Solar-air composite heat pump system and control method based on self-sufficient energy storage cascade application

Abstract

The present invention provides a solar-air energy composite heat pump system and a control method based on self-sufficient energy storage cascade application, including a heat pump host module, a solar energy module and a hydraulic module. The solar collector generates hot water and stores it in the energy storage water tank, serving as an external heat source for active jet enthalpy increase to improve the performance of the heat pump. For the heat pump host module, an active jet enthalpy increase device is designed. The refrigerant in the economizer absorbs the heat of the heat storage hot water and is injected into the intermediate pressure chamber of the compressor, converting it into heating capacity and significantly improving the performance of the heat pump. When it is detected that the temperature in the heat storage water tank drops to a certain temperature, the flow direction of the heat storage hot water is switched by using a switching component and pumped to the heat pump fluorine-water heat exchanger for heat exchange to improve the performance of the heat pump and realize the cascade application of the heat storage hot water. The refrigerant flow rates in the fin heat exchanger and the fluorine-water heat exchanger are controlled by their respective electronic expansion valves, and their opening degrees are adjusted according to their respective suction superheat degrees to achieve their respective optimal heat exchange effects.

Description

Technical Field

[0001] The present invention relates to a solar-air energy composite heat pump system, and more specifically, to a solar-air energy composite heat pump system and a control method based on the cascaded application of self-sufficient energy storage. Background Art

[0002] An air source heat pump is a heating device that converts electric energy and air energy into heat through the work of a compressor, achieving the complementarity of electric energy and air energy to generate heating capacity. However, in a low-temperature environment, the heating capacity and energy efficiency decay severely, and it cannot be used in an extremely low-temperature environment. The solutions mainly include solar-assisted air source heat pump technology and jet enthalpy-increasing technology.

[0003] In view of the intermittency of solar energy and the working characteristics of the heat pump, combining solar energy with the heat pump to form a combined cooling, heating and power supply system can achieve the complementarity of multiple energy sources. Currently, it is more common to use a solar heat absorber as an evaporator to absorb solar energy and increase the evaporation temperature, thereby increasing the heating capacity and energy efficiency. From the perspective of application types, it includes direct expansion type, indirect expansion type and composite type, with obvious energy-saving effects, but it cannot be used for refrigeration, only for heating. If the refrigeration function is to be achieved, 2 evaporators need to be designed on the system, and a finned evaporator is used for refrigeration.

[0004] To improve the performance of the heat pump, currently the most common is to adopt the jet enthalpy-increasing technology. Due to its simple structure and low additional cost, it has been commercially applied. Active jet enthalpy increase can utilize an external heat source to improve the performance of the heat pump. However, when the heat of the heat storage hot water is gradually absorbed and utilized, and the water temperature continuously decreases, the effect of active jet enthalpy increase decreases. Summary of the Invention

[0005] In view of this, in order to overcome the above technical defects, the present invention proposes a solar-air energy composite heat pump based on the cascaded application of self-sufficient energy storage. The hot water generated by the solar collector is stored in the energy storage device. When the heat pump operates for heating, the heat storage hot water is pumped to the economizer of the heat pump for active jet enthalpy increase, and the refrigerant is sprayed to convert the heat storage heat into heating capacity in the form of jet enthalpy difference; when it is detected that the temperature in the heat storage water tank drops to a certain temperature, the flow direction of the heat storage hot water is switched by using a switching component and pumped to the fluorine-water heat exchanger on the evaporation side of the heat pump, and the refrigerant and the hot water perform heat exchange to absorb the heat of the heat storage hot water to improve the performance of the heat pump and realize the cascaded application of the heat storage hot water. The refrigerant flow rates in the fin heat exchanger and the fluorine-water heat exchanger are controlled by their respective electronic expansion valves, and their opening degrees are adjusted according to their respective suction superheat degrees to achieve their respective optimal heat exchange effects.

[0006] To solve the above technical problems, the technical solution of the present invention is:

[0007] A solar-air energy composite heat pump system based on the cascaded application of self - contained energy storage includes a heat pump host module, a solar module, and a hydraulic module connected by pipelines. The heat pump host module includes a fin heat exchanger, a fluorine - water heat exchanger, an active jet - enhanced economizer, and a conversion component. The solar module is used to convert solar energy into heat energy and store it in a hot water storage tank.

[0008] The operating states of the heat pump host module include a fin heat exchange state and a fin heat exchange + fluorine - water heat exchange state.

[0009] When the heat pump host module is in the fin heat exchange state and the active jet - enhanced opening condition is met, the conversion component connects the hot water storage tank and the active jet - enhanced economizer, and the hot water in the hot water storage tank serves as the external heat source of the active jet - enhanced economizer. When the active jet - enhanced opening condition is not met, only the conventional heating operation of fin heat exchange is carried out.

[0010] When the heat pump host module is in the fin heat exchange + fluorine - water heat exchange state, the fluorine - water heat exchanger is in parallel with the fin heat exchanger. On the one hand, the refrigerant in the fin heat exchanger exchanges heat with air to absorb air energy. On the other hand, the conversion component connects the hot water storage tank and the fluorine - water heat exchanger to deliver the hot water in the hot water storage tank to the fluorine - water heat exchanger to absorb the heat of the stored - heat hot water.

[0011] Further, the active jet - enhanced economizer includes an active injection inlet pipe and an active injection outlet pipe, and the active injection inlet pipe and the active injection outlet pipe are respectively connected to the outlet and return inlet of the hot water storage tank of the solar module.

[0012] The conversion component includes a jet injection three - way valve and a jet outlet three - way valve.

[0013] The jet injection three - way valve includes an a1 interface, a b1 interface, and a c1 interface. The jet injection three - way valve is connected to the outlet of the hot water storage tank and the active injection inlet pipe through the a1 interface and the b1 interface. The jet injection three - way valve (54) is connected to the outlet of the hot water storage tank and the inlet of the fluorine - water heat exchanger through the a1 interface and the c1 interface.

[0014] The jet outlet three - way valve includes an a2 interface, a b2 interface, and a c2 interface. The jet outlet three - way valve is connected to the inlet of the hot water storage tank and the active injection outlet pipe through the a2 interface and the b2 interface. The jet injection three - way valve is connected to the inlet of the hot water storage tank and the outlet of the fluorine - water heat exchanger through the a2 interface and the c2 interface.

