Heat management dual system adopting refrigerant for direct cooling and direct heating and control mode

Abstract

The invention belongs to the technical field of power batteries, and particularly relates to a heat management dual system adopting direct cooling and direct heating of refrigerants and a control mode, and the heat management dual system comprises a first heat pipe system, a second heat pipe system and a battery pack, the first heat pipe system comprises a first compressor, a first exhaust pressure valve, a first temperature probe, a first battery pack inlet temperature probe, a first air-cooled condenser, a first drying filter, a first high-temperature electronic expansion valve, a first drying filter, a first group of normally-closed solenoid valves, a second group of normally-closed solenoid valves, a third group of normally-closed solenoid valves and a first one-way valve. According to the heat management dual system adopting direct cooling and direct heating of the refrigerant and the control mode, the low-temperature refrigerant or the high-temperature refrigerant directly enters the heat exchange plate of the battery pack and exchanges heat with a battery cell in the battery pack. Heat exchange is not carried out through other intermediate media any more, heat loss is reduced, and when the battery packs have refrigeration requirements, whether one system or two systems are opened is judged according to the number of the required battery packs.

Description

Technical Field

[0001] The present invention relates to the technical field of power batteries, and in particular to a thermal management dual system and a control method using a refrigerant for direct cooling and direct heating. Background Art

[0002] With the rapid development of the new energy industry, the demand for new energy vehicles is increasing, and the demand for power batteries is also increasing. Therefore, battery swap stations are set up one after another, and each battery swap station has multiple battery packs. When these batteries are charged, in order to improve their charging efficiency and reduce heat loss, the battery cell temperature during charging will be controlled within a certain range.

[0003] To ensure that the battery cell temperature is within an appropriate range when charging, the normally high-temperature circulating fluid in the cold plate is heat exchanged with the low-temperature refrigerant in the air-conditioning system to obtain a lower-temperature circulating fluid; the lower-temperature circulating fluid in the cold plate is heat exchanged with the high-temperature refrigerant in the air-conditioning system or with the heater to obtain a normally high-temperature circulating fluid, and the obtained lower-temperature or normally high-temperature circulating fluid enters the battery cold plate for secondary heat exchange with the battery, and is used to meet the cooling or heating requirements required to control the battery cell temperature when charging the battery.

[0004] The thermal management system equipped in each battery swap station is configured according to the maximum load required by the battery of this battery swap station. However, in reality, when only one battery pack is charging, the thermal management system also needs to run to meet the battery cell temperature. At this time, the load is very low. Even if the thermal management system is reduced to minimum capacity, it is still far greater than the load, so this will lead to a situation where a big horse is pulling a small cart. Summary of the invention

[0005] In order to overcome the above-mentioned defects of the prior art, the inventors conducted in-depth research and completed the present invention after paying a lot of creative work.

[0006] Specifically, the technical problem to be solved by the present invention is to provide a dual thermal management system and control method using refrigerant direct cooling and direct heating to solve the current problem of using an air conditioning system to control the temperature of the circulating fluid, and then exchanging heat between the circulating fluid and the battery to control the temperature of the battery core. The additional heat exchange increases energy loss, and the efficiency of using a heater to heat the circulating fluid from a low temperature to a normal high temperature is only about 80%. That is, 1kW of electrical energy only obtains 0.8kW of thermal energy, and 0.2kW of energy is consumed. There is only one battery pack to charge, and the load is low, which will cause the liquid refrigerant to return to the compressor after the thermal management system is running, resulting in liquid hammer; the lubricating oil cannot return to the oil chamber in time, resulting in poor lubrication of the compressor.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0008] A dual thermal management system and control method using refrigerant direct cooling and direct heating, a dual thermal management system using refrigerant direct cooling and direct heating, including a No. 1 heat pipe system, a No. 2 heat pipe system and a battery pack, the No. 1 heat pipe system includes a No. 1 compressor, a No. 1 exhaust pressure valve, a No. 1 temperature probe, a No. 1 battery pack inlet temperature probe, a No. 1 air-cooled condenser, a No. 1 drying filter, a No. 1 high-temperature electronic expansion valve, a No. 1 drying filter, a No. 1 group of normally closed solenoid valves, a No. 2 group of normally closed solenoid valves, a No. 3 group of normally closed solenoid valves and a No. 1 check valve, the No. 2 heat pipe system includes a No. 2 compressor, a No. 2 exhaust pressure valve, a No. 2 temperature probe, a No. 2 battery pack inlet temperature probe, a No. 2 air-cooled condenser, a No. 2 drying filter, a No. 2 high-temperature electronic expansion valve, a No. 2 drying filter, a No. 1 group of two normally closed solenoid valves, a No. 2 group of two normally closed solenoid valves, a No. 3 group of two normally closed solenoid valves and a No. 2 check valve;

