A gas supplementing enthalpy increasing heat pump air conditioning integrated thermal management system for electric bus

Abstract

A kind of electric bus air supplementing enthalpy increasing heat pump integrated heat management air conditioning system and method, the high-pressure side of compressor is connected with four-way valve, outdoor core connects two branches: outdoor core is connected battery heat management heat exchanger by first check valve, battery heat management heat exchanger connects the inlet side of gas-liquid separator, the outlet side of gas-liquid separator is connected with the low-pressure side of compressor;Outdoor core is connected with main road expansion valve, the outlet of main road expansion valve is also divided into two ways, one way is connected battery heat management heat exchanger by second check valve;The other way is connected indoor core by air supplementing intermediate heat exchanger, indoor core is connected with four-way valve;The first end of the air supplementing intermediate heat exchanger is connected with the medium-pressure side of compressor, the second end is connected with main road expansion valve by heat exchange air supplementing expansion valve, the third end is directly connected with main road expansion valve, and the fourth end is connected with indoor core.The present application considers high-temperature refrigeration, normal temperature refrigeration, normal temperature heating, low-temperature heating, defrosting, refrigeration battery cooling heat management and heating battery cooling heat management and other functions.

Description

Technical Field

[0001] This invention belongs to the field of passenger vehicle thermal management, specifically relating to an integrated thermal management air conditioning system for electric buses using a supplementary gas enthalpy-increasing heat pump. Background Technology

[0002] Currently, the bus air conditioning industry offers limited product options for heating in cold regions. The gas-injection enthalpy-enhancing integrated thermal management air conditioning system, as a low-temperature heat pump air conditioning product, boasts advantages such as mature components, minimal attenuation of ultra-low temperature heating capacity, high energy efficiency in low-temperature heating, and high energy efficiency in normal-temperature heating. However, ultra-low temperature heat pump air conditioning systems have inherent challenges. Because they must accommodate a wide range of operating conditions including cooling, heating, and low-temperature heating, the system requires large-sized throttling components due to the high refrigerant mass flow rate under rated cooling and high-temperature cooling conditions. Conversely, during ultra-low temperature heating, the low evaporation temperature results in a small refrigerant mass flow rate, requiring smaller throttling components. Using a single throttling component can lead to reduced air conditioning reliability, poor low-temperature heating capacity, and inability to adjust. Furthermore, there are currently no integrated thermal management air conditioning systems in the industry that incorporate gas-injection enthalpy-enhancing technology.

[0003] In summary, the existing technical solutions and their technical shortcomings are as follows: (1) There are few low-temperature air replenishment and enthalpy increase systems for air conditioning in buses on the market, which cannot adapt to the cold northern regions.

[0004] (2) The existing gas replenishment and enthalpy enhancement system does not integrate the thermal management system function, and cannot adjust the thermal management of the whole vehicle.

[0005] (3) Existing air conditioning systems on the market use the same throttling element for both cooling and heating, resulting in low reliability, poor heating performance at low temperatures, inability to achieve precise low-temperature adjustment, and inability to adjust at ultra-low temperatures. Summary of the Invention

[0006] The technical problem to be solved by this invention is to address the issue that the mass flow rate of low-temperature heat pump systems in the prior art cannot be balanced, and aims to provide an integrated thermal management air conditioning system for electric buses using a gas-injection enthalpy-increasing heat pump.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solution: An integrated thermal management air conditioning system for electric buses using a supplementary gas enthalpy-increasing heat pump includes a compressor. A four-way valve is connected to the high-pressure side of the compressor, and the four-way valve connects to the compressor, an outdoor core, a gas-liquid separator, and an indoor core. The outdoor core is connected to two branches. One branch connects the outdoor core to a battery thermal management heat exchanger via a first one-way valve. The battery thermal management heat exchanger is connected to the inlet side of the gas-liquid separator, and the outlet side of the gas-liquid separator is connected to the low-pressure side of the compressor. The other branch connects the outdoor core to a main expansion valve. The outlet of the main expansion valve is also divided into two paths: one path connects to the battery thermal management heat exchanger via a second one-way valve; the other path connects to the indoor core via a supplementary gas intermediate heat exchanger. The indoor core is connected to the four-way valve. The first end of the gas-replenishing intermediate heat exchanger is connected to the intermediate pressure side of the compressor, the second end is connected to the main expansion valve through the heat exchange gas-replenishing expansion valve, the third end is directly connected to the main expansion valve, and the fourth end is connected to the indoor core. The first end connected to the intermediate pressure side of the compressor and the second end connected to the heat exchange gas-replenishing expansion valve are on the same side of the gas-replenishing intermediate heat exchanger; the third end connected to the main expansion valve and the fourth end connected to the indoor core are on the same side of the gas-replenishing intermediate heat exchanger.

