A thermal energy supply system

Abstract

The application discloses a heat energy supply system, which comprises an air source heat pump unit, a water storage mechanism and a water source high-temperature heat pump; the water storage mechanism comprises a medium-temperature heat storage water tank and a high-temperature heat storage water tank; the air source heat pump unit prepares medium-temperature hot water which is stored in the medium-temperature heat storage water tank; the hot water in the medium-temperature heat storage water tank can supply hot water to the outside or serve as a heat source of the water source high-temperature heat pump unit to prepare high-temperature hot water; the high-temperature hot water is stored in the high-temperature heat storage water tank and can supply high-temperature hot water to the outside or enter a flash evaporator to flash evaporate to obtain micro-pressure steam which is compressed by a water vapor compressor and then output high-temperature steam. The application has the beneficial effects that the medium-temperature and high-temperature hot water supply can be realized at the same time, the high-temperature hot water can provide high-temperature steam after being compressed by flash evaporation, and the medium-temperature heat storage water tank and the high-temperature heat storage water tank are used in cooperation, so that the fluctuation of heat supply can be effectively reduced and continuous heat supply can be realized.

Description

Technical Field

[0001] This application relates to the field of heat pump technology, and more particularly to a heat energy supply system. Background Technology

[0002] Heat pumps are recognized as a highly efficient and energy-saving technology, with significantly better operating efficiency than traditional boilers and electric water heaters. However, in practical applications, waste heat source heat pump water heating and steam systems are limited by the large temperature fluctuations, strong intermittency, and limited waste heat capacity of waste heat, making them unable to directly replace traditional boilers. Air source heat pumps, as a clean and inexhaustible renewable energy source, have provided ample room for the development of heat pump technology. However, current mainstream air source heat pump water heating and steam supply units still have functional shortcomings. Affected by the intermittent defrosting characteristics of the outdoor evaporator, the heat exchange efficiency of the unit is prone to fluctuation in low-temperature winter environments, thus failing to guarantee continuous and stable heat output, which greatly limits its application in cold regions and high-demand scenarios.

[0003] How to solve the problems of high energy consumption and high waste heat of traditional boilers and electric water heaters, while promoting the transformation of industrial heating towards electrification to adapt to the "dual carbon" strategy, the construction of zero-carbon industrial parks and the demand for green electricity consumption, and in this process, overcome the shortcomings of heat pump technology in waste heat adaptation, stable heating in winter and industrial heat recovery, and optimize the use of off-peak electricity by utilizing the time characteristics of electricity prices to reduce heating costs, are the core issues that urgently need to be solved in the technological development and application of industrial heating. Utility Model Content

[0004] One objective of this application is to provide a thermal energy supply system that can solve at least one of the defects in the aforementioned background technology.

[0005] To achieve at least one of the above objectives, the technical solution adopted in this application is as follows: a heat energy supply system, comprising an air source heat pump unit and a water storage mechanism, and further comprising a water source high-temperature heat pump; the air source heat pump unit comprises a variable frequency refrigeration compressor, a first condenser and an air-cooled evaporator, the first condenser being connected to the outlet of the variable frequency refrigeration compressor, and the air-cooled evaporator being connected to the inlet of the variable frequency refrigeration compressor; the water source high-temperature heat pump comprises a water-cooled evaporator, a variable frequency heat pump compressor, a second condenser and a third expansion valve, the outlet of the variable frequency heat pump compressor being connected to the third expansion valve via the second condenser, and the outlet of the third expansion valve being connected to the inlet of the variable frequency heat pump compressor via a pipeline connected to the water-cooled evaporator; it further comprises a heat recovery heat exchanger and a solar collector, and the water storage mechanism comprises a... The system includes a medium-temperature hot water storage tank and a high-temperature hot water storage tank. The medium-temperature hot water storage tank is connected to a first water pump and a second water pump. The outlet of the first water pump is divided into three paths: one path connects to the first condenser via a sixth solenoid valve, another path connects to the heat recovery heat exchanger via a seventh solenoid valve, and the third path connects to the solar collector via an eighth solenoid valve. The outlet of the second water pump is divided into two paths: one path supplies hot water externally via a ninth solenoid valve, and the other path connects to the inlet of a water-cooled evaporator via a pipeline. The outlet of the water-cooled evaporator is connected to the medium-temperature hot water storage tank via a pipeline. The inlet of the high-temperature hot water storage tank is connected to the second condenser. The outlet of the high-temperature hot water storage tank is divided into two paths: one path supplies hot water externally via a tenth solenoid valve, and the other path connects to the inlet of a flash evaporator via a second regulating valve. The flash evaporator is connected to a gas-liquid separator for separating steam.