[0015] Further, the heat pump host module includes a variable - frequency compressor, an oil separator, a four - way valve, a fin heat exchanger, and a sub - cooling electronic expansion valve.

[0016] The exhaust pipe of the variable-frequency compressor is connected to the d pipe of the four-way valve through an oil separator. The c pipe of the four-way valve is connected to one end of the fin heat exchanger. The e pipe of the four-way valve is connected to the air pipe of the hydraulic module. The s pipe of the four-way valve is connected to the inlet pipe of the gas-liquid separator. The outlet pipe of the gas-liquid separator is connected to the suction pipe of the variable-frequency compressor. The other end of the fin heat exchanger is connected to the main liquid pipe;

[0017] The active jet enthalpy-increasing economizer is connected with an active injection branch inlet pipe, an active injection branch outlet pipe, an active injection inlet water pipe and an active injection outlet water pipe. Among them, the active injection branch inlet pipe is communicated with the main liquid pipe, and the active injection branch outlet pipe is connected to the intermediate pressure chamber connecting pipe of the variable-frequency compressor.

[0018] Further, the solar energy module includes a solar collector, the hot water storage tank, and a solar hot water pump. A heat storage hot water inlet pipe and a heat storage hot water return pipe are connected between the hot water storage tank and the solar collector, and the solar hot water pump is installed on the heat storage hot water return pipe.

[0019] Further, the heat pump main unit module includes a liquid storage tank, a liquid pipe stop valve and a gas pipe stop valve. The liquid pipe stop valve and the gas pipe stop valve are used to connect the hydraulic module. The gas pipe stop valve is connected to the e pipe of the four-way valve. The liquid pipe stop valve is connected to the liquid storage tank, and the liquid storage tank is connected to one end of the fin heat exchanger.

[0020] The hydraulic module includes a condenser, a buffer tank and a heating water pump. Among them, the gas pipe stop valve is connected to the gas pipe of the condenser, the liquid pipe stop valve is connected to the liquid pipe of the condenser, the heating water pump is connected to the outlet pipe of the condenser, and the buffer tank is connected to the inlet pipe of the condenser.

[0021] Further, it further includes a temperature detection module. The temperature detection module includes an outdoor ambient temperature sensor, an exhaust temperature sensor, a suction temperature sensor, a coil temperature sensor on the fin heat exchanger, a liquid pipe temperature sensor, a water tank temperature sensor, an active jet enthalpy-increasing temperature detection component, a fin heat exchanger inlet temperature sensor, and a fluorine-water heat exchanger inlet temperature sensor;

[0022] The outdoor ambient temperature sensor is used to detect the outdoor ambient temperature T ao , the exhaust temperature sensor is used to detect the exhaust temperature T d , the suction temperature sensor is used to detect the suction temperature T s , the coil temperature sensor is used to detect the coil temperature T def , the liquid pipe temperature sensor is used to detect the liquid pipe temperature T liq0 , the water tank temperature sensor is used to detect the temperature T of the hot water storage tanktank , the fin heat exchanger inlet temperature sensor is used to detect the inlet temperature T of the fin heat exchanger liq1 , the outdoor water - fluorine heat exchanger inlet temperature sensor is used to detect the inlet temperature T of the fluorine - water heat exchanger liq2 .

[0023] A control method for a solar - air energy composite heat pump system based on self - contained energy storage cascade application, providing the solar - air energy composite heat pump system according to any one of the above, the control method includes

[0024] Step S1: Configure a preset opening condition for the conventional heating operation of the fin - type heat exchanger. When the opening condition for the conventional heating operation of the fin - type heat exchanger is met, start the control of the conventional heating operation of the fin - type heat exchanger;

[0025] Step S2A: Configure a preset opening condition for the active jet - enhanced enthalpy operation. When the opening condition for the active jet - enhanced enthalpy operation is met, start the active jet - enhanced enthalpy heating control;

[0026] Step S2B: Configure a preset closing condition for the active jet - enhanced enthalpy operation. When the closing condition for the active jet - enhanced enthalpy operation is met, turn off the active jet - enhanced enthalpy heating control;

[0027] Step S3A: Configure a preset opening condition for the double - evaporator heating operation. When the opening condition for the double - evaporator heating operation is met, start the control of the double - evaporator heating operation;

[0028] Step S3B: Configure a preset closing condition for the double - evaporator heating operation. When the closing condition for the double - evaporator heating operation is met, turn off the control of the double - evaporator heating operation.

[0029] Further: In step S1, when the heat pump main unit module receives a heating start - up instruction and the return water temperature T w,in < the preset return water temperature threshold T w,in,set - the preset return water temperature hysteresis threshold δT w,in , it is regarded as meeting the opening condition for the conventional heating operation of the fin - type heat exchanger.

[0030] Further: In step S2A, when the unit starts the conventional heating operation of the fin - type heat exchanger, when the exhaust gas temperature superheat ΔT d > the preset exhaust gas temperature superheat threshold ΔT d,set1 + the preset exhaust gas temperature superheat hysteresis threshold δT d , and the current water tank temperature T tank > the current liquid pipe temperature T liq0 + the preset opening temperature hysteresis threshold δT liq0When it is, it is regarded as meeting the start condition of the active jet enthalpy - enhanced heating operation;

[0031] In step S2B, when it is detected that the actual exhaust superheat ΔT d ≤ the preset second exhaust superheat threshold value ΔT d,set2 - the preset exhaust superheat hysteresis threshold value δT d When it is, or when it is detected that the inlet temperature T of the heat source side of the active jet enthalpy h,inj,in < the refrigerant outlet temperature T of the active jet enthalpy r,inj,out + the preset first temperature hysteresis threshold value δT h,r,set Or the outlet temperature T of the heat source side of the active jet enthalpy h,inj,out <T r,inj,in + the preset second temperature hysteresis threshold value δT h,r,set2 When it is, it is regarded as meeting the shutdown condition of the active jet enthalpy - enhanced heating operation, and the conventional heating operation is carried out. After 5 minutes, step S2A is judged again.