[0009] The battery pack includes a No. 3 battery pack inlet temperature probe, a battery pack outlet temperature probe, a No. 1 battery pack, a No. 2 battery pack, a No. 3 battery pack, a No. 1 battery solenoid valve, a No. 2 battery solenoid valve and a No. 3 battery solenoid valve.

[0010] As an improved technical solution, the output end of the No. 1 compressor is fixedly connected to the input end of the No. 1 exhaust pressure valve through a pipeline, the output end of the No. 1 exhaust pressure valve is fixedly connected to the input end of the No. 1 exhaust temperature probe through a pipeline, the output end of the No. 1 exhaust temperature probe is fixedly connected to the input ends of the No. 1 air-cooled condenser and the No. 1 group of drying filters through pipelines, respectively, the output end of the No. 1 air-cooled condenser is fixedly connected to the input end of the No. 2 group of drying filters through a pipeline, the output end of the No. 2 group of drying filters is fixedly connected to the input end of the No. 1 low-temperature electronic expansion valve through a pipeline, and the output ends of the No. 1 low-temperature electronic expansion valve and the No. 1 group of normally closed solenoid valves are fixedly connected to the input end of the No. 1 check valve through pipelines.

[0011] As an improved technical solution, the output end of the No. 1 group of drying filters is fixedly connected to the input end of the No. 1 high-temperature electronic expansion valve through a pipeline, the output end of the No. 1 high-temperature electronic expansion valve is fixedly connected to the input ends of the No. 2 group of normally closed solenoid valves through pipelines, the output ends of the No. 2 group of normally closed solenoid valves and the No. 3 group of normally closed solenoid valves are fixedly connected to the input end of the No. 1 suction pressure valve through a pipeline, the output end of the No. 1 suction pressure valve is fixedly connected to the input end of the No. 1 suction temperature probe through a pipeline, and the output end of the No. 1 suction temperature probe is fixedly connected to the input end of the No. 1 compressor through a pipeline.

[0012] As an improved technical solution, the output end of the No. 2 compressor is fixedly connected to the input end of the No. 2 exhaust pressure valve through a pipeline, the output end of the No. 2 exhaust pressure valve is fixedly connected to the input end of the No. 2 exhaust temperature probe through a pipeline, the output end of the No. 2 exhaust temperature probe is fixedly connected to the input ends of the No. 2 air-cooled condenser and the No. 1 two-group drying filter through pipelines, respectively, the output end of the No. 1 air-cooled condenser is fixedly connected to the input end of the No. 2 two-group drying filter through a pipeline, the output end of the No. 2 two-group drying filter is fixedly connected to the input end of the No. 2 low-temperature electronic expansion valve through a pipeline, and the output ends of the No. 2 low-temperature electronic expansion valve and the No. 1 two-group normally closed solenoid valve are fixedly connected to the input end of the No. 2 check valve through pipelines.

[0013] As an improved technical solution, the output end of the No. 1 two-group drying filter is fixedly connected to the input end of the No. 2 high-temperature electronic expansion valve through a pipeline, the output end of the No. 2 high-temperature electronic expansion valve is fixedly connected to the input end of the No. 2 two-group normally closed solenoid valve through pipelines, the output ends of the No. 2 two-group normally closed solenoid valve and the No. 3 two-group normally closed solenoid valve are fixedly connected to the input end of the No. 2 suction pressure valve through a pipeline, the output end of the No. 2 suction pressure valve is fixedly connected to the input end of the No. 2 suction temperature probe through a pipeline, and the output end of the No. 2 suction temperature probe is fixedly connected to the input end of the No. 2 compressor through a pipeline.

[0014] As an improved technical solution, the input end of the No. 3 battery pack inlet temperature probe is fixedly connected to the output ends of the No. 2 one-way valve, the battery pack outlet temperature probe and the No. 1 one-way valve through a pipeline, and the output end of the battery pack outlet temperature probe is fixedly connected to the output end of the No. 3 group of normally closed battery solenoid valves through a pipeline.

