Electric vehicle heat pump type heat storage system and control method

Abstract

The application relates to an electric vehicle heat pump type heat storage system and a control method, and relates to the technical field of new energy vehicle heat energy management. The system comprises an energy storage module, a front end heat exchanger of which is connected to an electric vehicle heat pump system through a heat storage pipeline, the state of the energy storage module comprises a heat storage mode, a heat release mode and a static mode; a control module is used for judging the state of the energy storage module and sending a control signal; and an execution module is used for responding to the control signal and switching the state of the energy storage module. The application has the effects of making the transportation and storage of heat more free and improving the energy consumption performance of the whole vehicle.

Description

Technical Field

[0001] This invention relates to the field of thermal energy management technology for new energy vehicles, and in particular to a heat pump thermal storage system and control method for electric vehicles. Background Technology

[0002] In electric vehicles, the driving range decreases significantly in winter. This is partly due to the electrical energy used for passenger cabin heating to ensure passenger comfort. Traditional electric vehicles use PCT (Preheating Circuit) heating, which consumes a large amount of electrical energy, further reducing the driving range of electric vehicles.

[0003] Currently, some car models on the market use heat pump systems. A typical heat pump system achieves energy savings by transferring heat.

[0004] The greatest heat demand for electric vehicles in winter occurs during cold starts, when heat is needed to warm the passenger compartment. The period when the vehicle's systems generate the most heat in winter is during fast charging, due to the heat from the battery. Since starting and charging do not occur simultaneously, this results in wasted heat. Summary of the Invention

[0005] To enable more flexible heat transport and storage and improve the overall energy efficiency of the vehicle, this invention provides a heat pump-type heat storage system and control method for electric vehicles.

[0006] In a first aspect, the present invention provides a heat pump-type thermal storage system for electric vehicles, which adopts the following technical solution:

[0007] A heat pump-type thermal storage system for electric vehicles, comprising:

[0008] An energy storage module is connected in parallel to the front-end heat exchanger of the electric vehicle heat pump system via a heat storage pipeline. The energy storage module has three states: heat storage mode, heat release mode, and static mode.

[0009] A control module, connected to the energy storage module, is used to determine the state of the energy storage module and respond to control signals.

[0010] And an execution module that responds to the control signal and switches the state of the energy storage module.

[0011] Furthermore, in the aforementioned electric vehicle heat pump thermal storage system, the energy storage module includes:

[0012] An energy storage device is connected in series on the heat storage pipeline for heat exchange with the medium in the heat storage pipeline.

[0013] A power unit is connected in series on the heat storage pipeline to provide power to the medium in the heat storage pipeline.

[0014] Furthermore, in the aforementioned electric vehicle heat pump thermal storage system, the energy storage module includes:

[0015] A heat exchange device is connected in parallel on the heat storage pipeline;

[0016] The heat-conducting pipes exchange heat with the heat storage pipes in the heat exchange device;

[0017] An energy storage device is connected in series on the heat-conducting pipe for heat exchange with the medium in the heat-conducting pipe.

[0018] A power unit is connected in series on the heat-conducting pipe to provide power to the medium inside the heat-conducting pipe.

[0019] Furthermore, in the aforementioned electric vehicle heat pump thermal storage system, the execution module includes a thermal storage shut-off valve and a front-end shut-off valve. The thermal storage shut-off valve is connected in series on the thermal storage pipeline, and the front-end shut-off valve is connected in series with the front-end heat exchanger.

[0020] Furthermore, in the aforementioned electric vehicle heat pump thermal storage system, the system further includes:

[0021] The detection module is used to detect the percentage of energy stored in the energy storage module.

[0022] Furthermore, in the aforementioned electric vehicle heat pump thermal storage system, the detection module includes:

[0023] A temperature detection unit is installed in the heat-conducting pipe to detect the temperature of the medium in the heat-conducting pipe.

[0024] Secondly, this invention provides a heat pump-type thermal storage control method for electric vehicles, employing the following technical solution:

[0025] A method for controlling heat pump-type thermal storage in electric vehicles includes:

[0026] Obtain the status information of the vehicle's heat pump system;

[0027] Based on the status information of the heat pump system, determine the status of the energy storage module;

[0028] And the state control execution module based on the energy storage module responds;

[0029] The energy storage module's states include thermal storage mode, thermal release mode, and static mode.

[0030] Furthermore, the above-mentioned method for controlling heat pump-type thermal storage in electric vehicles also includes:

[0031] The energy storage percentage of the energy storage module is updated based on the state of the thermal storage mode.