[0032] Furthermore: In step S3A, when the unit performs the conventional heating operation of fin - type heat exchange and does not meet the start condition of the active jet enthalpy - enhanced heating operation, and the water tank temperature T tank > the outdoor ambient temperature T ao + the preset ambient temperature hysteresis threshold value δT ao When the sum is, it is regarded as meeting the start condition of the double - evaporator heating operation;

[0033] In step S3B, when the unit is in the heating operation, the water tank temperature T tank < the outdoor ambient temperature T ao When it is, it is regarded as meeting the shutdown condition of the double - evaporator heating operation, and the conventional heating operation of fin - type heat exchange is carried out.

[0034] When the outdoor ambient temperature T ao ≤ the water tank temperature T tank ≤ the outdoor ambient temperature T ao + the preset ambient temperature hysteresis threshold value δT ao When it is, maintain the current operating state.

[0035] The technical effects of the present invention are mainly reflected in the following aspects:

[0036] The solar collector panel absorbs solar energy and heats hot water. The hot water that absorbs heat is stored in the energy storage water tank, serving as the external heat source for the active jet enthalpy increase to improve the performance of the heat pump. For the heat pump subsystem, an active jet enthalpy increase device is designed. The refrigerant in the economizer absorbs the heat of the heat storage hot water and is converted into heating capacity, greatly improving the heating capacity and coefficient of performance of the heat pump, and solving the technical bottleneck that the heat pump cannot be applied in extremely low temperature environments; when it is detected that the temperature in the heat storage water tank drops to a certain temperature, the flow direction of the heat storage hot water is switched by using the switching component and pumped to the evaporation side of the heat pump to absorb the heat storage heat, so as to improve the performance of the heat pump and realize the cascade application of the heat storage hot water. The refrigerant flow rates in the fin heat exchanger and the fluorine-water heat exchanger are controlled by their respective electronic expansion valves, and their opening degrees are adjusted according to their respective suction superheats to achieve their respective optimal heat exchange effects. Description of the Drawings

[0037] Figure 1 : System schematic diagram of the solar-air energy composite heat pump system based on self-sufficient energy storage cascade application;

[0038] Figure 2 : Schematic diagram of the system flow path of the solar-air energy composite heat pump system based on self-sufficient energy storage cascade application in the active jet enthalpy heating operation mode;

[0039] Figure 3 : Schematic diagram of the system flow path of the solar-air energy composite heat pump system based on self-sufficient energy storage cascade application in the fin heat exchange conventional heating operation mode;

[0040] Figure 4 : Schematic diagram of the system flow path of the solar-air energy composite heat pump system based on self-sufficient energy storage cascade application in the double evaporator heating mode;

[0041] Figure 5 : Schematic diagram of the distribution positions of the active jet enthalpy economizer and the active jet enthalpy temperature detection component;

[0042] Figure 6 : Schematic diagram of the process of the control method of the solar-air energy composite heat pump system based on self-sufficient energy storage cascade application.

[0043] Reference Signs:

[0044] 1. Variable frequency compressor; 2. High-pressure pressure sensor; 3. Oil separator; 4. Four-way valve; 5. Finned heat exchanger; 6. First main electronic expansion valve; 7. Liquid storage tank; 8. Liquid pipe stop valve; 9. Gas pipe stop valve; 10. Gas-liquid separator; 11. Subcooling electronic expansion valve; 12. Active jet enthalpy-increasing economizer; 13. Inlet pipe of active jet branch pipe; 14. Outlet pipe of active jet branch pipe; 21. Solar collector; 22. Solar hot water pump; 31. Hot water storage tank; 32. Jet enthalpy-increasing hot water pump; 33. Inlet pipe of active jet; 34. Outlet pipe of active jet; 35. Make-up water valve; 36. Drain valve; 41. Condenser; 42. Buffer tank; 43. Heating water pump; 51. Fluorine-water heat exchanger; 52. Second main electronic expansion valve; 54. Three-way valve for jet inlet water; 55. Three-way valve for jet outlet water. Detailed implementation manners

[0045] The following further details the specific implementation manners of the present invention in conjunction with the accompanying drawings, so that the technical solutions of the present invention are easier to understand and master.

[0046] Embodiment:

[0047] Referring to Figure 1 As shown, a solar-air energy composite heat pump system based on self-sufficient energy storage cascade application includes a heat pump host module, a solar energy module and a hydraulic module. The outdoor unit module includes a variable frequency compressor 1, an oil separator 3, a four-way valve 4, a finned heat exchanger 5, a first main electronic expansion valve 6, an active jet enthalpy-increasing economizer and a subcooling electronic expansion valve 11.

[0048] The exhaust pipe of the variable frequency compressor 1 is connected to the d pipe of the four-way valve 4 through the oil separator 3. The c pipe of the four-way valve 4 is connected to one end of the finned heat exchanger 5. The e pipe of the four-way valve 4 is connected to the gas pipe of the hydraulic module. The s pipe of the four-way valve 4 is connected to the inlet pipe of the gas-liquid separator 10. The outlet pipe of the gas-liquid separator 10 is connected to the suction pipe of the variable frequency compressor 1. The other end of the finned heat exchanger 5 is connected to the main liquid pipe.

[0049] The active jet enthalpy-increasing economizer 12 is connected with an inlet pipe 13 of the active jet branch pipe, an outlet pipe 14 of the active jet branch pipe, an inlet pipe 33 of the active jet and an outlet pipe 34 of the active jet. Among them, the inlet pipe 13 of the active jet branch pipe is communicated with the main liquid pipe. The outlet pipe 14 of the active jet branch pipe is connected to the intermediate pressure chamber connecting pipe of the variable frequency compressor 1. The inlet pipe 33 of the active jet and the outlet pipe 34 of the active jet are respectively connected to the water outlet and water return ports of the hot water storage tank 31. A jet enthalpy-increasing hot water pump 32 is installed on the inlet pipe 33 of the active jet. A heat storage hot water inlet pipe and a heat storage hot water return pipe are connected between the heat exchange flow channels of the hot water storage tank 31 and the solar collector 21. A solar hot water pump 22 is installed on the heat storage hot water return pipe for pumping cooling water to flow between the hot water storage tank 31 and the solar heat collecting panel.

