline; optionally, the outlet of the electronic water pump is further connected to the second inlet of the coaxial pipe through a cooling liquid pipeline; and a second outlet of the coaxial pipe is connected with an inlet of the kettle through the internal cooling circulation of the heating element.
Optionally, the first throttling element is an electronic expansion valve.
Optionally, the coaxial tube is an intermediate heat exchanger.
Optionally, the plate heat exchanger is turned on when the ambient temperature is lower than a preset temperature.
In a second aspect, the embodiment of the invention further provides an electric vehicle, which includes the vehicle air conditioning system.
Optionally, the heating element is a driving motor, a motor controller, a dc/dc converter, and a vehicle-mounted charging device of the electric vehicle.
The heat pump air-conditioning system for the vehicle in the embodiment of the invention comprises a refrigerant loop and a heating element management loop, wherein the refrigerant loop comprises a compressor, an in-vehicle heat exchanger, a first throttling element, a second throttling element, an out-vehicle heat exchanger, a plate type heat exchanger, a liquid-gas separator, a coaxial pipe and a refrigerant pipeline, and the parallel plate type heat exchanger improves the heating capacity of the in-vehicle heat exchanger. The heating element management loop comprises an electronic water pump, a kettle and a cooling liquid pipeline, heat of the heating element is recovered from the heating element management loop and exchanges heat with refrigerant on one side of the plate heat exchanger in the refrigerant loop, and the temperature of refrigerant gas entering an inlet of the compressor is increased, so that the specific heat capacity of the refrigerant is reduced, the circulation quantity of the heat exchanger in the vehicle is increased, and the heating quantity of the heat exchanger in the vehicle is increased.
Drawings
Fig. 1 is a schematic structural diagram of a heat pump air conditioning system for a vehicle according to a first embodiment of the present invention;
fig. 2 is a schematic structural diagram of a heat pump air conditioning system for a vehicle according to a second embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.
Example one
Fig. 1 is a schematic structural diagram of a heat pump air-conditioning system for a vehicle according to an embodiment of the present invention, and as shown in fig. 1, the heat pump air-conditioning system for a vehicle includes a refrigerant circuit and a heating element management circuit, where the refrigerant circuit includes a compressor 1, an in-vehicle heat exchanger 2, a first throttling element 3, a second throttling element 4, an out-vehicle heat exchanger 5, a plate heat exchanger 6, a liquid-gas separator 7, a coaxial pipe 8, and a refrigerant pipeline; the heating element management loop comprises an electronic water pump 9, a kettle 10, a heating element 11 and a cooling liquid pipeline.
Referring to fig. 1, in a refrigerant loop, an outlet of a compressor 1 is connected with an inlet of an in-vehicle heat exchanger 2 through a refrigerant pipeline, an outlet of the in-vehicle heat exchanger 2 is divided into two paths after passing through the refrigerant pipeline, one path is connected with an inlet of an out-vehicle heat exchanger 2 through a first throttling element 3, the other path is connected with a first inlet of a plate heat exchanger 6 through a second throttling element 4, an outlet of an out-vehicle heat exchanger 5 and a first outlet of the plate heat exchanger 6 are connected with an inlet of an liquid-gas separator 7, an outlet of the liquid-gas separator 7 is connected with a first inlet of a coaxial pipe 8, and a first outlet of the coaxial pipe 8 is.
With continued reference to fig. 1, in the heating element management circuit, the second outlet of the plate heat exchanger 6 is connected to the inlet of the kettle 9 via a cooling flow channel inside the heating element 11; the outlet of the kettle 9 is connected with the inlet of the electronic water pump 10 through a cooling liquid pipeline; an outlet of the electronic water pump 10 is connected with a first inlet of the plate heat exchanger 6 through a cooling liquid pipeline.