[0032] Furthermore, in the above-mentioned electric vehicle heat pump-type thermal storage control method, the energy storage percentage of the energy storage module updated based on the thermal storage mode includes:

[0033] When the energy storage module is in thermal storage mode, the rotational speed of the power unit is acquired, and the medium flow rate is calculated; the medium temperature values ​​at the inlet and outlet of the heat conduction pipe are acquired; the instantaneous thermal storage power is calculated based on the medium temperature values ​​at the inlet and outlet and the medium flow rate; the energy storage percentage is generated based on the instantaneous thermal storage power and the total thermal storage capacity of the energy storage module; and / or, when the energy storage module is in heating mode, the rotational speed of the power unit is acquired, and the medium flow rate is calculated; the medium temperature values ​​at the inlet and outlet of the heat conduction pipe are acquired; the instantaneous heating power is calculated based on the medium temperature values ​​at the inlet and outlet and the medium flow rate; the energy storage percentage is generated based on the instantaneous heating power and the total thermal storage capacity of the energy storage module; and / or, when the energy storage module is in static mode, the instantaneous heat dissipation power is obtained by looking up a table according to the ambient temperature; the energy storage percentage is generated based on the instantaneous heat dissipation power and the total thermal storage capacity of the energy storage module.

[0034] Furthermore, in the above-mentioned electric vehicle heat pump thermal storage control method, the status information of the heat pump system includes the shape of the front-end heat exchanger in the heat pump system, and the shape of the front-end heat exchanger includes the condenser shape in the cooling mode and the evaporator shape in the heating mode.

[0035] Furthermore, in the above-mentioned electric vehicle heat pump thermal storage control method, the status information of the heat pump system also includes the medium pressure in the heat pump system pipeline.

[0036] Furthermore, in the above-mentioned electric vehicle heat pump thermal storage control method, the status information of the heat pump system also includes the temperature of the medium in the heat pump system pipeline.

[0037] Furthermore, in the above-mentioned electric vehicle heat pump-type thermal storage control method, determining the state of the energy storage module based on the state information of the heat pump system includes:

[0038] When the front-end heat exchanger is in condenser form, the medium pressure is greater than a preset first pressure value, or the medium temperature is greater than a preset first temperature value, and the energy storage percentage is not 100%, the energy storage module is in thermal storage mode; and / or,

[0039] When the front-end heat exchanger is in evaporator form, the medium pressure is less than a preset second pressure value, or the medium temperature is less than a preset second temperature value, and the energy storage percentage is not 0%, the energy storage module is in heat release mode; and / or,

[0040] When the medium pressure is between the first pressure value and the second pressure value, and the medium temperature is between the first temperature value and the second temperature value, the energy storage module is in static mode.

[0041] Furthermore, in the above-mentioned electric vehicle heat pump thermal storage control method, the response of the state control execution module based on the energy storage module includes:

[0042] When the energy storage module is in thermal storage mode, the thermal storage shut-off valve is opened and the front-end shut-off valve is closed; the power unit is controlled according to the system high pressure table, and the higher the medium pressure, the greater the speed of the power unit; when the speed of the power unit reaches its maximum value and the medium pressure is still rising, the front-end shut-off valve is opened; and / or,

[0043] When the heat storage mode is in the heat release mode, the heat storage shut-off valve is opened and the front-end shut-off valve is closed; the power unit is controlled according to the system low-pressure lookup table, and the higher the medium pressure, the greater the speed of the power unit; when the power unit speed reaches its maximum value and the medium pressure is still decreasing, the front-end shut-off valve is opened; and / or,

[0044] When the heat storage mode is in static mode, the heat storage shut-off valve is closed, the front-end shut-off valve is opened, and the power unit is turned off.

[0045] In summary, the present invention has at least one of the following beneficial technical effects:

[0046] The greatest heat demand from air conditioning in winter occurs during cold starts, while fast charging requires battery cooling, resulting in heat waste. This invention adds a heat pump thermal storage function to the existing heat pump system, achieving not only spatial but also temporal heat transfer. This invention provides a heat pump thermal storage system for electric vehicles and its control. By expanding the hardware and developing intelligent algorithms within the existing heat pump system, the system's thermal storage capability is achieved. This allows for more flexible energy transfer and storage, thereby improving the overall energy efficiency of the vehicle. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the heating cycle in a heat pump system in the prior art.

[0048] Figure 2 This is a schematic diagram of the refrigeration cycle in a heat pump system in the prior art.

[0049] Figure 3 This is a schematic diagram of the structure of an embodiment of the electric vehicle heat pump thermal storage system of the present invention.

[0050] Figure 4 This is a flowchart of one embodiment of the electric vehicle heat pump thermal storage control method of the present invention.

[0051] Figure 5 This is a flowchart of another embodiment of the electric vehicle heat pump thermal storage control method of the present invention.

[0052] Figure 6 This is a flowchart of another embodiment of the electric vehicle heat pump thermal storage control method of the present invention.