[0050] The heat pump main unit module includes a fin heat exchanger 5, a fluorine-water heat exchanger 51, an active jet enthalpy economizer 12 and a conversion component. The solar energy module is used to convert solar energy into heat energy and store it in the hot water storage tank 31;

[0051] The heating and heat exchange modes of the heat pump main unit module include a fin heat exchange mode and a fin heat exchange + fluorine-water heat exchange mode.

[0052] When the heat pump main unit module is in the fin heat exchange mode, the conversion component connects the hot water storage tank 31 and the active jet enthalpy economizer 12. When the active jet enthalpy opening condition is met, the hot water in the hot water storage tank 31 serves as the external heat source of the active jet enthalpy economizer 12; when the active jet enthalpy opening condition is not met, a conventional heating operation mode of fin heat exchange is carried out.

[0053] When the heat pump main unit module is in the fin heat exchange + fluorine-water heat exchange state, the fluorine-water heat exchanger 51 is connected in parallel with the fin heat exchanger 5, and the conversion component connects the hot water storage tank 31 and the fluorine-water heat exchanger 51 to transport the hot water in the hot water storage tank 31 to the fluorine-water heat exchanger 51 to absorb air energy.

[0054] The active jet enthalpy economizer 12 includes an active injection inlet pipe 33 and an active injection outlet pipe 34. The active injection inlet pipe 33 and the active injection outlet pipe 34 are respectively connected to the outlet and return water ports of the hot water storage tank 31 of the solar energy module.

[0055] The conversion component includes an injection inlet three-way valve 54 and an injection outlet three-way valve 55.

[0056] The injection inlet three-way valve 54 includes an a1 interface, a b1 interface and a c1 interface. The injection inlet three-way valve 54 is connected to the outlet of the hot water storage tank 31 and the active injection inlet pipe 33 through the a1 interface and the b1 interface. The injection inlet three-way valve 54 is connected to the outlet of the hot water storage tank 31 and the inlet of the fluorine-water heat exchanger 51 through the a1 interface and the c1 interface.

[0057] The injection outlet three-way valve 55 includes an a2 interface, a b2 interface and a c2 interface. The injection outlet three-way valve 55 is connected to the inlet of the hot water storage tank 31 and the active injection outlet pipe 34 through the a2 interface and the b2 interface. The injection inlet three-way valve 54 is connected to the inlet of the hot water storage tank 31 and the outlet of the fluorine-water heat exchanger 51 through the a2 interface and the c2 interface.

[0058] The heat pump main unit module includes a liquid storage tank 7, a liquid pipe stop valve 8 and a gas pipe stop valve 9. The liquid pipe stop valve 8 and the gas pipe stop valve 9 are used to connect to the hydraulic module. The gas pipe stop valve 9 is connected to the e pipe of the four-way valve 4. The outlet pipe of the liquid pipe stop valve 8 is connected to the inlet pipe of the liquid storage tank 7. The outlet pipe of the liquid storage tank 7 is connected to one end of the fin heat exchanger 5.

[0059] The hydraulic module includes a condenser 41, a buffer tank 42 and a heating water pump 43. Among them, the gas pipe stop valve 9 is connected to the gas pipe of the condenser 41, the liquid pipe stop valve 8 is connected to the liquid pipe of the condenser 41, the heating water pump 43 is connected to the outlet water pipe of the condenser 41, and the buffer tank 42 is connected to the inlet water pipe of the condenser 41.

[0060] The hot water storage tank 31 is connected with a water replenishing valve 35 and a drain valve 36. The drain valve 36 is used for sewage discharge, and the water replenishing valve 35 is used to supplement water into the hot water storage tank 31.

[0061] It also includes a temperature detection module. The temperature detection module includes an outdoor ambient temperature sensor, an exhaust temperature sensor, a suction temperature sensor, a coil temperature sensor on the fin heat exchanger 5, a liquid pipe temperature sensor, a water tank temperature sensor, a fin heat exchanger inlet temperature sensor, a fluorine-water heat exchanger inlet temperature sensor and an active jet enthalpy increase temperature detection component. The outdoor ambient temperature sensor is used to detect the outdoor ambient temperature T ao , the exhaust temperature sensor is used to detect the exhaust temperature T d , the suction temperature sensor is used to detect the suction temperature T s , the coil temperature sensor is used to detect the coil temperature T def , the liquid pipe temperature sensor is used to detect the liquid pipe temperature T liq0 , the water tank temperature sensor is used to detect the temperature T of the hot water storage tank 31 tank, The fin heat exchanger inlet temperature sensor is used to detect the inlet temperature T of the fin heat exchanger 5 liq1 , the outdoor water-fluorine heat exchanger inlet temperature sensor is used to detect the inlet temperature T of the fluorine-water heat exchanger 51 liq2 .

[0062] The active jet enthalpy increase temperature detection component includes a jet enthalpy increase inlet water temperature sensor, a jet enthalpy increase outlet water temperature sensor, a refrigerant injection inlet pipe temperature sensor, and a refrigerant injection outlet pipe temperature sensor. The refrigerant injection inlet pipe temperature sensor is used to detect the active jet enthalpy increase refrigerant inlet temperature T r,inj,in , the refrigerant injection outlet pipe temperature sensor is used to detect the active jet enthalpy increase refrigerant outlet temperature T r,inj,out , the jet enthalpy increase inlet water temperature sensor is used to detect the active jet enthalpy increase heat source side inlet temperature T h,inj,in , the jet enthalpy increase outlet water temperature sensor is used to detect the active jet enthalpy increase heat source side outlet temperature T h,inj,out .

[0063] The hydraulic module includes an inlet water temperature sensor and an outlet water temperature sensor. The inlet water temperature sensor is used to detect the inlet water temperature T of the condenser. w,in , the outlet water temperature sensor is used to detect the outlet water temperature T of the condenser w,out .

[0064] The heat pump system involved in this application has 4 operating modes, namely:

[0065] 1) Cooling operation mode; 2) Active jet enthalpy increase heating operation mode; 3) Fin heat exchange conventional heating mode; 4) Dual evaporator heating mode.

[0066] 1) Refrigeration operation mode

[0067] In the cooling operation mode, the fluorine-water heat exchanger does not participate in the cooling operation.