[0008] The main expansion valve consists of two main expansion valves connected in parallel. During cooling, both main expansion valves are throttling elements and are controlled synchronously. During heating, one main expansion valve is a throttling element, and the other main expansion valve is a non-throttling element. The non-throttling element main expansion valve is connected to a third check valve.

[0009] A two-way dryer filter is connected to the refrigerant outlet side of the outdoor core.

[0010] A two-way filter is installed between the intermediate heat exchanger and the indoor core.

[0011] A heat exchanger expansion valve is installed on the inlet side of the battery thermal management heat exchanger.

[0012] A method for controlling an integrated thermal management air conditioning system using a gas-injection enthalpy-increasing heat pump for electric buses includes a refrigeration cycle control method and a heating cycle control method. The refrigeration cycle control method is as follows: the first inlet of the four-way valve is connected to the high-pressure side of the compressor, the second inlet is connected to the indoor core, the first outlet is connected to the outdoor core, and the second outlet is connected to the gas-liquid separator. At this time, the refrigerant discharged from the compressor enters the outdoor core through the four-way valve. After passing through the outdoor core, it splits into two branches. The first branch flows through the first one-way valve to the battery thermal management heat exchanger, and after heat exchange in the battery thermal management heat exchanger, it returns to the gas-liquid separator. The second branch: the refrigerant from the outdoor core outlet flows to the main expansion valve. At this time, both main expansion valves participate in throttling. After throttling, the refrigerant flows directly to the indoor core through the intermediate gas-replenishing heat exchanger. At this time, the heat exchange gas-replenishing expansion valve is closed, and after heat exchange in the indoor core, it flows into the gas-liquid separator. The refrigerant from the two branches merges and returns to the compressor. The heating cycle control method is as follows: the first inlet of the four-way valve is connected to the high-pressure side of the compressor, the second inlet is connected to the outdoor core, the first outlet is connected to the indoor core, and the second outlet is connected to the gas-liquid separator. At this time, after the refrigerant is discharged from the compressor, it passes through the indoor core and then enters the intermediate heat exchanger for gas injection. After passing through the intermediate heat exchanger for gas injection, it is divided into three paths. One path is throttled by the gas injection expansion valve and undergoes a second heat exchange in the intermediate heat exchanger for gas injection. After the second heat exchange, it enters the medium-pressure side of the compressor. The second path flows to the battery thermal management heat exchanger through the second one-way valve. After heat exchange in the battery thermal management heat exchanger, it returns to the gas-liquid separator. The third path flows to the main expansion valve. At this time, only one main expansion valve participates in throttling. After throttling, the refrigerant flows to the outdoor core. After heat exchange in the outdoor core, it flows into the gas-liquid separator. The two refrigerant paths in the gas-liquid separator merge and return to the low-pressure side of the compressor. After being compressed by the compressor, a new cycle begins.