[0053] Explanation of reference numerals in the attached diagram: 1. Compressor; 2. User side; 3. Front-end heat exchanger; 4. Four-way valve; 6. Throttling valve; 7. Energy storage module; 71. Heat exchange device; 72. Heat transfer pipeline; 73. Energy storage device; 74. Power unit; 8. Heat storage pipeline; 9. Actuation module; 91. Heat storage shut-off valve; 92. Front-end shut-off valve. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, 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.

[0055] The method steps described in this embodiment of the invention can be executed in the order described in the specific implementation, or the execution order of each step can be adjusted according to actual needs, provided that the technical problem can be solved. These are not listed one by one here.

[0056] The principle of an electric vehicle heat pump system is to utilize a thermal cycle to transfer a low-temperature heat source, such as circulating water or outdoor air, to a high-temperature object for heating the passenger cabin. To transfer energy from the low-temperature heat source to the high-temperature heat source, the heat pump system requires external driving energy, which can be electrical or mechanical. The higher the flow rate and temperature, the greater the driving energy requirement. However, special valves in the refrigeration piping of the heat pump system allow for reverse circulation, enabling the system to perform both heating and cooling.

[0057] Reference Figure 1 and Figure 2 Common heat pump systems include a compressor 1 for providing driving energy, a user side 2 for cooling or heating the passenger cabin, a front heat exchanger 3 for front-end heat exchange, a four-way valve 4 for controlling the circulation direction, and a throttle valve 6, among other supporting devices.

[0058] Reference Figure 1During the heating cycle, the medium inside the pipe is compressed into a high-temperature medium by the compressor 1. The high-temperature medium flows through the four-way valve 4 to the use side 2 located in the passenger compartment, providing heat energy to the passenger compartment before flowing to the front heat exchanger 3. At this time, the front heat exchanger 3 is used as an evaporator in the heat pump system.

[0059] Reference Figure 2 During the refrigeration cycle, the energy of the medium in the user-side pipe 2 located in the passenger compartment is extracted by the compressor 1, thereby reducing the temperature of the medium in the user-side pipe 2 and achieving the purpose of lowering the temperature of the passenger compartment. The medium in the pipe that has been heated by the compressor 1 flows through the four-way valve 4 to the front heat exchanger 3 for cooling, and then flows back to the user-side 2 for further cooling. At this time, the front heat exchanger 3 is used as a condenser in the heat pump system.

[0060] Based on the above-mentioned cooling / heating principle of heat pump systems, this invention provides a heat pump thermal storage system for electric vehicles.

[0061] Reference Figure 3 A heat pump-type thermal storage system for electric vehicles, comprising:

[0062] The energy storage module 7 is connected in parallel to the front-end heat exchanger 3 of the electric vehicle heat pump system via the heat storage pipeline 8. The states of the energy storage module 7 include heat storage mode, heat release mode and static mode.

[0063] A control module, connected to the energy storage module 7, is used to determine the state of the energy storage module 7 and respond to control signals; and an execution module 9, which responds to and switches the state of the energy storage module 7 based on the control signals.

[0064] When the vehicle battery is fast-charging, the traditional front-end heat exchanger 3 is used as a condenser to dissipate heat from the battery in a timely manner. However, based on the heat storage system of this invention, the energy storage module 7 is used in parallel with the front-end heat exchanger 3, and the energy storage module 7 replaces the front-end heat exchanger 3 as a condenser. The control module sets the state of the energy storage module 7 to heat storage mode, and the execution module 9 responds to the action in heat storage mode, thereby storing the heat generated by the battery fast charging in the energy storage module 7.

[0065] When the passenger cabin needs to be heated, the energy storage module 7 can replace the front heat exchanger 3 as an evaporator. The control module sets the state of the energy storage module 7 to heat release mode, and the execution module 9 responds to the action in heat release mode, thereby improving the heating coefficient and preventing frost formation.

[0066] Furthermore, as a specific embodiment of the present invention, refer to... Figure 3 The energy storage module 7 includes a heat exchange device 71, a heat conduction pipeline 72, an energy storage device 73, and a power device 74.

[0067] The heat exchange device 71 is connected in parallel on the heat storage pipeline 8. In this embodiment, the heat exchange device 71 can be a plate heat exchanger.

[0068] The heat-conducting pipe 72 and the heat storage pipe 8 exchange heat in the heat exchange device 71.

[0069] The energy storage device 73 can be a phase change material, serving as a cold and heat storage device. The energy storage device 73 is connected in series on the heat-conducting pipe 72 for heat exchange with the medium within the heat-conducting pipe 72.

[0070] In this embodiment, the power unit 74 can be a hot water storage pump, which is connected in series on the heat conduction pipe 72 to provide power to the medium in the heat conduction pipe 72.