[0068] 2) Active jet enthalpy heating operation mode

[0069] In the active jet enthalpy heating operation mode, the hot water is generated by solar heat storage through the arrangement of the hot water storage tank 31 and the solar collector 21, and stored in the hot water storage tank 31. In this mode, the direction from the a1 interface to the b1 interface of the jet water inlet three-way valve 54 is connected, and the direction from the a1 interface to the c1 interface is closed, and the direction from the b2 interface to the a2 interface of the jet water outlet three-way valve 55 is connected, and the direction from the c2 interface to the a2 interface is closed, and the jet enthalpy hot water pump 32 pumps the stored hot water to circulate between the hot water storage tank 31 and the active jet enthalpy economizer 12. For the flow diagram, refer to Figure 2 The high-temperature gaseous refrigerant discharged from the variable frequency compressor 1 passes through the oil separator 3, the d pipe of the four-way valve 4, the e pipe of the four-way valve 4, and the gas pipe stop valve 9 to enter the hydraulic module for heat exchange. After releasing the heat, the refrigerant passes through the liquid pipe stop valve 8 and the liquid storage tank 7. A part of the refrigerant flows through the main liquid pipe: passes through the first main electronic expansion valve 6, the fin heat exchanger 5, the c pipe of the four-way valve 4, the s pipe of the four-way valve 4, and passes through the gas-liquid separator 10 to return to the variable frequency compressor 1; the other part of the refrigerant passes through the subcooling electronic expansion valve 11 for throttling, enters the active jet enthalpy increase economizer 12 through the active jet branch pipe inlet pipe 13, exchanges heat with the hot water in the hot water storage tank, and returns to the variable frequency compressor 1 through the active jet branch pipe outlet pipe 14.

[0070] 3) Conventional heating mode of fin heat exchange

[0071] In normal heating mode, refer to the flow diagram Figure 3, the high-temperature gaseous refrigerant discharged from the variable-frequency compressor 1 enters the hydraulic module through the oil separator 3, the d pipe of the four-way valve 4, the e pipe of the four-way valve 4, and the gas pipe stop valve 9 for heat exchange. After releasing heat, the refrigerant passes through the liquid pipe stop valve 8 and the liquid storage tank 7, and then the refrigerant is divided into two paths after passing through the main liquid pipe. One path passes through the first main electronic expansion valve 6 and the fin heat exchanger 5, and the other path passes through the second main electronic expansion valve 52 and the fluorine-water heat exchanger 51 and then converges. After passing through the c pipe of the four-way valve 4, the s pipe of the four-way valve 4, and passing through the gas-liquid separator 10, it returns to the variable-frequency compressor 1. At this time, the jet enthalpy increase hot water pump 32 pumps hot water through the a1 interface and the c1 interface of the injection water three-way valve 54 and flows to the fluorine-water heat exchanger 51. The refrigerant in the fluorine-water heat exchanger absorbs the heat of the heat storage hot water to improve the heat pump performance, realizes the cascade application of the heat storage hot water, and then returns to the heat storage water tank 31 through the c2 interface and the a2 interface of the injection water three-way valve 55.

[0072] 4) Dual-evaporator heating mode

[0073] The hot water in the heat storage water tank 31 gradually decreases in temperature as the active jet enthalpy increase progresses. When the water tank temperature sensor detects that the hot water temperature in the water tank has decreased to a certain temperature, the effect of the active jet enthalpy increase decreases. At this time, the working state of the heat pump main module switches to the dual-evaporator heating mode. In the dual-evaporator heating mode, the a1 interface to the c1 interface direction of the injection water three-way valve 54 is conducted, and the a1 interface to the b1 interface direction is closed. The c2 interface to the a2 interface direction of the injection water three-way valve 55 is conducted, and the b2 interface to the a2 interface direction is closed. The jet enthalpy increase hot water pump 32 pumps the heat storage hot water to circulate between the heat storage water tank 31 and the fluorine-water heat exchanger 51.

[0074] Refer to the flow path diagram Figure 4 , the high-temperature gaseous refrigerant discharged from the variable-frequency compressor 1 enters the hydraulic module through the oil separator 3, the d pipe of the four-way valve 4, the e pipe of the four-way valve 4, and the gas pipe stop valve 9 for heat exchange. After releasing heat, the refrigerant passes through the liquid pipe stop valve 8 and the liquid storage tank 7. After that, the refrigerant is divided into two paths after passing through the main liquid pipe. One path passes through the first main electronic expansion valve 6 and the fin heat exchanger 5, and the other path passes through the second main electronic expansion valve 52 and the fluorine-water heat exchanger 51 and then converges. After passing through the c pipe of the four-way valve 4, the s pipe of the four-way valve 4, and passing through the gas-liquid separator 10, it returns to the variable-frequency compressor 1. At this time, the jet enthalpy increase hot water pump 32 pumps hot water through the a1 interface and the c1 interface of the injection water three-way valve 54 and flows to the fluorine-water heat exchanger 51. The refrigerant in the fluorine-water heat exchanger absorbs the heat of the heat storage hot water to improve the heat pump performance, realizes the cascade application of the heat storage hot water, and then returns to the heat storage water tank 31 through the c2 interface and the a2 interface of the injection water three-way valve 55.

[0075] Please refer to Figure 6 , a control method for a solar-air energy composite heat pump system based on the cascade application of self-sufficient energy storage, including

[0076] Step S1: Configure a preset conventional heating operation start condition. When the conventional heating operation start condition is satisfied, start the conventional heating operation control;

[0077] Step S2A: Configure a preset active jet enthalpy increase operation start condition. When the active jet enthalpy increase operation start condition is satisfied, start the active jet enthalpy increase heating control;

[0078] Step S2B: It is configured with a preset active jet enthalpy - increase operation shutdown condition. When the active jet enthalpy - increase operation shutdown condition is met, the active jet enthalpy - increase heating control is shut down;

[0079] Step S3A: It is configured with a preset dual - evaporator heating operation start condition. When the dual - evaporator heating operation start condition is met, the dual - evaporator heating operation control is started;

[0080] Step S3B: It is configured with a preset dual - evaporator heating operation shutdown condition. When the dual - evaporator heating operation shutdown condition is met, the dual - evaporator heating operation control is shut down.

[0081] The control content will be described in detail below according to the operation modes.

[0082] 1. Finned - tube heat - exchange conventional heating operation mode

[0083] 1.1 Start condition

[0084] The finned - tube heat - exchange conventional heating operation start condition includes: when a heating start - up instruction is received and the return water temperature T w,in <the preset return water temperature T w,in,set - the preset return water temperature difference threshold δT w,in , the unit starts the heating operation.