[0006] Preferably, the air source heat pump unit further includes an economizer, a first expansion valve, and a second expansion valve; a first solenoid valve is provided between the first condenser and the variable frequency refrigeration compressor, and a second solenoid valve is provided between the air-cooled evaporator and the variable frequency refrigeration compressor; the outlet of the first condenser is divided into two paths, one of which is connected to the third solenoid valve through a pipeline, and the other is connected to the inlet of the second expansion valve through the fourth solenoid valve; the outlet of the third solenoid valve is connected to the second expansion valve through one of the channels of the economizer, and the other is connected to the intermediate gas injection port of the variable frequency refrigeration compressor through the first expansion valve, the other channel of the economizer, and the fifth solenoid valve.

[0007] Preferably, it also includes a water supply tank, which is provided with a water supply inlet, a water return inlet, and a water outlet. The water supply inlet is connected to the hot water pipeline where the outlets of the first condenser, the heat recovery heat exchanger, and the solar collector converge via a first regulating valve. The hot water outlet of the flash evaporator is connected to the water return inlet of the water supply tank via a pipeline. The steam outlet of the flash evaporator is connected to the gas-liquid separator. The steam outlet of the gas-liquid separator is connected to the inlet of the steam compressor. The outlet of the steam compressor is connected to the steam supply pipeline. The water outlet is connected to the high-temperature hot water storage tank via a third water pump and a second condenser.

[0008] Preferably, the water replenishment tank is equipped with a fourth temperature controller and a second liquid level controller; the fourth temperature controller and the second liquid level controller are connected to the first regulating valve through a signal line; the top of the flash evaporator is equipped with a pressure controller, which is connected to the second regulating valve through a signal line.

[0009] Preferably, a first temperature controller is provided on one inlet pipe of the first condenser, and the temperature controller is connected to the variable frequency refrigeration compressor via a signal line; a second temperature controller is provided on the outlet pipe of the second condenser, and the second temperature controller is connected to the variable frequency heat pump compressor via a signal line.

[0010] Preferably, the medium-temperature hot water storage tank is equipped with a first liquid level controller, and the lower middle part of the medium-temperature hot water storage tank is equipped with a third temperature controller; the first liquid level controller is connected to a three-way regulating valve through a signal line, and the third temperature controller is connected to a first water pump through a signal line.

[0011] This application also provides a control method for a heat energy supply system, including the following control method: Methods for preparing medium-temperature hot water; When the water temperature in the medium-temperature hot water storage tank is lower than the lower limit temperature set by the third temperature controller, the first water pump starts and pumps water out. The pumped water is heated by the first condenser, the heat recovery heat exchanger and the solar collector before returning to the medium-temperature hot water storage tank. When the water temperature reaches the upper limit temperature set by the third temperature controller, the first water pump stops working. Methods for preparing high-temperature hot water and steam; When high-temperature hot water needs to be prepared, the second water pump, the variable frequency heat pump compressor, and the third water pump are started. The hot water in the medium-temperature hot water storage tank is pumped into the water-cooled evaporator to be used as a heat source. Then, the refrigerant in the water-cooled evaporator absorbs heat and cools down before returning to the medium-temperature hot water storage tank. The water in the makeup water tank is pumped into the second condenser by the third water pump to absorb the heat from the high-temperature refrigerant after compression by the variable frequency heat pump compressor and then enters the high-temperature hot water storage tank. When steam supply is required, the second regulating valve opens and the steam compressor starts simultaneously. High-temperature hot water enters the flash evaporator and is flashed to obtain low-pressure steam. After being separated into droplets by the gas-liquid separator, the steam compressor compresses the steam to the target pressure and temperature. The unevaporated water returns to the water supply tank from the bottom outlet of the flash evaporator and is then circulated for heating and reuse.