[0071] Specifically, when the medium in the front-end heat exchanger 3 of the heat pump system is refrigerant, that is, when refrigerant flows in the heat storage pipeline 8, the refrigerant in the heat storage pipeline 8 and the heat conduction pipeline 72 transfer heat through the plate heat exchanger.

[0072] When the energy storage device 73 is in thermal storage mode, the refrigerant is at a high temperature. The refrigerant flows through the plate heat exchanger in the thermal storage pipeline 8, exchanging heat with the medium in the heat transfer pipeline 72. The medium in the heat transfer pipeline 72 can be water. After the coolant is heated in the plate heat exchanger, it is transferred to the energy storage device 73 by the action of the hot water pump. In the energy storage device 73, the heat of the coolant is converted into storable energy and stored.

[0073] When the energy storage device 73 is in heat release mode, the energy storage device 73 releases heat to increase the temperature of the coolant in the heat conduction pipe 72. The high-temperature coolant exchanges heat in the plate heat exchanger to increase the temperature of the refrigerant in the heat storage pipe 8, thereby facilitating the heating of the passenger compartment, improving heating efficiency, and thus increasing the driving range of the electric vehicle in winter.

[0074] Furthermore, as one embodiment of the present invention, refer to Figure 3 The execution module 9 includes a heat storage shut-off valve 91 and a front-end shut-off valve 92. The heat storage shut-off valve 91 is connected in series on the heat storage pipeline 8, and the front-end shut-off valve 92 is connected in series with the front-end heat exchanger 3.

[0075] Specifically, when the control mode determines that the energy storage module 7 is in heat storage mode or heat release mode, the heat storage shut-off valve 91 opens and the front shut-off valve 92 closes, so that the medium in the heat storage pipeline 8 exchanges heat with the energy storage module 7, thereby effectively storing the excess heat in the heat pump system and using the energy stored in the heat storage module 7 to improve the heating efficiency of the heat pump system.

[0076] When the heat pump system of the control module is in normal mode, the heat storage shut-off valve 91 is closed and the front-end shut-off valve 92 is open, allowing the medium in the heat storage pipeline 8 to flow normally to the front-end heat exchanger 3. At this time, the energy storage module 7 is in static mode, that is, it neither stores energy nor releases heat.

[0077] Furthermore, as a specific embodiment of the present invention, the system of the present invention further includes: a detection module, which is used to detect the energy percentage of the energy stored in the energy storage module 7.

[0078] Specifically, in one embodiment of the present invention, the detection module includes a temperature detection unit and a flow rate detection unit. The temperature detection unit is disposed in the heat storage pipeline 8 and is used to detect the temperature of the medium in the heat storage pipeline 8.

[0079] When energy storage module 7 is in thermal storage mode, the detection module will calculate the percentage of energy stored in energy storage module 7. The calculation process is as follows:

[0080] The water flow rate in energy storage module 7 is obtained by referring to a table based on the average water temperature and the speed of the hot water pump. The water temperature values ​​at the inlet and outlet of energy storage module 7 are read. The instantaneous energy storage power is calculated using the water flow rate and the difference between the inlet and outlet temperatures of energy storage module 7. The instantaneous energy storage percentage is obtained by dividing the instantaneous energy storage power by the total energy storage capacity, and the accumulated percentages are the total stored energy.

[0081] When energy storage module 7 is in heat dissipation mode, the detection module will calculate the percentage of energy released by energy storage module 7. The calculation process is as follows:

[0082] The water flow rate in energy storage module 7 is obtained by referring to a table based on the average water temperature and the speed of the hot water pump. The water temperature values ​​at the inlet and outlet of the energy storage system are read. The instantaneous energy storage power is calculated using the water flow rate and the difference between the inlet and outlet temperatures of energy storage module 7. The instantaneous energy storage percentage is obtained by dividing the instantaneous energy storage power by the total thermal storage capacity, and the remaining energy storage percentage is obtained by subtracting these values.

[0083] The implementation principle of an embodiment of the electric vehicle heat pump thermal storage system of the present invention is as follows: when using the electric vehicle heat pump system, especially when using the electric vehicle heat pump system to transfer and transport heat inside the vehicle in winter, the energy storage module 7 in this system can replace the front-end heat exchanger 3 in the heat pump system.

[0084] When fast charging an electric vehicle battery in winter, the heat pump system operates in cooling mode to dissipate heat from the battery, and this heat is transferred to the heat storage pipe 8. In traditional heat pump systems, after the heat is transferred to the heat storage pipe 8, it is transported to the front-end heat exchanger 3 for cooling. At this time, the front-end heat exchanger 3 is used as a condenser to cool the medium in the heat storage pipe 8, but this also results in heat loss and waste. Under the control of the control module, this system can close the front-end shut-off valve 92 at the front-end heat exchanger 3 and open the heat storage shut-off valve 91, allowing the high-temperature medium in the heat storage pipe 8 to exchange heat with the energy storage module 7. The energy storage module 7 then replaces the front-end heat exchanger 3 as a condenser, and the heat in the high-temperature medium is converted into storable energy in the energy storage module 7. This achieves effective storage of the energy generated by heat sources (such as the battery during fast charging) in the vehicle while dissipating heat, thus improving the energy utilization rate in the vehicle.