[0013] Compared with existing technologies, this system integrates an ultra-low temperature gas injection and enthalpy enhancement system and a thermal management system, making it suitable for cold and low-temperature vehicles in northern regions. It also takes into account functions such as high-temperature cooling, normal-temperature cooling, normal-temperature heating, low-temperature heating, defrosting, cooling battery thermal management, and heating battery thermal management. It has the advantages of simple structure and easy implementation. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the refrigeration cycle control principle of the present invention; Figure 2 This is a schematic diagram of the heating cycle control principle of the present invention. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0017] like Figure 1 , Figure 2As shown, an integrated thermal management air conditioning system for electric buses using a supplementary gas enthalpy-increasing heat pump includes a compressor 1. A four-way valve 10 is connected to the high-pressure side of the compressor 1, and the four-way valve 10 connects to the compressor 1, an outdoor core 2, a gas-liquid separator 5, and an indoor core 9. The outdoor core 2 is connected to two branches. One branch connects the outdoor core 2 to a battery thermal management heat exchanger 4 via a first one-way valve 3. The battery thermal management heat exchanger 4 is connected to the inlet side of the gas-liquid separator 5, and the outlet side of the gas-liquid separator 5 is connected to the low-pressure side of the compressor 1. The other branch connects the outdoor core 2 to a main expansion valve 6. The outlet of the main expansion valve 6 is also divided into two paths: one path connects to the battery thermal management heat exchanger 4 via a second one-way valve 11; the other path connects to the indoor core 9 via a supplementary gas intermediate heat exchanger 7. The indoor core 9 is connected to the four-way valve 10. The first end of the gas-replenishing intermediate heat exchanger 7 is connected to the intermediate pressure side of the compressor 1, the second end is connected to the main expansion valve 6 through the heat exchange gas-replenishing expansion valve 8, the third end is directly connected to the main expansion valve 6, and the fourth end is connected to the indoor core 9; wherein, the first end connected to the intermediate pressure side of the compressor 1 and the second end connected to the heat exchange gas-replenishing expansion valve 8 are on the same side of the gas-replenishing intermediate heat exchanger 7; the third end connected to the main expansion valve 6 and the fourth end connected to the indoor core 9 are on the same side of the gas-replenishing intermediate heat exchanger 7.

[0018] Furthermore, the main expansion valve consists of two main expansion valves 6 connected in parallel. During cooling, both main expansion valves 6 are throttling elements and are controlled synchronously. During heating, one main expansion valve 6 is a throttling element, and the other main expansion valve 6 is a non-throttling element. The non-throttling main expansion valve is connected to a third check valve 15 (during heating, the other main expansion valve 6 is cut off by the check valve, and no refrigerant passes through, so it does not participate in throttling). In this way, the present invention uses a check valve to control and also has the function of gas replenishment and enthalpy increase.

[0019] Furthermore, a two-way dryer filter 12 is connected to the refrigerant outlet side of the outdoor core 2.

[0020] Furthermore, a two-way filter 13 is installed between the gas-replenishing intermediate heat exchanger 7 and the indoor core 9.

[0021] Furthermore, a heat exchanger expansion valve 14 is provided on the inlet side of the battery thermal management heat exchanger 4. It should be noted that the battery thermal management heat exchanger 4 is provided with a water inlet and a water outlet, and the battery thermal management heat exchanger 4 has a cooling thermal management function. The battery thermal management heat exchanger 4 is existing technology.

[0022] A method for controlling an integrated thermal management air conditioning system using a gas-injection enthalpy-increasing heat pump for electric buses includes a refrigeration cycle control method and a heating cycle control method. The refrigeration cycle control method is as follows: the first inlet of the four-way valve 10 is connected to the high-pressure side of the compressor 1, the second inlet is connected to the indoor core 9, the first outlet is connected to the outdoor core 2, and the second outlet is connected to the gas-liquid separator 5. At this time, the refrigerant discharged from the compressor 1 enters the outdoor core 2 through the four-way valve 10. After passing through the outdoor core 2, it splits into two branches. The first branch flows through the first one-way valve 3 to the battery thermal management heat exchanger 4, and after heat exchange in the battery thermal management heat exchanger 4, it returns to the gas-liquid separator 5. The second branch flows from the outlet of the outdoor core 2 to the main expansion valve 6. At this time, both main expansion valves 6 participate in throttling. After throttling, the refrigerant flows directly to the indoor core 9 through the intermediate heat exchanger 7. At this time, the heat exchange and gas replenishment expansion valve 8 is closed, and the intermediate heat exchanger 7 does not participate, therefore it does not play a heat exchange role. After heat exchange in the indoor core 9, it flows into the gas-liquid separator 5. The refrigerant from the two branches merges and returns to the compressor 1.