[0015] As an improved technical solution, the output end of the inlet battery pack temperature probe is fixedly connected to the input ends of battery pack No. 1, battery pack No. 2 and battery pack No. 3 through a pipeline, the output end of the battery pack No. 1 is fixedly connected to the input end of the battery solenoid valve No. 1 through a pipeline, the output end of the battery pack No. 2 is fixedly connected to the input end of the battery solenoid valve No. 2 through a pipeline, the output end of the battery pack No. 3 is fixedly connected to the input end of the battery solenoid valve No. 3 through a pipeline, and the output ends of the battery solenoid valve No. 1, battery solenoid valve No. 2 and battery solenoid valve No. 3 are fixedly connected to the input end of the outlet battery pack temperature probe through a pipeline.

[0016] A thermal management control method using direct cooling and heating of refrigerant, any one of the thermal management methods using direct cooling and heating of refrigerant, if the battery has cooling or heating requirements, the system determines whether there is a fault, when the system determines that there is a fault, the fault is reset, when the system determines that there is no fault, when the battery pack value N of the cooling requirement is greater than or equal to 12, system one and system two operate simultaneously, when the battery pack value N of the cooling requirement is less than 12, the cumulative operating time of system one and system two is compared, and the system with the shorter cumulative operating time is started.

[0017] As an improved technical solution, when the direct cooling control system is running, the heat pipe system determines whether there is a fault. When the heat pipe system determines that there is a fault, the fault is reset. When the heat pipe system has no fault, the outlet temperature is set to 18 degrees Celsius, the normally closed solenoid valve of group 3 is opened, the heating management system is turned on, and the compressor is PID controlled according to the target temperature T: the low-temperature electronic expansion valve is controlled according to △T=0, and the dead zone is 0.5 for PID control. When the heat absorption: 1≤T﹤7 degrees Celsius and maintained for three minutes or T<one degree for thirty seconds, the high-temperature electronic expansion valve is opened, the normally closed solenoid valve of group 2 is opened, and the suction superheat T=8 is installed, the dead zone 1, and PID control is performed. When the heat absorption: 1≥T﹥7 degrees Celsius and maintained for three minutes or T>one degree for thirty seconds, the status quo is maintained.

[0018] As an improved technical solution, when the direct heating control system is started, the heat pipe system determines whether there is a fault. When the heat pipe system determines that there is a fault, the fault is reset. When the heat pipe system has no fault, the liquid outlet temperature is set to 50 degrees, the number one group of normally closed solenoid valves and the number three group of normally closed solenoid valves are opened, and the heating management system is turned on. The compressor is PID controlled according to the target temperature T, and the high-temperature electronic expansion valve is PID controlled according to the return air pressure of 1000kpa and the dead zone of 100kpa.

[0019] After adopting the above technical solution, the beneficial effects of the present invention are:

[0020] 1. The present invention adds a design for heating the battery during charging, through the coordinated use of the No. 3 battery pack inlet temperature probe and the battery pack outlet temperature probe with the No. 1 battery pack and the No. 1 battery solenoid valve, through the coordinated use of the No. 3 battery pack inlet temperature probe and the battery pack outlet temperature probe with the No. 2 battery pack and the No. 2 battery solenoid valve, through the coordinated use of the No. 3 battery pack inlet temperature probe and the battery pack outlet temperature probe with the No. 3 battery pack and the No. 3 battery solenoid valve, so that the low-temperature refrigerant or the high-temperature refrigerant directly enters the battery pack heat exchange plate to exchange heat with the battery cells in the battery pack, and no longer exchanges heat through other intermediate media, thereby reducing heat loss.

[0021] 2. The present invention meets the cooling and heating requirements of the battery pack when charging by increasing multiple heat exchanges. By using the No. 1 heat pipe system and the No. 2 heat pipe system in conjunction with the battery pack, the No. 1 high-temperature electronic expansion valve and the No. 3 group of normally closed solenoid valves are used in conjunction with the No. 2 high-temperature electronic expansion valve and the No. 3 group of normally closed solenoid valves, so that the refrigerant liquid entering the heat exchange plate completes latent heat exchange with the battery pack, and the state of the refrigerant liquid exiting the heat exchange plate is a gas-liquid two-phase refrigerant liquid, so that the refrigerant liquid undergoes multiple heat exchanges to cool or heat the battery pack.