[0085] When heating the passenger compartment of an electric vehicle in winter, the heat pump system operates in heating mode. Heat needs to be transferred to the user side 2 of the passenger compartment by the action of the compressor pump. In traditional heat pump systems, the front-end heat exchanger 3 needs to be used as an evaporator under the action of the compressor pump. However, since the front-end heat exchanger 3 is at a low temperature, if it can function as an evaporator, the compressor pump needs to provide a large pressure to evacuate the medium at the front-end heat exchanger 3 to a low-pressure state, which requires the compressor pump to consume a lot of mechanical energy. In contrast, when heating the passenger compartment, this system can open the heat storage shut-off valve 91 and close the front-end shut-off valve 92, using the energy storage module 7 instead of the front-end heat exchanger 3 as an evaporator. While the compressor pump creates a vacuum to form a low pressure, the energy storage module 7 also releases heat to increase the temperature of the medium inside the pipe. Therefore, compared with the compressor pump of the traditional heat pump system, less mechanical energy is consumed, thereby improving the heating coefficient and saving energy while heating the passenger compartment and preventing frost.

[0086] Based on the above-mentioned electric vehicle heat pump thermal storage system, this invention also discloses an electric vehicle heat pump thermal storage control method.

[0087] Reference Figure 4 A method for controlling heat pump-type thermal storage in electric vehicles, comprising:

[0088] S1, obtain the status information of the vehicle's heat pump system;

[0089] S2, based on the status information of the heat pump system, determine the status of the energy storage module 7;

[0090] S3, the energy storage module 7 is controlled by the execution module 9, which then responds.

[0091] The energy storage module 7 has three states: heat storage mode, heat release mode, and static mode.

[0092] This invention obtains the status information of the electric vehicle heat pump system, judges the status of the energy storage module 7 based on the status information, and controls the execution module 9 to take action based on the judgment result, thereby achieving the purpose of storing excess heat when the heat pump system is in cooling mode and improving heating efficiency when the heat pump system is in heating mode.

[0093] Furthermore, as one embodiment of the present invention, refer to Figure 5 A heat pump-type thermal storage control method for electric vehicles also includes:

[0094] S4, update the energy storage percentage of energy storage module 7 based on the thermal storage mode. By adopting the technical solution in step S4, the energy storage percentage of energy storage module 7 can be updated in real time.

[0095] Furthermore, as a specific embodiment of the present invention, step S4 includes:

[0096] Firstly, when the energy storage module 7 is in thermal storage mode, the flow rate of the medium in the heat transfer pipe 72 and the temperature values ​​of the medium at the inlet and outlet are obtained; the instantaneous energy storage power is calculated based on the medium temperature values ​​at the inlet and outlet and the medium flow rate; and the energy storage percentage is generated based on the instantaneous energy storage power and the total energy storage capacity of the energy storage module 7. Specifically, in this embodiment, the flow rate of the medium in the heat transfer pipe 72 at this time is obtained by looking up a table according to the average water temperature of the thermal storage and the speed of the hot water pump. The instantaneous energy storage power is calculated by the difference between the medium flow rate and the medium temperature at the inlet and outlet. The instantaneous energy storage percentage is obtained by dividing the instantaneous energy storage power by the total energy storage capacity, and the cumulative percentage is obtained.

[0097] Secondly, when the energy storage module 7 is in heating mode, the flow rate of the medium in the heat-conducting pipe 72 and the temperature values ​​of the medium at the inlet and outlet are obtained; the instantaneous heating power is calculated based on the medium temperature values ​​at the inlet and outlet and the medium flow rate; and the energy storage percentage is generated based on the instantaneous heating power and the total heat storage capacity of the energy storage module 7. Specifically, in this embodiment, the water flow rate in the heat-conducting pipe 72 at this time is obtained by looking up a table according to the average water temperature of the heat storage and the speed of the hot water pump. The instantaneous heating power is calculated by the difference between the medium flow rate and the medium temperature at the inlet and outlet. The instantaneous heating percentage is obtained by dividing the instantaneous heating power by the total heat storage capacity, and the remaining energy storage percentage is obtained by subtracting from the calculated value.

[0098] Third, when the energy storage module 7 is in static mode, the instantaneous heat dissipation power is obtained by looking up a table based on the ambient temperature; the energy storage percentage is generated based on the instantaneous heat dissipation power and the total heat storage capacity of the energy storage module 7. Specifically, in this embodiment, the instantaneous heat dissipation power is obtained by looking up a table based on the ambient temperature, the instantaneous heat dissipation power / total heat storage capacity gives the instantaneous heat dissipation percentage, and the remaining energy storage percentage is obtained by subtracting from the instantaneous heat dissipation power.