[0023] The heating cycle control method is as follows: the first inlet of the four-way valve 10 is connected to the high-pressure side of the compressor 1, the second inlet is connected to the outdoor core 2, the first outlet is connected to the indoor core 9, and the second outlet is connected to the gas-liquid separator 5. At this time, after the refrigerant is discharged from the compressor 1, it passes through the indoor core 9 and then enters the intermediate heat exchanger 7. After passing through the intermediate heat exchanger 7, it splits into three paths. One path is throttled by the intermediate heat exchanger 7 and undergoes a second heat exchange, after which it enters the medium-pressure side of the compressor 1. The second path flows through the second one-way valve 11 to the battery thermal management heat exchanger 4 and returns to the gas-liquid separator 5 after heat exchange. The third path flows to the main expansion valve 6. At this time, only the main expansion valve 6 participates in throttling. After throttling, the refrigerant flows to the outdoor core 2 (due to the action of the third one-way valve 15, the refrigerant can only enter the outdoor core 2 through the throttling main expansion valve during this process). After heat exchange in the outdoor core 2, it flows into the gas-liquid separator 5. The two refrigerant paths in the gas-liquid separator 5 merge and return to the low-pressure side of the compressor 1. After being compressed by the compressor, a new cycle begins.

[0024] This invention employs an integrated thermal management system structure with gas replenishment and enthalpy enhancement, enabling low-temperature gas replenishment and enthalpy enhancement heating. Therefore, it possesses functions such as high-temperature cooling, normal-temperature cooling, normal-temperature heating, low-temperature heating, and defrosting. It also integrates battery thermal management functions, providing wide-range precise adjustment capabilities. The cooling, heating, and low-temperature heating control effects are more precise, efficient, simpler, and more reliable.

[0025] Therefore, this invention is applicable to low-temperature heat pump air conditioning systems, and can realize functions such as air conditioning system cooling, heating, ultra-low temperature heating, defrosting, and vehicle thermal management.

[0026] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several changes and improvements without departing from the overall concept of the present invention, and these should also be considered within the scope of protection of the present invention.

Claims

1. An integrated thermal management air conditioning system for electric buses using a supplementary gas enthalpy-increasing heat pump, characterized in that: The system includes a compressor (1), with a four-way valve (10) connected to the high-pressure side of the compressor (1). The four-way valve (10) is connected to the compressor (1), the outdoor core (2), the gas-liquid separator (5), and the indoor core (9). The outdoor core (2) is connected to two branches. One branch is: the outdoor core (2) is connected to the battery thermal management heat exchanger (4) through the first check valve (3). The battery thermal management heat exchanger (4) is connected to the inlet side of the gas-liquid separator (5), and the outlet side of the gas-liquid separator (5) is connected to the low-pressure side of the compressor (1). The other branch is: the outdoor core (2) is connected to the main expansion valve (6). The outlet of the main expansion valve (6) is also divided into two paths. One path is connected to the battery thermal management heat exchanger (4) through the second check valve (11). The other path is connected to the indoor core (9) through the intermediate gas exchanger (7). The indoor core (9) is connected to the four-way valve (10). The first end of the gas-replenishing intermediate heat exchanger (7) is connected to the medium-pressure side of the compressor (1), the second end is connected to the main expansion valve (6) through the heat exchange gas-replenishing expansion valve (8), the third end is directly connected to the main expansion valve (6), and the fourth end is connected to the indoor core (9); wherein, the first end connected to the medium-pressure side of the compressor (1) and the second end connected to the heat exchange gas-replenishing expansion valve (8) are on the same side of the gas-replenishing intermediate heat exchanger (7); the third end connected to the main expansion valve (6) and the fourth end connected to the indoor core (9) are on the same side of the gas-replenishing intermediate heat exchanger (7); The main expansion valve consists of two main expansion valves (6) connected in parallel. During cooling, both main expansion valves (6) are throttling elements and are controlled synchronously. During heating, one main expansion valve (6) is a throttling element and the other main expansion valve (6) is a non-throttling element. The non-throttling element main expansion valve is connected to the third check valve (15).