It should be noted that, the operation process of the system in the heating mode of the refrigerant is as follows: the low-temperature low-pressure refrigerant gas is changed into high-temperature high-pressure refrigerant gas through the compressor 1, the high-temperature high-pressure refrigerant gas is cooled and condensed through the heat released by the heat exchanger 2 in the vehicle to form refrigerant liquid, the refrigerant liquid entering the heat exchanger 5 outside the vehicle is adjusted through the first throttling element 3 to exchange heat with the external environment to form low-temperature low-pressure two-phase refrigerant, the two-phase refrigerant is further evaporated through the liquid-gas separator 7, and then the gas entering the compressor 1 is ensured through the coaxial pipe 8, so that the heating cycle under the low-temperature working condition is completed. Meanwhile, the plate heat exchanger 6 is connected in parallel to the exterior heat exchanger 5, refrigerant liquid discharged from the interior heat exchanger 2 enters the first inlet of the plate heat exchanger 6 through the second throttling element 4, and in the heating element management loop, after waste heat of the heating element 11 is recovered, the refrigerant liquid enters the second inlet of the plate heat exchanger 6 under the driving of the electronic water pump 9, so that the high-temperature refrigerant liquid in the plate heat exchanger 6 exchanges heat with the refrigerant in the plate heat exchanger 6, on one hand, the plate heat exchanger 6 and the exterior heat exchanger 5 perform heat exchange in different modes simultaneously, and the heating capacity of the interior heat exchanger 2 is improved. On the other hand, the coolant of a relatively high temperature in the plate heat exchanger 6 exchanges heat with the refrigerant in the plate heat exchanger 6, and the temperature of the refrigerant gas passing through the liquid separator 7 and the coaxial pipe 8 is increased, thereby reducing the specific heat capacity of the refrigerant, increasing the circulation amount in the refrigerant circulation process, and increasing the heating capacity of the in-vehicle heat exchanger 2. The heating capacity of the vehicle heat pump air conditioning system is comprehensively improved.
The heat pump air-conditioning system for the vehicle in the embodiment of the invention comprises a refrigerant loop and a heating element management loop, wherein the refrigerant loop comprises a compressor 1, an in-vehicle heat exchanger 2, a first throttling element 3, a second throttling element 4, an out-vehicle heat exchanger 5, a plate type heat exchanger 6, a liquid-gas separator 7, a coaxial pipe 8 and a refrigerant pipeline, and the parallel plate type heat exchanger 6 improves the heating capacity of the in-vehicle heat exchanger 2. The heating element management loop comprises an electronic water pump 9, a kettle 10, a heating element 11 and a cooling liquid pipeline, heat of the heating element is recovered in the heating element management loop and exchanges heat with refrigerant on one side of the plate heat exchanger 6 in the refrigerant loop, and the temperature of refrigerant gas entering an inlet of the compressor 1 is increased, so that the specific heat capacity of the refrigerant is reduced, the circulation quantity of the refrigerant is increased, and the heating quantity of the heat exchanger 2 in the vehicle is increased.
Example two
Fig. 2 is a schematic structural diagram of a heat pump air conditioning system for a vehicle according to a second embodiment of the present invention. The technical solution provided by this embodiment is further refined on the basis of the above technical solution, and optionally, as shown in fig. 2, the outlet of the electronic water pump 9 is further connected to the second inlet of the coaxial pipe 8 through a coolant pipe; the second outlet of the coaxial pipe 8 is connected to the inlet of the kettle 10 via a cooling channel inside the heating element 11.
On the basis of the above embodiment, in the heating element management circuit, the cooling liquid passes through the cooling liquid pipeline of the heating element and the kettle 10, the cooling liquid recovers the waste heat generated by the heating element, and then enters the coaxial pipe 8 under the driving of the electronic water pump 9, the refrigerant of the coaxial pipe 8 exchanges heat with the cooling liquid with higher temperature, so that the temperature of the refrigerant gas which exchanges heat through the coaxial pipe 8 and enters the inlet of the compressor 1 is increased, and the heat is exchanged between the cooling liquid and the refrigerant of the plate heat exchanger 6 in combination with the above embodiment, so that the specific heat capacity of the refrigerant is reduced, the circulation amount of the refrigerant in the refrigerant circuit is further increased, and the heating amount generated by the heat pump air-conditioning system for the vehicle is increased.