[0099] Furthermore, as a specific embodiment of the present invention, the status information of the heat pump system includes the shape of the front-end heat exchanger 3 in the heat pump system, and the shape of the front-end heat exchanger 3 includes the condenser shape in the cooling mode and the evaporator shape in the heating mode.

[0100] Furthermore, as a specific embodiment of the present invention, the status information of the heat pump system also includes the medium pressure in the heat pump system pipeline.

[0101] Furthermore, as a specific embodiment of the present invention, the status information of the heat pump system also includes the temperature of the medium in the heat pump system pipeline.

[0102] Based on the above embodiments, one specific implementation of step S2 includes:

[0103] Firstly, when the front-end heat exchanger 3 is in condenser mode, the medium pressure is greater than a preset first pressure value, or the medium temperature is greater than a preset first temperature value, and the energy storage percentage is not 100%, the energy storage module 7 is in heat storage mode, and the energy storage device 73 begins energy storage. Specifically, when the front-end heat exchanger 3 is in condenser mode, it indicates that the heat pump system is in cooling mode. When the upstream medium pressure of the front-end heat exchanger 3 of the heat pump system is greater than a certain rated value, or the upstream medium temperature is greater than a certain rated value, it indicates that there is excess energy in the heat pump system, and excess heat needs to be stored. The above two situations refer to the situation where the heat pump system is in cooling mode and generates excess heat. If the energy storage percentage in the energy storage device 73 is not 100%, the excess heat is transferred to the energy storage device 73 and converted into storable energy for storage.

[0104] Secondly, when the front-end heat exchanger 3 is in evaporator mode, the medium pressure is less than a preset second pressure value, or the medium temperature is less than a preset second temperature value, and the energy storage percentage is not 0%, the energy storage module 7 is in heat release mode, and the energy storage device 73 begins to release heat. Specifically, when the front-end heat exchanger 3 is in evaporator mode, it indicates that the heat pump system is in heating mode. When the upstream medium pressure of the front-end heat exchanger 3 is less than a certain calibrated value, or the upstream medium temperature is less than a certain calibrated value, it indicates that the heat pump system lacks energy and needs some energy replenishment. The above two situations refer to the situation where the heat pump system is in heating mode and there is an energy shortage. If the energy storage percentage in the energy storage device 73 is not 0%, the energy storage device 73 is used to replenish the energy of the heat pump system.

[0105] Third, when the above conditions are not met, that is, when the medium pressure is between the first pressure value and the second pressure value and the medium temperature is between the first temperature value and the second temperature value, the energy storage module 7 is in a static mode, that is, the energy storage device 73 does not store energy or release heat.

[0106] Furthermore, as a specific embodiment of the present invention, step S3 includes:

[0107] Firstly, when the energy storage module 7 is in the heat storage mode, the heat storage shut-off valve 91 is opened and the front shut-off valve 92 is closed; the power unit 74 is controlled according to the system high pressure table. The higher the medium pressure, the greater the speed of the power unit 74; when the speed of the power unit 74 reaches the maximum value and the medium pressure is still rising, the front shut-off valve 92 is opened, so that the front heat exchanger 3 and the energy storage device 73 are used as condensers in the heat pump system at the same time;

[0108] Secondly, when the heat storage mode is in the heat release mode, the heat storage shut-off valve 91 is opened and the front shut-off valve 92 is closed; the power unit 74 is controlled according to the low pressure of the system. The higher the medium pressure, the greater the speed of the power unit 74; when the speed of the power unit 74 reaches the maximum value and the medium pressure is still decreasing, the front shut-off valve 92 is opened, so that the front heat exchanger 3 and the energy storage device 73 are used as evaporators in the heat pump system at the same time;

[0109] Third, when the heat storage mode is in static mode, the heat storage shut-off valve 91 is closed, the front-end shut-off valve 92 is opened, and the power unit 74 is turned off. At this time, the heat storage system stops working, and the heat pump system works independently.

[0110] The implementation principle of one embodiment of the electric vehicle heat pump thermal storage control method of the present invention is as follows: (Refer to...) Figure 6 After the heat pump system starts working, the state of the energy storage module 7 is determined based on the energy storage percentage in the energy storage device 73 and the state information of the heat pump system. When the energy storage module 7 is in heat storage mode, the control execution module 9 executes the heat storage mode response; when the energy storage module 7 is in heat release mode, the control execution module 9 executes the heat release mode response; when the energy storage module 7 is in static mode, the control execution module 9 executes the static mode response. Simultaneously, the state of the energy storage module 7 is continuously assessed after each response to control the heat storage system in real time.