[0022] 3. The present invention adds a design that allows the thermal management system to operate normally even at low loads, through the coordinated use of a group of normally closed solenoid valves No. 1 and a group of normally closed solenoid valves No. 3, the coordinated use of heat pipe system No. 1 and heat pipe system No. 2 with a battery pack, and the coordinated use of compressor No. 1 and compressor No. 2 with a high-temperature electronic expansion valve No. 1, so as to control the return air pressure at about 1000 kPa. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0024] Figure 1 It is a schematic diagram of the principle structure of the thermal management dual system using refrigerant direct cooling and direct heating and a control method of the thermal management dual system of the present invention.

[0025] Figure 2 It is a schematic diagram of the three-dimensional structure of the thermal management dual system using refrigerant direct cooling and direct heating and the control method of the thermal management dual system of the present invention.

[0026] Figure 3 This is a structural schematic diagram of the system valve arrangement diagram of the thermal management dual system and control method using refrigerant direct cooling and direct heating in the present invention.

[0027] Figure 4 It is a schematic diagram of the operation judgment structure of the single and double systems of the thermal management dual system and control method using refrigerant direct cooling and direct heating in the present invention.

[0028] Figure 5 It is a schematic diagram of the direct cooling logic control diagram structure of the thermal management dual system and control method using refrigerant direct cooling and direct heating in the present invention.

[0029] Figure 6 This is a schematic diagram of the direct heating control logic diagram structure of the thermal management dual system and control method using refrigerant direct cooling and direct heating in the present invention.

[0030] Description of reference numerals:

[0031] 1. Heat pipe system No. 1; 2. Heat pipe system No. 2; 3. Battery pack. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0034] At the same time, the meaning of "and / or" or "and / or" appearing in the full text includes three options. Taking "A and / or B" as an example, it includes option A, or option B, or a option in which both A and B are satisfied.

[0035] In addition, in the present invention, descriptions such as "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0036] like Figure 1 and Figure 4As shown together, the present embodiment provides a dual thermal management system and control method using refrigerant direct cooling and direct heating. The dual thermal management system and control method using refrigerant direct cooling and direct heating. A dual thermal management system using refrigerant direct cooling and direct heating includes a No. 1 heat pipe system 1, a No. 2 heat pipe system 2 and a battery pack 3. The No. 1 heat pipe system 1 includes a No. 1 compressor, a No. 1 exhaust pressure valve, a No. 1 temperature probe, a No. 1 battery pack inlet temperature probe, a No. 1 air-cooled condenser, a No. 1 drying filter, a No. 1 high-temperature electronic expansion valve, a No. 1 drying filter, a No. 1 group of normally closed solenoid valves, a No. 2 group of normally closed solenoid valves, a No. 3 group of normally closed solenoid valves and a No. 1 check valve. The No. 2 heat pipe system 2 includes a No. 2 compressor, a No. 2 exhaust pressure valve, a No. 2 temperature probe, a No. 2 battery pack inlet temperature probe, a No. 2 air-cooled condenser, a No. 2 drying filter, a No. 2 high-temperature electronic expansion valve, a No. 2 drying filter, a No. 1 group of two normally closed solenoid valves, a No. 2 group of two normally closed solenoid valves, a No. 3 group of two normally closed solenoid valves and a No. 2 check valve;

[0037] The battery pack 3 includes a No. 3 battery pack inlet temperature probe, a battery pack outlet temperature probe, a No. 1 battery pack, a No. 2 battery pack, a No. 3 battery pack, a No. 1 battery solenoid valve, a No. 2 battery solenoid valve and a No. 3 battery solenoid valve.

[0038] As an improved technical solution, the output end of the No. 1 compressor is fixedly connected to the input end of the No. 1 exhaust pressure valve through a pipeline, the output end of the No. 1 exhaust pressure valve is fixedly connected to the input end of the No. 1 exhaust temperature probe through a pipeline, the output end of the No. 1 exhaust temperature probe is fixedly connected to the input ends of the No. 1 air-cooled condenser and the No. 1 group 1 drying filter through pipelines, respectively, the output end of the No. 1 air-cooled condenser is fixedly connected to the input end of the No. 2 group 1 drying filter through a pipeline, the output end of the No. 2 group 1 drying filter is fixedly connected to the input end of the No. 1 low-temperature electronic expansion valve through a pipeline, and the output ends of the No. 1 low-temperature electronic expansion valve and the No. 1 group 1 normally closed solenoid valve are fixedly connected to the input end of the No. 1 check valve through pipelines.