2. The integrated thermal management air conditioning system for electric buses with supplemental air enthalpy-increasing heat pumps according to claim 1, characterized in that: A two-way dryer filter (12) is connected to the refrigerant outlet side of the outdoor core (2).

3. The integrated thermal management air conditioning system for electric buses with supplemental air enthalpy-increasing heat pumps according to claim 1, characterized in that: A two-way filter (13) is installed between the gas-filling intermediate heat exchanger (7) and the indoor core (9).

4. The integrated thermal management air conditioning system for electric buses with supplemental air enthalpy-increasing heat pumps according to claim 1, characterized in that: A heat exchanger expansion valve (14) is provided on the inlet side of the battery thermal management heat exchanger (4).

5. A method for controlling an integrated thermal management air conditioning system for an electric bus using a supplementary gas enthalpy-increasing heat pump based on any one of claims 1-4, characterized in that: This includes refrigeration cycle control methods and heating cycle control methods; The refrigeration cycle control method is as follows: the first inlet of the four-way valve (10) is connected to the high-pressure side of the compressor (1), the second inlet is connected to the indoor core (9), the first outlet is connected to the outdoor core (2), and the second outlet is connected to the gas-liquid separator (5); at this time, after the refrigerant is discharged from the compressor (1), it enters the outdoor core (2) through the four-way valve (10). After passing through the outdoor core (2), it splits into two branches. The first branch is: it flows to the battery thermal management heat exchanger (4) through the first one-way valve (3), and then through the battery thermal management heat exchanger (4). After heat exchange, the refrigerant from the heat exchanger (4) returns to the gas-liquid separator (5); the second branch is: the refrigerant from the outlet of the outdoor core (2) flows to the main expansion valve (6). At this time, both main expansion valves (6) participate in throttling. After throttling, the refrigerant flows directly to the indoor core (9) through the intermediate heat exchanger (7). At this time, the heat exchange and gas replenishment expansion valve (8) is closed. After heat exchange in the indoor core (9), the refrigerant flows into the gas-liquid separator (5); the refrigerant from the two branches merges and returns to the compressor (1). The heating cycle control method is as follows: the first inlet of the four-way valve (10) is connected to the high-pressure side of the compressor (1), the second inlet is connected to the outdoor core (2), the first outlet is connected to the indoor core (9), and the second outlet is connected to the gas-liquid separator (5); at this time, after the refrigerant is discharged from the compressor (1) and passes through the indoor core (9), the refrigerant output from the indoor core (9) enters the gas-fuel intermediate heat exchanger (7), and after passing through the gas-fuel intermediate heat exchanger (7), it is divided into three paths. One path is throttled by the gas-fuel expansion valve (8) and then undergoes a second heat exchange in the gas-fuel intermediate heat exchanger (7). After the second heat exchange, it enters the gas-fuel intermediate heat exchanger (7). The first path flows into the medium-pressure side of the compressor (1); the second path flows through the second one-way valve (11) to the battery thermal management heat exchanger (4), and after heat exchange in the battery thermal management heat exchanger (4), it returns to the gas-liquid separator (5); the third path flows to the main expansion valve (6), at which time only one main expansion valve (6) participates in throttling. After throttling, the refrigerant flows to the outdoor core (2), and after heat exchange in the outdoor core (2), it flows into the gas-liquid separator (5). The two refrigerant paths in the gas-liquid separator (5) merge and return to the low-pressure side of the compressor (1). After being compressed by the compressor, a new cycle begins.

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