[0111] The control method of this invention is independent of the control module of a conventional heat pump system, achieving decoupling from the control of a conventional heat pump system, thus making this invention an additional configuration option for a traditional heat pump system.

[0112] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A heat pump-type thermal storage system for electric vehicles, characterized in that, include: The energy storage module (7) is connected in parallel to the front-end heat exchanger (3) of the electric vehicle heat pump system through the heat storage pipeline (8). The states of the energy storage module (7) include heat storage mode, heat release mode and static mode. The detection module is used to detect the percentage of energy stored in the energy storage module (7); The control module is used to acquire the status information of the vehicle heat pump system, determine the status of the energy storage module (7) based on the status information and the energy storage percentage, and issue a control signal. as well as The execution module (9) responds to the control signal and switches the state of the energy storage module (7); The energy storage module (7) includes a heat exchange device (71), a heat conduction pipeline (72), an energy storage device (73), and a power device (74). The heat exchange device (71) is installed on the heat storage pipeline (8). The heat conduction pipeline (72) and the heat storage pipeline (8) exchange heat in the heat exchange device (71). The energy storage device (73) is connected in series on the heat conduction pipeline (72) for heat conversion with the medium in the heat conduction pipeline (72). The power device (74) is connected in series on the heat conduction pipeline (72) for providing power to the medium in the heat conduction pipeline (72). The execution module (9) includes a heat storage shut-off valve (91) and a front-end shut-off valve (92). The heat storage shut-off valve (91) is connected in series on the heat storage pipeline (8), and the front-end shut-off valve (92) is connected in series with the front-end heat exchanger (3). The status information of the vehicle heat pump system includes the shape of the front heat exchanger (3) and the medium pressure and medium temperature in the pipeline of the vehicle heat pump system. The shape of the front heat exchanger (3) includes the condenser shape in the cooling mode and the evaporator shape in the heating mode. The control module is specifically used to: determine that the energy storage module (7) is in heat storage mode when the front-end heat exchanger (3) is in condenser mode, the energy storage percentage is not 100%, and at least one of the following conditions is met: the medium pressure is greater than a preset first pressure value and the medium temperature is greater than a preset first temperature value; and determine that the energy storage module (7) is in heat release mode when the front-end heat exchanger (3) is in evaporator mode, the energy storage percentage is not 0%, and at least one of the following conditions is met: the medium pressure is less than a preset second pressure value and the medium temperature is less than a preset second temperature value. When the medium pressure is between the first pressure value and the second pressure value and the medium temperature is between the first temperature value and the second temperature value, it is determined that the energy storage module (7) is in static mode; The execution module (9) is specifically used for: when the energy storage module (7) is in the heat storage mode, opening the heat storage shut-off valve (91) and closing the front-end shut-off valve (92), the power unit (74) is controlled according to the system high pressure lookup table, the higher the medium pressure, the greater the speed of the power unit (74), and when the speed of the power unit (74) reaches the maximum value and the medium pressure is still rising, opening the front-end shut-off valve (92); when the energy storage module (7) is in the heat release mode, opening the heat storage shut-off valve (91) and closing the front-end shut-off valve (92), the power unit (74) is controlled according to the system low pressure lookup table, the higher the medium pressure, the greater the speed of the power unit (74), and when the speed of the power unit (74) reaches the maximum value and the medium pressure is still decreasing, opening the front-end shut-off valve (92); when the energy storage module (7) is in the static mode, closing the heat storage shut-off valve (91), opening the front-end shut-off valve (92) and closing the power unit (74).

2. The electric vehicle heat pump thermal storage system according to claim 1, characterized in that: The energy storage device (73) is made of phase change material.

3. The electric vehicle heat pump thermal storage system according to claim 1, characterized in that, The detection module includes a temperature detection unit, which is disposed in the heat-conducting pipe (72) and is used to detect the temperature of the medium in the heat-conducting pipe (72).

4. The electric vehicle heat pump thermal storage system according to claim 1, characterized in that, The control module is also used to update the energy storage percentage based on the status of the energy storage module (7); When the energy storage module (7) is in the heat storage mode, the rotation speed of the power device (74) is obtained, the medium flow rate is calculated, the medium temperature values ​​at the inlet and outlet of the heat conduction pipe (72) are obtained, the instantaneous heat storage power is calculated based on the medium temperature values ​​at the inlet and outlet and the medium flow rate, and the energy storage percentage is generated based on the instantaneous heat storage power and the total heat storage capacity of the energy storage module (7). When the energy storage module (7) is in the heat release mode, the rotation speed of the power device (74) is obtained, the medium flow rate is calculated, the medium temperature values ​​at the inlet and outlet of the heat conduction pipe (72) are obtained, the instantaneous heat release power is calculated based on the medium temperature values ​​at the inlet and outlet and the medium flow rate, and the energy storage percentage is generated based on the instantaneous heat release power and the total heat storage capacity of the energy storage module (7). When the energy storage module (7) is in static mode, the instantaneous heat dissipation power is obtained by looking up a table based on the ambient temperature, and the energy storage percentage is generated based on the instantaneous heat dissipation power and the total heat storage capacity of the energy storage module (7).