Optionally, the first throttling element 3 and the second throttling element 4 are both electronic expansion valves.
It should be noted that the electronic expansion valve has an incomparable excellent characteristic compared with a thermostatic expansion valve, when the temperature is lower, the pressure change of the temperature sensing medium inside the thermostatic expansion valve is greatly reduced, and the adjusting function of the electronic expansion valve is affected, and under the environment of lower temperature, the internal temperature and pressure sensor of the electronic expansion valve can accurately reflect the change of excessive heat, and can provide better flow adjustment.
Optionally, the coaxial pipe 8 is an intermediate heat exchanger.
The coaxial pipe 8 is equivalent to an internal heat exchanger, the areas of the coaxial pipe 8 where the higher-temperature cooling liquid and the low-temperature refrigerant gas flow are separated from each other, the flowing directions are opposite, intermediate heat exchange is realized, and the residual heat recovered from the heating element enables the temperature of the refrigerant gas entering the inlet of the compressor 1 in the refrigerant circuit to be increased through the coaxial pipe 8, so that the specific heat capacity of the refrigerant is reduced, the circulation amount of the refrigerant is increased, and the heating capacity generated by the heat pump air conditioning system for the vehicle is increased.
Optionally, the plate heat exchanger 6 is turned on when the ambient temperature is lower than a preset temperature.
Wherein, normally, the plate heat exchanger 6 is opened in a cooling condition. In this embodiment, the plate heat exchanger 6 is used under the working condition of the heat pump by switching the coolant side loop and detecting the temperature and the pressure through the temperature and pressure sensor, for example, in winter, the electronic expansion valve controls the plate heat exchanger 6 to be opened, so as to exchange heat with the coolant at a higher temperature in the heating management loop, thereby further improving the circulation amount of the refrigerant.
The heat pump air-conditioning system for the vehicle in the embodiment of the invention comprises a refrigerant loop and a heating element management loop, wherein the refrigerant loop comprises a compressor 1, an in-vehicle heat exchanger 2, a first throttling element 3, a second throttling element 4, an out-vehicle heat exchanger 5, a plate heat exchanger 6, a liquid-gas separator 7, a coaxial pipe 8 and a refrigerant pipeline, and the heating capacity of the in-vehicle heat exchanger 2 is improved in the refrigerant loop by connecting the out-vehicle heat exchanger 5 and the plate heat exchanger 6 in parallel; the heating element management loop comprises an electronic water pump 9, a kettle 10 and a cooling liquid pipeline, wherein in the heating element management loop, an outlet of the electronic water pump 9 is respectively connected with a second inlet of the coaxial pipe 8 and a first outlet of the plate type heat exchanger 6, the temperature of a refrigerant at an inlet of the compressor 1 is heated by waste heat generated by the heating element, the specific volume of the refrigerant is reduced, the circulation volume of the refrigerant is increased, the problem that the specific heat capacity of the refrigerant is larger under a low-temperature working condition in the prior art is solved, the circulation volume of the refrigerant is comprehensively increased, and the heating capacity of the system is increased.
The embodiment of the invention also provides an electric automobile which comprises the vehicle heat pump air-conditioning system provided by the embodiment. Optionally, the heating element in the electric vehicle is a driving motor, a motor controller, a dc/dc converter, and a vehicle-mounted charging device.