[0039] The output end of the No. 1 group drier is fixedly connected to the input end of the No. 1 high-temperature electronic expansion valve through a pipeline, the output end of the No. 1 high-temperature electronic expansion valve is fixedly connected to the input ends of the No. 2 group 1 normally closed solenoid valve through pipelines, the output ends of the No. 2 group 1 normally closed solenoid valve and the No. 3 group 1 normally closed solenoid valve are fixedly connected to the input end of the No. 1 suction pressure valve through a pipeline, the output end of the No. 1 suction pressure valve is fixedly connected to the input end of the No. 1 suction temperature probe through a pipeline, and the output end of the No. 1 suction temperature probe is fixedly connected to the input end of the No. 1 compressor through a pipeline.

[0040] The output end of the No. 2 compressor is fixedly connected to the input end of the No. 2 exhaust pressure valve through a pipeline, the output end of the No. 2 exhaust pressure valve is fixedly connected to the input end of the No. 2 exhaust temperature probe through a pipeline, the output end of the No. 2 exhaust temperature probe is fixedly connected to the input ends of the No. 2 air-cooled condenser and the No. 1 two-group drying filter through pipelines respectively, the output end of the No. 1 air-cooled condenser is fixedly connected to the input end of the No. 2 two-group drying filter through a pipeline, the output end of the No. 2 two-group drying filter is fixedly connected to the input end of the No. 2 low-temperature electronic expansion valve through a pipeline, the output ends of the No. 2 low-temperature electronic expansion valve and the No. 1 two-group normally closed solenoid valve are fixedly connected to the input end of the No. 2 check valve through pipelines.

[0041] The output end of the No. 1 two-group drying filter is fixedly connected to the input end of the No. 2 high-temperature electronic expansion valve through a pipeline, the output end of the No. 2 high-temperature electronic expansion valve is fixedly connected to the input end of the No. 2 two-group normally closed solenoid valve through pipelines, the output ends of the No. 2 two-group normally closed solenoid valve and the No. 3 two-group normally closed solenoid valve are fixedly connected to the input end of the No. 2 suction pressure valve through a pipeline, the output end of the No. 2 suction pressure valve is fixedly connected to the input end of the No. 2 suction temperature probe through a pipeline, and the output end of the No. 2 suction temperature probe is fixedly connected to the input end of the No. 2 compressor through a pipeline.

[0042] The input end of the No. 3 battery pack inlet temperature probe is fixedly connected to the output end of the No. 2 one-way valve, the battery pack outlet temperature probe and the No. 1 one-way valve through a pipeline, and the output end of the battery pack outlet temperature probe is fixedly connected to the output end of the No. 3 group of normally closed battery solenoid valves through a pipeline.

[0043] The output end of the inlet battery pack temperature probe is fixedly connected to the input ends of battery pack No. 1, battery pack No. 2 and battery pack No. 3 through pipes, the output end of battery pack No. 1 is fixedly connected to the input end of battery solenoid valve No. 1 through a pipe, the output end of battery pack No. 2 is fixedly connected to the input end of battery solenoid valve No. 2 through a pipe, the output end of battery pack No. 3 is fixedly connected to the input end of battery solenoid valve No. 3 through a pipe, and the output ends of battery solenoid valve No. 1, battery solenoid valve No. 2 and battery solenoid valve No. 3 are fixedly connected to the input end of the outlet battery pack temperature probe through a pipe.

[0044] When in use, low-temperature refrigerant or high-temperature refrigerant directly enters the heat exchange plate of the battery pack to exchange heat with the battery cells in the battery pack. Heat exchange is no longer performed through other intermediate media, reducing heat loss.

[0045] A thermal management control method using direct cooling and heating of refrigerant, any one of the thermal management methods using direct cooling and heating of refrigerant, if the battery has cooling or heating requirements, the system determines whether there is a fault, when the system determines that there is a fault, the fault is reset, when the system determines that there is no fault, when the battery pack value N of the cooling requirement is greater than or equal to 12, system one and system two operate at the same time, when the battery pack value N of the cooling requirement is less than 12, the cumulative operating time of system one and system two is compared, and the system with the shorter cumulative operating time is started.