5. A heat pump-type thermal storage control method for electric vehicles, applied to a heat pump-type thermal storage system for electric vehicles, wherein the heat pump-type thermal storage system for electric vehicles includes an energy storage module (7), a thermal storage pipeline (8), a control module, and an execution module (9), wherein the energy storage module (7) is connected in parallel to the front-end heat exchanger (3) of the electric vehicle heat pump system through the thermal storage pipeline (8), the energy storage module (7) includes a power unit (74), and the execution module (9) includes a thermal storage shut-off valve (91) connected in series on the thermal storage pipeline (8) and a front-end shut-off valve (92) connected in series with the front-end heat exchanger (3), characterized in that, The method includes: Obtain the status information of the vehicle heat pump system and the energy storage percentage of the energy storage module (7). The status information of the vehicle heat pump system includes the shape of the front heat exchanger (3) and the medium pressure and medium temperature in the pipeline of the vehicle heat pump system. The shape of the front heat exchanger (3) includes the condenser shape in the cooling mode and the evaporator shape in the heating mode. The state of the energy storage module (7) is determined based on the state information and the energy storage percentage, wherein the state of the energy storage module (7) includes heat storage mode, heat release mode and static mode; When the front-end heat exchanger (3) is in the form of a condenser, the energy storage percentage is not 100%, and at least one of the following conditions is met: the medium pressure is greater than a preset first pressure value and the medium temperature is greater than a preset first temperature value, the energy storage module (7) is determined to be in the heat storage mode. When the front-end heat exchanger (3) is in the form of an evaporator, the energy storage percentage is not 0%, and at least one of the following conditions is met: the medium pressure is less than a preset second pressure value and the medium temperature is less than a preset second temperature value, the energy storage module (7) is determined to be in the heat release mode. When the medium pressure is between the first pressure value and the second pressure value and the medium temperature is between the first temperature value and the second temperature value, it is determined that the energy storage module (7) is in static mode; The execution module (9) responds based on the state of the energy storage module (7). When the energy storage module (7) is in the heat storage mode, the heat storage shut-off valve (91) is opened and the front shut-off valve (92) is closed. The power unit (74) is controlled according to the high pressure table of the system. The higher the medium pressure, the greater the speed of the power unit (74). When the speed of the power unit (74) reaches its maximum value and the medium pressure is still rising, the front shut-off valve (92) is opened. When the energy storage module (7) is in the heat release mode, the heat storage shut-off valve (91) is opened and the front shut-off valve (92) is closed. The power unit (74) is controlled according to the low pressure table of the system. The higher the medium pressure, the greater the speed of the power unit (74). When the speed of the power unit (74) reaches its maximum value and the medium pressure is still decreasing, the front shut-off valve (92) is opened. When the energy storage module (7) is in the static mode, the heat storage shut-off valve (91) is closed, the front shut-off valve (92) is opened, and the power unit (74) is closed.

6. The method for controlling heat pump-type thermal storage in electric vehicles according to claim 5, characterized in that, The method further includes: when the energy storage module (7) is in the heat storage mode, obtaining the rotation speed of the power device (74), calculating the medium flow rate, and obtaining the medium temperature values ​​at the inlet and outlet of the heat conduction pipe (72) of the energy storage module (7); calculating the instantaneous heat storage power based on the medium temperature values ​​at the inlet and outlet and the medium flow rate; and generating the energy storage percentage based on the instantaneous heat storage power and the total heat storage capacity of the energy storage module (7).

7. The method for controlling heat pump-type thermal storage in electric vehicles according to claim 5, characterized in that, The method further includes: when the energy storage module (7) is in the heat release mode, obtaining the rotation speed of the power device (74), calculating the medium flow rate, and obtaining the medium temperature values ​​at the inlet and outlet of the heat conduction pipe (72) of the energy storage module (7); calculating the instantaneous heat release power based on the medium temperature values ​​at the inlet and outlet and the medium flow rate; and generating the energy storage percentage based on the instantaneous heat release power and the total heat storage capacity of the energy storage module (7).

8. The method for controlling heat pump-type thermal storage in electric vehicles according to claim 5, characterized in that, The method further includes: when the energy storage module (7) is in static mode, obtaining the instantaneous heat dissipation power by looking up a table based on the ambient temperature; and generating the energy storage percentage based on the instantaneous heat dissipation power and the total heat storage capacity of the energy storage module (7).

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