[0085] 1.2 Control content

[0086] When the unit starts to operate, the first main electronic expansion valve 6 is opened to a certain initial opening. After operating for t minutes, the opening is adjusted according to the suction superheat degree corresponding to the finned - tube heat exchanger. Here, the suction superheat degree of the finned - tube heat exchanger is defined as ΔT s1, =T s -T liq1 . When the actual suction superheat degree value ΔT s is greater than the target superheat degree ΔT s1,set + the preset suction superheat degree return - difference threshold δT s1 , the opening of the first main electronic expansion valve 6 increases. When the actual suction superheat degree value ΔT s is less than the target superheat degree ΔT s1set - the suction superheat degree return - difference threshold δT s1 , the opening of the first main electronic expansion valve 6 decreases.

[0087] When the actual suction superheat degree value ΔT s is between the target superheat degree ΔT s1,set - the preset suction superheat degree return - difference threshold δT s1 and ΔT s1,set + the preset suction superheat degree return - difference threshold δT s1When it is between them, the opening degree of the first main electronic expansion valve 6 remains unchanged at the current opening degree.

[0088] 2. Active jet enthalpy-increasing heating operation mode

[0089] 2.1 Opening conditions

[0090] Exhaust superheat ΔT d It is defined as the exhaust temperature detected by the exhaust temperature sensor minus the saturation temperature corresponding to the high-pressure detected by the high-pressure pressure sensor 2.

[0091] The unit performs conventional fin heat exchange heating operation, and the current exhaust superheat ΔT d is greater than the preset first exhaust superheat ΔT d,set1 and the preset exhaust superheat hysteresis threshold δT d The sum, and the current water tank temperature T tank is greater than the current liquid pipe temperature T liq0 and the preset opening temperature hysteresis threshold δT liq0 When the sum is reached, it is regarded as meeting the opening conditions for active jet enthalpy-increasing heating operation. That is: if the current exhaust superheat ΔT d > the preset first exhaust superheat ΔT d,set1 + the preset exhaust superheat hysteresis threshold δT d , and the current water tank temperature T tank > the current liquid pipe temperature T liq0 + the preset temperature hysteresis threshold δT liq0 , start the active jet enthalpy-increasing heating operation, open the corresponding subcooling electronic expansion valve 11, and the initial opening degree V open2 , use the hot water in the external hot water storage tank 31 as the heat source for the active jet enthalpy-increasing, and the jet enthalpy hot water pump 32 is turned on, and the water flow rate is kept constant at Y m 3 / h.

[0092] 2.2 Control content

[0093] The active jet enthalpy-increasing opening control strategy takes a certain jet superheat value as the control target, and the active jet enthalpy-increasing opening control strategy includes a configured target jet superheat value and a superheat hysteresis value. The jet superheat ΔT inj is defined as the jet refrigerant outlet temperature T r,inj,out minus the jet refrigerant inlet temperature T r,inj,in .

[0094] After running for the preset set duration, when the current jet superheat ΔT inj is greater than the preset target jet superheat threshold T inj,set and the preset superheat hysteresis threshold δT injWhen the sum is reached, the opening of the subcooled electronic expansion valve 11 is controlled to increase; that is: when the current actual injection superheat ΔT inj >ΔT inj,set + superheat return difference value δT inj , the opening of the subcooled electronic expansion valve 11 increases;

[0095] When the current injection superheat ΔT inj is less than the difference between the target injection superheat value ΔT inj,set and the superheat return difference threshold value δT inj , the opening of the subcooled electronic expansion valve 11 is controlled to decrease; that is: when the actual injection superheat ΔT inj <ΔT inj,set - superheat return difference threshold value δT inj , the opening of the subcooled electronic expansion valve 11 decreases;

[0096] When the current injection superheat ΔT inj is between the difference between the target injection superheat value ΔT in,set and the preset superheat return difference threshold value δT inj and the sum of the target injection superheat value and the preset superheat return difference threshold value, the opening of the subcooled electronic expansion valve 11 remains unchanged. That is: when the set value ΔT inj,set - superheat return difference threshold value δT in ≤ actual injection superheat ΔT inj ≤ΔT inj,set + superheat return difference value δT inj , the subcooled electronic expansion valve 11 remains unchanged.

[0097] 2.3 Closing conditions

[0098] Closing of the active jet enthalpy increase:

[0099] The closing condition of the active jet enthalpy increase configures a preset second exhaust superheat threshold value ΔT d,set2 (ΔT d,set2 <ΔT d,set1 ), when the exhaust superheat ΔT d is less than the difference between the preset second exhaust superheat threshold value ΔT d,set,2 and the preset exhaust superheat return difference threshold value δT d , it is regarded as meeting the closing condition of the active jet enthalpy increase; that is: when the detected actual exhaust superheat ΔT d ≤ preset exhaust superheat threshold value ΔT d,set2 -δT d , the subcooled electronic expansion valve 11 closes and the active jet enthalpy increase stops running.

[0100] The closing condition of the active jet enthalpy increase is also configured with a first temperature return difference threshold value δT h,r,set1and the second temperature difference threshold δT h,r,set2 , when the inlet temperature T of the active jet enthalpy heat source side h,inj,in is less than the outlet temperature T of the active jet enthalpy refrigerant r,inj,out plus the preset first temperature difference threshold δT h,r,set1 , or when the outlet temperature T of the active jet enthalpy heat source side h,inj,out is less than the inlet temperature T of the active jet enthalpy refrigerant r,inj,in plus the preset second temperature difference threshold δT h,r,set2 , it is regarded as meeting the active jet enthalpy closing condition; that is: when it is detected that T h,inj,in < T r,inj,out +δT h,r,set1 or T h,inj,out < T r,inj,in +δT h,r,set2 , it is determined that the unit can no longer effectively utilize the external heat source to increase the heat production, and immediately close the jet enthalpy hot water pump 32, and adjust the opening of the subcooling electronic expansion valve 11 to 0 steps.

[0101] After the active jet enthalpy heating operation is closed, the fin type conventional heating operation is carried out, and the S2A determination is carried out again after 5 minutes.