[0046] When the direct cooling control system is running, the heat pipe system determines whether there is a fault. When the heat pipe system determines that there is a fault, the fault is reset. When the heat pipe system has no fault, the outlet temperature is set to 18 degrees Celsius, and the number three group of normally closed solenoid valves are opened to start the heating management system. The compressor performs PID control according to the target temperature T: the low-temperature electronic expansion valve is controlled according to △T=0, and the dead zone is 0.5 for PID control. When the heat absorption: 1≤T﹤7 degrees Celsius and maintained for three minutes or T<one degree for thirty seconds, the high-temperature electronic expansion valve is opened, the number two group of normally closed solenoid valves are opened, and the suction superheat T=8, dead zone 1, is installed for PID control. When the heat absorption: 1≥T﹥7 degrees Celsius and maintained for three minutes or T>one degree for thirty seconds, the status quo is maintained.

[0047] When in use, when the battery pack has a cooling demand, when the battery pack has a cooling demand, it is determined whether to open one system or two systems according to the number of battery packs required. The refrigerant is compressed by the compressor to a high-temperature and high-pressure refrigerant gas that enters the air-cooled condenser for condensation, and becomes a normal temperature and high-pressure refrigerant liquid that passes through the filter and enters the low-temperature electronic expansion valve for throttling, and enters the heat exchange plate of the battery pack to exchange heat with the battery pack cells. If only the No. 1 heat pipe system 1 is opened at this time, the No. 1 high-temperature electronic expansion valve remains closed, and the No. 3 group of normally closed solenoid valves remains open. If only the No. 2 heat pipe system 2 is opened, the No. 2 high-temperature electronic expansion valve remains closed, and the No. 3 group of normally closed solenoid valves remains open. Taking the No. 1 heat pipe system 1 as an example, in order to ensure the uniformity of the temperature of each battery cell in the battery pack, the required inlet temperature of the battery pack is 18°C, and the outlet temperature of the battery pack also needs to meet 18°C. This requires that the refrigerant liquid entering the heat exchange plate is a gas-liquid two-phase refrigerant liquid after completing the latent heat exchange with the battery pack. In this way, the temperature of the inlet and outlet of the battery pack can be 18℃. Compressor No. 1 compares Tactual with TTarget and adjusts PID to ensure the supply of cooling capacity. Low-temperature electronic expansion valve No. 1 controls the opening change through the temperature difference between Tin and Tout △T=0, dead zone=0.5. Since the refrigerant out of the battery pack is in a gas-liquid two-phase state, it cannot be directly sucked into compressor No. 1, so it is necessary to open the normally closed solenoid valve No. 2 at this time, and use the high-temperature and high-pressure refrigerant gas at the exhaust end to throttle and reduce the pressure through the high-temperature electronic expansion valve No. 1 to become a high-temperature and normal-pressure refrigerant gas and mix it with the two-phase refrigerant out of the battery pack, and then become a refrigerant gas at normal temperature and pressure and enter the compressor. High-temperature electronic expansion valve No. 1 obtains the suction superheat through the suction temperature Tsuction-suction pressure corresponding to the saturation temperature Tsuction Saturation, and controls it to ensure that the state of the refrigerant sucked into compressor No. 1 is gas.

[0048] When the direct heating control system is started, the heat pipe system determines whether there is a fault. When the heat pipe system determines that there is a fault, the fault is reset. When the heat pipe system has no fault, the outlet temperature is set to 50 degrees, the number one group of normally closed solenoid valves and the number three group of normally closed solenoid valves are opened, the heating management system is turned on, the compressor is PID controlled according to the target temperature T, and the high-temperature electronic expansion valve is PID controlled according to the return air pressure of 1000kpa and the dead zone of 100kpa.

[0049] During use, when the battery pack has a heating demand, the thermal management system starts in heating mode. Taking the No. 1 heat pipe system 1 as an example, the No. 1 group of normally closed solenoid valves is opened, and the No. 1 low-temperature electronic expansion valve is closed. The high-temperature and high-pressure refrigerant gas at the outlet of the No. 1 compressor is throttled and reduced in pressure through the branch No. 1 high-temperature electronic expansion valve to become a high-temperature and normal-pressure refrigerant gas. The high-temperature and normal-pressure refrigerant gas enters the heat exchange plate and exchanges sensible heat with the battery pack to meet the heating needs of the battery. The No. 1 compressor compares the T actual and T target, and adjusts the PID to ensure the supply of heat. The No. 1 high-temperature electronic expansion valve throttles and reduces the pressure of the high-temperature and high-pressure refrigerant gas into a high-temperature and normal-pressure refrigerant gas, and controls the opening of the electronic expansion valve through the return gas pressure detection pressure value, and controls the return gas pressure at about 1000kpa.