The vehicle heat pump air-conditioning system is adopted to recover the waste heat of heating elements such as the driving motor and/or the motor controller and the like, and reduce the specific heat capacity of the refrigerant at the inlet of the compressor 1, so that the circulation quantity of the refrigerant is improved, and the heating quantity of the heat pump system is increased, so that the difference value between the heating quantity in the electric automobile and the heat required by a passenger compartment is smaller and smaller, and the heating requirement of passengers in the passenger compartment of the electric automobile in winter is met.
It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims (7)

1. A heat pump air conditioning system for a vehicle, comprising: the system comprises a refrigerant circuit and a heating element management circuit, wherein the refrigerant circuit comprises a compressor, an in-vehicle heat exchanger, a first throttling element, a second throttling element, an out-vehicle heat exchanger, a plate type heat exchanger, a liquid-gas separator, a coaxial pipe and a refrigerant pipeline; the heating element management loop comprises an electronic water pump, a kettle, a heating element and a cooling liquid pipeline;
in the refrigerant loop, an outlet of the compressor is connected with an inlet of the in-vehicle heat exchanger through a refrigerant pipeline, an outlet of the in-vehicle heat exchanger is divided into two paths after passing through the refrigerant pipeline, one path of the outlet is connected with an inlet of the out-vehicle heat exchanger through the first throttling element, the other path of the outlet is connected with a first inlet of the plate heat exchanger through the second throttling element, an outlet of the out-vehicle heat exchanger and a first outlet of the plate heat exchanger are connected with an inlet of the liquid-gas separator through refrigerant pipelines, an outlet of the liquid-gas separator is connected with a first inlet of the coaxial pipe, and a first outlet of the coaxial pipe is connected with an inlet of the compressor through a refrigerant pipeline;
in the heating element management loop, a second outlet of the plate heat exchanger is connected with an inlet of the kettle through a cooling flow passage in the heating element; the outlet of the kettle is connected with the inlet of the electronic water pump through a cooling liquid pipeline; and the outlet of the electronic water pump is connected with the second inlet of the plate heat exchanger through a cooling liquid pipeline.
2. The heat pump air-conditioning system for vehicles of claim 1, wherein the outlet of the electronic water pump is further connected with the second inlet of the coaxial pipe through a coolant pipe; and a second outlet of the coaxial pipe is connected with an inlet of the kettle through a cooling flow passage in the heating element.
3. The heat pump air conditioning system for vehicles of claim 1, wherein the first throttling element is an electronic expansion valve.
4. The heat pump air conditioning system for vehicles of claim 1, wherein the coaxial pipe is an intermediate heat exchanger.
5. The heat pump air-conditioning system for vehicles as claimed in claim 1, wherein the plate heat exchanger is turned on when the ambient temperature is lower than a preset temperature.
6. An electric vehicle characterized by comprising the heat pump air conditioning system for vehicle of any one of claims 1 to 5.
7. The electric vehicle according to claim 6, wherein the heating element is a driving motor, a motor controller, a DC/DC converter, and an on-vehicle charging device of the electric vehicle.
CN201911312746.5A 2019-12-18 2019-12-18 Heat pump air conditioning system for vehicle Pending CN110816218A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201911312746.5A CN110816218A (en) 2019-12-18 2019-12-18 Heat pump air conditioning system for vehicle

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201911312746.5A CN110816218A (en) 2019-12-18 2019-12-18 Heat pump air conditioning system for vehicle

Publications (1)

Publication Number Publication Date
CN110816218A true CN110816218A (en) 2020-02-21

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113246686A (en) * 2021-05-30 2021-08-13 重庆长安汽车股份有限公司 Integrated thermal management system of pure electric vehicle and pure electric vehicle
WO2021239137A1 (en) * 2020-05-29 2021-12-02 杭州三花研究院有限公司 Heat management system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021239137A1 (en) * 2020-05-29 2021-12-02 杭州三花研究院有限公司 Heat management system
CN113246686A (en) * 2021-05-30 2021-08-13 重庆长安汽车股份有限公司 Integrated thermal management system of pure electric vehicle and pure electric vehicle

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