[0102] 3. Dual evaporator heating operation

[0103] 3.1 Opening conditions

[0104] The opening conditions for the dual evaporator heating operation: the unit is in heating operation and meets the following conditions: it does not meet the above active jet enthalpy opening operation conditions, and the water tank temperature T tank > the outdoor ambient temperature T ao plus the preset ambient temperature difference threshold δT ao .

[0105] 3.2 Control content

[0106] When the outdoor ambient temperature T ao ≤ the water tank temperature T tank ≤ the outdoor ambient temperature T ao plus the set ambient temperature difference threshold δT ao , maintain the current heating operation, where the current heating operation refers to the dual evaporator heating operation or the fin type heat exchange conventional heating operation. For example, when in the fin type heat exchange conventional heating operation and the above conditions are detected, the fin type heat exchange conventional heating operation is maintained; when in the dual evaporator heating operation and the above conditions are detected, the dual evaporator heating operation is maintained.

[0107] The opening degrees of the first main electronic expansion valve 6 and the second main electronic expansion valve 52 are independently controlled.

[0108] The opening degree of the first main electronic expansion valve 6 is controlled according to the content of 1.2, and the second main electronic expansion valve 52 controls the opening degree according to the corresponding suction superheat degree.

[0109] The second main electronic expansion valve 52 is opened at a certain initial opening degree. After running for an initial running duration of t minutes, the opening degree is adjusted according to the suction superheat degree corresponding to the fluorine-water heat exchanger 51, and the target suction superheat degree is ΔT s2,set =T s -T liq2 。

[0110] When the actual suction superheat degree value ΔT s is greater than the target suction superheat degree ΔT s2,setset + the preset suction superheat degree deadband threshold δT s2 , the opening degree of the second main electronic expansion valve 52 increases;

[0111] When the actual suction superheat degree value ΔT s is less than the target suction superheat degree ΔT s2,setset - the preset suction superheat degree deadband threshold δT s2 , the opening degree of the second main electronic expansion valve 52 decreases;

[0112] When the actual suction superheat degree value ΔT s is between the target suction superheat degree ΔT s2,setset - the preset suction superheat degree deadband threshold δT s2 and the target suction superheat degree ΔT s2,setset + the preset suction superheat degree deadband threshold δT s2 , the opening degree of the second main electronic expansion valve 52 remains unchanged at the current opening degree.

[0113] 3.3 Closing conditions

[0114] In the above heating operation mode, when the water tank temperature T tank <the outdoor ambient temperature T ao , it is regarded as meeting the closing conditions of the dual-evaporator heating operation, and the finned heat exchange conventional heating operation is carried out.

[0115] Of course, the above are only typical examples of the present invention. In addition, the present invention can also have many other specific implementation manners. Any technical solutions formed by equivalent substitution or equivalent transformation fall within the scope of protection required by the present invention.

Claims

1. A solar-air energy composite heat pump system based on the cascaded application of self-sufficient energy storage, characterized in that: It includes a heat pump host module, a solar energy module and a hydraulic module connected through pipelines. The heat pump host module includes a fin heat exchanger (5), a fluorine-water heat exchanger (51), an active ejector economizer (12) and a conversion component. The solar energy module is used to convert solar energy into heat energy and store it in a hot water storage tank (31). The operating states of the heat pump host module include a fin heat exchange state and a fin heat exchange + fluorine-water heat exchange state. When the heat pump host module is in the fin heat exchange state, the conversion component connects the hot water storage tank (31) and the active ejector economizer (12), and the hot water in the hot water storage tank (31) serves as the external heat source of the active ejector economizer (12). When the heat pump host module is in the fin heat exchange + fluorine-water heat exchange state, the fluorine-water heat exchanger (51) is connected in parallel with the fin heat exchanger (5). On the one hand, the refrigerant in the fin heat exchanger exchanges heat with air to absorb air energy. On the other hand, the conversion component connects the hot water storage tank (31) and the fluorine-water heat exchanger (51), and conveys the hot water in the hot water storage tank (31) to the fluorine-water heat exchanger (51) to absorb the heat of the stored hot water. The active ejector economizer (12) is connected with an active ejector branch inlet pipe (13), an active ejector branch outlet pipe (14), an active ejector inlet pipe (33) and an active ejector outlet pipe (34). Among them, the active ejector branch inlet pipe (13) is communicated with the main liquid pipe, the active ejector branch outlet pipe (14) is connected to the intermediate pressure chamber connecting pipe of the variable frequency compressor (1), and the active ejector inlet pipe (33) and the active ejector outlet pipe (34) are respectively connected to the water outlet and water return port of the hot water storage tank (31) of the solar energy module. The conversion component includes an injection water three-way valve (54) and an injection water outlet three-way valve (55). The injection water three-way valve (54) includes an a1 interface, a b1 interface and a c1 interface. The injection water three-way valve (54) is connected to the water outlet of the hot water storage tank (31) and the active ejector inlet pipe (33) through the a1 interface and the b1 interface, and the injection water three-way valve (54) is connected to the water outlet of the hot water storage tank (31) and the water inlet of the fluorine-water heat exchanger (51) through the a1 interface and the c1 interface. The injection water outlet three-way valve (55) includes an a2 interface, a b2 interface and a c2 interface. The injection water outlet three-way valve (55) is connected to the water inlet of the hot water storage tank (31) and the active ejector outlet pipe (34) through the a2 interface and the b2 interface, and the injection water inlet three-way valve (54) is connected to the water inlet of the hot water storage tank (31) and the water outlet of the fluorine-water heat exchanger (51) through the a2 interface and the c2 interface.

2. The solar-air energy composite heat pump system based on self-sufficient energy storage cascade application according to claim 1, characterized in that: The heat pump host module includes a variable frequency compressor (1), an oil separator (3), a four-way valve (4), a fin heat exchanger (5), a subcooling electronic expansion valve (11). The exhaust pipe of the variable-frequency compressor (1) is connected to the d pipe of the four-way valve (4) through an oil separator (3). The c pipe of the four-way valve (4) is connected to one end of the finned heat exchanger (5). The e pipe of the four-way valve (4) is connected to the air pipe of the hydraulic module. The s pipe of the four-way valve (4) is connected to the inlet pipe of the gas-liquid separator (10). The outlet pipe of the gas-liquid separator (10) is connected to the suction pipe of the variable-frequency compressor (1). The other end of the finned heat exchanger (5) is connected to the main liquid pipe.