[0050] It should be understood that the purpose of these embodiments is only to illustrate the present invention and is not intended to limit the protection scope of the present invention. In addition, it should also be understood that after reading the technical content of the present invention, those skilled in the art can make various changes, modifications and / or variations to the present invention, and all of these equivalent forms also fall within the protection scope defined by the appended claims of this application.

Claims

1. A dual thermal management system using refrigerant direct cooling and direct heating, comprising a first heat pipe system (1), a second heat pipe system (2) and a battery pack (3), characterized in that: The first heat pipe system (1) comprises a first compressor, a first exhaust pressure valve, a first temperature probe, a first battery pack inlet temperature probe, a first air-cooled condenser, a first filter drier, a first high-temperature electronic expansion valve, a first filter drier, a first group of normally closed solenoid valves, a second group of normally closed solenoid valves, a third group of normally closed solenoid valves and a first check valve, and the second heat pipe system (2) comprises a second compressor, a second exhaust pressure valve, a second temperature probe, a second battery pack inlet temperature probe, a second air-cooled condenser, a second filter drier, a second high-temperature electronic expansion valve, a second filter drier, a first group of normally closed solenoid valves, a second group of normally closed solenoid valves, a third group of normally closed solenoid valves and a second check valve; The battery pack (3) comprises a No. 3 battery pack inlet temperature probe, a battery pack outlet temperature probe, a No. 1 battery pack, a No. 2 battery pack, a No. 3 battery pack, a No. 1 battery solenoid valve, a No. 2 battery solenoid valve and a No. 3 battery solenoid valve.

2. According to claim 1, a thermal management dual system using refrigerant direct cooling and direct heating is characterized in that: The output end of the No. 1 compressor is fixedly connected to the input end of the No. 1 exhaust pressure valve through a pipeline, the output end of the No. 1 exhaust pressure valve is fixedly connected to the input end of the No. 1 exhaust temperature probe through a pipeline, the output end of the No. 1 exhaust temperature probe is fixedly connected to the input ends of the No. 1 air-cooled condenser and the No. 1 group of drying filters through pipelines, respectively, the output end of the No. 1 air-cooled condenser is fixedly connected to the input end of the No. 2 group of drying filters through a pipeline, the output end of the No. 2 group of drying filters is fixedly connected to the input end of the No. 1 low-temperature electronic expansion valve through a pipeline, and the output ends of the No. 1 low-temperature electronic expansion valve and the No. 1 group of normally closed solenoid valves are fixedly connected to the input end of the No. 1 check valve through pipelines.

3. According to claim 1, a thermal management dual system using refrigerant direct cooling and direct heating is characterized in that: The output end of the No. 1 group of drying filters is fixedly connected to the input end of the No. 1 high-temperature electronic expansion valve through a pipeline, the output end of the No. 1 high-temperature electronic expansion valve is fixedly connected to the input ends of the No. 2 group of normally closed solenoid valves through pipelines, the output ends of the No. 2 group of normally closed solenoid valves and the No. 3 group of normally closed solenoid valves are fixedly connected to the input end of the No. 1 suction pressure valve through a pipeline, the output end of the No. 1 suction pressure valve is fixedly connected to the input end of the No. 1 suction temperature probe through a pipeline, and the output end of the No. 1 suction temperature probe is fixedly connected to the input end of the No. 1 compressor through a pipeline.

4. The thermal management dual system using direct cooling and direct heating of refrigerants according to claim 1, characterized in that: The output end of the No. 2 compressor is fixedly connected to the input end of the No. 2 exhaust pressure valve through a pipeline, the output end of the No. 2 exhaust pressure valve is fixedly connected to the input end of the No. 2 exhaust temperature probe through a pipeline, the output end of the No. 2 exhaust temperature probe is fixedly connected to the input ends of the No. 2 air-cooled condenser and the No. 1 two-group drying filter through pipelines, respectively, the output end of the No. 1 air-cooled condenser is fixedly connected to the input end of the No. 2 two-group drying filter through a pipeline, the output end of the No. 2 two-group drying filter is fixedly connected to the input end of the No. 2 low-temperature electronic expansion valve through a pipeline, and the output ends of the No. 2 low-temperature electronic expansion valve and the No. 1 two-group normally closed solenoid valve are fixedly connected to the input end of the No. 2 check valve through pipelines.

5. The thermal management dual system using direct cooling and direct heating of refrigerants according to claim 1, characterized in that: The output end of the No. 1 two-group drying filter is fixedly connected to the input end of the No. 2 high-temperature electronic expansion valve through a pipeline, the output end of the No. 2 high-temperature electronic expansion valve is fixedly connected to the input end of the No. 2 two-group normally closed solenoid valve through pipelines, the output ends of the No. 2 two-group normally closed solenoid valve and the No. 3 two-group normally closed solenoid valve are fixedly connected to the input end of the No. 2 suction pressure valve through a pipeline, the output end of the No. 2 suction pressure valve is fixedly connected to the input end of the No. 2 suction temperature probe through a pipeline, and the output end of the No. 2 suction temperature probe is fixedly connected to the input end of the No. 2 compressor through a pipeline.

6. The thermal management dual system using direct cooling and direct heating of refrigerants according to claim 1, characterized in that: The input end of the No. 3 battery pack inlet temperature probe is fixedly connected to the output ends of the No. 2 one-way valve, the battery pack outlet temperature probe and the No. 1 one-way valve through a pipeline, and the output end of the battery pack outlet temperature probe is fixedly connected to the output end of the No. 3 group of normally closed battery solenoid valves through a pipeline.

7. The thermal management dual system using direct cooling and direct heating of refrigerants according to claim 1, characterized in that: The output end of the inlet battery pack temperature probe is fixedly connected to the input ends of battery pack No. 1, battery pack No. 2 and battery pack No. 3 through a pipeline; the output end of battery pack No. 1 is fixedly connected to the input end of battery solenoid valve No. 1 through a pipeline; the output end of battery pack No. 2 is fixedly connected to the input end of battery solenoid valve No. 2 through a pipeline; the output end of battery pack No. 3 is fixedly connected to the input end of battery solenoid valve No. 3 through a pipeline; the output ends of battery solenoid valve No. 1, battery solenoid valve No. 2 and battery solenoid valve No. 3 are fixedly connected to the input end of the outlet battery pack temperature probe through a pipeline.

8. A thermal management control method using direct cooling and direct heating of a refrigerant, the method using a thermal management method using direct cooling and direct heating of a refrigerant as claimed in any one of claims 1 to 8, characterized in that: If the battery has cooling or heating requirements, the system determines whether there is a fault. When the system determines that there is a fault, the fault is reset. When the system determines that there is no fault, when the battery pack value N of the cooling requirement is greater than or equal to 12, system one and system two operate simultaneously. When the battery pack value N of the cooling requirement is less than 12, the cumulative operating time of system one and system two is compared, and the system with the shorter cumulative operating time is started.

9. The method according to claim 8, characterized in that: When the direct cooling control system is running, the heat pipe system determines whether there is a fault. When the heat pipe system determines that there is a fault, the fault is reset. When the heat pipe system has no fault, the outlet temperature is set to 18 degrees Celsius, and the normally closed solenoid valve No. 3 group is opened to start the heating management system. The compressor is PID controlled according to the target temperature T: the low-temperature electronic expansion valve is controlled according to △T=0, and the dead zone is 0.5 for PID control. When the heat absorption: 1≤T﹤7 degrees Celsius and maintained for three minutes or T<1 degree for thirty seconds, the high-temperature electronic expansion valve is opened, the normally closed solenoid valve No. 2 group is opened, and the suction superheat T=8 is installed, the dead zone 1, and PID control is performed. When the heat absorption: 1≥T﹥7 degrees Celsius and maintained for three minutes or T>1 degree for thirty seconds, the status quo is maintained.

10. The method according to claim 8, characterized in that: When the direct heating control system is started, the heat pipe system determines whether there is a fault. When the heat pipe system determines that there is a fault, the fault is reset. When the heat pipe system has no fault, the liquid outlet temperature is set to 50 degrees, the number one group of normally closed solenoid valves and the number three group of normally closed solenoid valves are opened, and the heating management system is turned on. The compressor is PID controlled according to the target temperature T, and the high-temperature electronic expansion valve is PID controlled according to the return air pressure of 1000kpa and the dead zone of 100kpa.

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