3. The solar-air energy composite heat pump system based on self-sufficient energy storage cascade application according to claim 1, characterized in that: The solar module includes a solar collector (21), the hot water storage tank (31), and a solar hot water pump (22). A heat storage hot water inlet pipe and a heat storage hot water return pipe are connected between the hot water storage tank (31) and the solar collector (21). The solar hot water pump (22) is installed on the heat storage hot water return pipe.

4. The solar-air energy composite heat pump system based on the self-sufficient energy storage cascade application as claimed in claim 1, wherein: The heat pump main module includes a liquid storage tank (7), a liquid pipe stop valve (8), and a gas pipe stop valve (9). The liquid pipe stop valve (8) and the gas pipe stop valve (9) are used to connect to the hydraulic module. The gas pipe stop valve (9) is connected to the e pipe of the four-way valve (4). The liquid pipe stop valve (8) is connected to the liquid storage tank (7). The liquid storage tank (7) is connected to one end of the finned heat exchanger (5). The hydraulic module includes a condenser (41), a buffer tank (42), and a heating water pump (43). The gas pipe stop valve (9) is connected to the gas pipe of the condenser (41). The liquid pipe stop valve (8) is connected to the liquid pipe of the condenser (41). The heating water pump (43) is connected to the outlet pipe of the condenser (41). The buffer tank (42) is connected to the inlet pipe of the condenser (41).

5. The solar-air energy composite heat pump system based on the self-sufficient energy storage cascade application as claimed in claim 1, wherein: It further includes a temperature detection module. The temperature detection module includes an outdoor ambient temperature sensor, an exhaust temperature sensor, a suction temperature sensor, a coil temperature sensor on the finned heat exchanger, a liquid pipe temperature sensor, a water tank temperature sensor, an active jet enthalpy increase temperature detection component, a finned heat exchanger inlet temperature sensor, and a fluorine-water heat exchanger inlet temperature sensor. The outdoor ambient temperature sensor is used to detect the outdoor ambient temperature T ao , the exhaust gas temperature sensor is used to detect the exhaust gas temperature T d , the suction temperature sensor is used to detect the suction temperature T s , the coil temperature sensor is used to detect the coil temperature T def , the liquid pipe temperature sensor is used to detect the liquid pipe temperature T liq0 , the water tank temperature sensor is used to detect the temperature T of the hot water storage tank tank , the fin heat exchanger inlet temperature sensor is used to detect the inlet temperature T of the fin heat exchanger (5) liq1 , the outdoor water - fluorine heat exchanger inlet temperature sensor is used to detect the inlet temperature T of the fluorine - water heat exchanger (51) liq2 .

6. Control method of a solar-air energy composite heat pump system based on self-sufficient energy storage cascade application, providing a solar-air energy composite heat pump system based on self-sufficient energy storage cascade application as described in any one of claims 1-5, characterized in that: The control method includes Step S1: Configure preset opening conditions for the conventional heating operation of the finned heat exchange. When the opening conditions for the conventional heating operation of the finned heat exchange are met, start the control for the conventional heating operation of the finned heat exchange. Step S2A: Configure preset opening conditions for the active jet enthalpy increase operation. When the opening conditions for the active jet enthalpy increase operation are met, start the active jet enthalpy increase heating control. Step S2B: Configure preset closing conditions for the active jet enthalpy increase operation. When the closing conditions for the active jet enthalpy increase operation are met, stop the active jet enthalpy increase heating control. Step S3A: Configure preset opening conditions for the double evaporator heating operation. When the opening conditions for the double evaporator heating operation are met, start the control for the double evaporator heating operation. Step S3B: Configure preset closing conditions for the double evaporator heating operation. When the closing conditions for the double evaporator heating operation are met, stop the control for the double evaporator heating operation.

7. The control method of the solar-air energy composite heat pump system based on the self-sufficient energy storage cascade application according to claim 6, characterized in that: In step S1, when the heat pump main unit module receives a heating start-up instruction and the return water temperature T w,in <is less than the preset return water temperature threshold value T w,in,set - the preset return water temperature differential threshold value δT w,in , it is regarded as meeting the opening condition for the normal heating operation of the finned heat exchanger.

8. The control method of the solar-air energy composite heat pump system based on self-sufficient energy storage cascade application according to claim 6, characterized in that: In step S2A, when the unit starts the fin - type heat exchange for conventional heating operation, when the current exhaust superheat ΔT d > the preset first exhaust superheat ΔT d,set1 + the preset exhaust superheat return difference threshold δT d , and the current water tank temperature T tank > the current liquid pipe temperature T liq0 + the preset opening temperature return difference threshold δT liq0 , it is regarded as meeting the active jet - enhanced enthalpy heating operation start condition; In step S2B, when the unit operates in active jet enthalpy increase heating mode, when it is detected that the actual exhaust superheat ΔT d ≤ the preset second exhaust superheat threshold ΔT d,set2 - the preset exhaust superheat hysteresis threshold δT d or when it is detected that the inlet temperature T of the heat source side of the active jet enthalpy increase h,inj,in < the refrigerant outlet temperature T of the active jet enthalpy increase r,inj,out + the preset first temperature hysteresis threshold δT h,r,set or the outlet temperature T of the heat source side of the active jet enthalpy increase h,inj,out <T r,inj,in + the preset second temperature hysteresis threshold δT h,r,set2 it is regarded as meeting the shutdown condition for active jet enthalpy increase heating operation.

9. The control method of the solar-air energy composite heat pump system based on the self-sufficient energy storage cascade application as claimed in claim 6, wherein: In step S3A, when the unit is operating in the conventional fin-tube heat exchange heating mode and does not meet the active jet enthalpy-increasing heating operation start-up condition, and the water tank temperature T tank > the outdoor ambient temperature T ao + the preset ambient temperature return difference threshold δT ao it is regarded as meeting the start-up condition for the dual-evaporator heating operation; In step S3B, when the unit is operating in heating mode, the water tank temperature T tank <outdoor ambient temperature T ao , it is regarded as meeting the shutdown condition for the double-evaporator heating operation, and the fin heat exchanger operates in normal heating mode.

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