[0012] Furthermore, the system also includes a water replenishment method. The opening of the first regulating valve is jointly controlled by the fourth temperature controller and the second liquid level controller. The liquid level is within the lower and upper limits set by the second liquid level controller. The opening of the first regulating valve is controlled by the fourth temperature controller. The higher the temperature, the larger the valve opening. When the temperature reaches the set temperature of the fourth temperature controller, the first regulating valve closes. When the liquid level is lower than the lower limit set by the second liquid level controller, the first regulating valve is forcibly opened to its maximum opening to replenish the liquid. When the liquid level is higher than the upper limit set by the second liquid level controller, the first regulating valve is forcibly closed to stop replenishing the liquid and to trigger an alarm.

[0013] Furthermore, the operating frequency of the variable frequency refrigeration compressor is controlled by the first temperature controller; when the water temperature decreases, the operating frequency of the variable frequency refrigeration compressor increases. The operating frequency of the variable frequency heat pump compressor is controlled by the water temperature at the outlet of the second condenser; when the water temperature increases, the frequency decreases.

[0014] Furthermore, when the operating frequency or flow rate of the steam compressor changes, the pressure controller at the top of the flash evaporator controls the opening of the second regulating valve to regulate the flow rate of high-temperature hot water entering the flash evaporator; when the pressure inside the flash evaporator is higher than the set pressure of the pressure controller, the pressure controller controls the second regulating valve to reduce the opening; when the pressure inside the flash evaporator is lower than atmospheric pressure, the system issues a negative pressure alarm and delays shutdown.

[0015] Compared with the prior art, the beneficial effects of this application are as follows: By coupling air-source heat pumps and water-source heat pumps with industrial heat recovery and solar collectors, medium-temperature and high-temperature hot water supply can be achieved simultaneously. The high-temperature hot water can be compressed into high-temperature steam through flash vaporization to meet the heating needs of different industrial production processes. The combined use of medium-temperature and high-temperature hot water storage tanks can effectively reduce heating fluctuations and ensure continuous heating during periods of low temperature, unaffected by the defrosting process of the air-source heat pump.

[0016] Air source heat pump units can determine their operating mode based on whether it is during green electricity periods. By switching between modes with and without the economizer, they can adapt to the differences in summer and winter operating conditions while ensuring the supply of medium-temperature hot water, thereby improving the operating energy efficiency of air source heat pump units. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the heat supply system in this application.

[0018] In the diagram: 10. Flash evaporator; 11. Water tank; 12. Third water pump; 13. Gas-liquid separator; 14. Steam compressor; 15. Third temperature controller; 16. First liquid level controller; 17. First temperature controller; 18. Fourth temperature controller; 19. Second liquid level controller; 101. Variable frequency refrigeration compressor; 102. First condenser; 103. Economizer; 104. First expansion valve; 105. Second expansion valve; 106. Air-cooled evaporator; 107. First solenoid valve; 108. Second solenoid valve; 109. Third solenoid valve; 110. Fourth solenoid valve. 1. Solenoid valve; 2. Medium-temperature hot water storage tank; 3. Pressure controller; 4. Second temperature controller; 5. First regulating valve; 6. Second regulating valve; 7. Sixth solenoid valve; 8. Seventh solenoid valve; 9. Eighth solenoid valve; 10. Ninth solenoid valve; 11. Tenth solenoid valve; 12. Three-way regulating valve; 13. First water pump; 14. Heat recovery heat exchanger; 15. Solar collector; 16. Second water pump; 17. Water-cooled evaporator; 18. Variable frequency heat pump compressor; 19. Second condenser; 20. Third expansion valve; 21. High-temperature hot water storage tank. Detailed Implementation

[0019] The present application will be further described below with reference to specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0020] In the description of this application, it should be noted that the terms "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., which indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and should not be construed as limiting the specific protection scope of this application.

[0021] It should be noted that the terms "first," "second," etc., in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0022] The terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0023] One aspect of this application provides a heat supply system, one preferred embodiment of which is, for example... Figure 1 As shown, the system includes an air-source heat pump unit, a water storage mechanism, and a water-source high-temperature heat pump. The air-source heat pump unit includes a variable frequency refrigeration compressor 101, a first condenser 102, and an air-cooled evaporator 106. The first condenser 106 is connected to the outlet of the variable frequency refrigeration compressor 101, and the air-cooled evaporator 106 is connected to the inlet of the variable frequency refrigeration compressor 101. The water-source high-temperature heat pump includes a water-cooled evaporator 801, a variable frequency heat pump compressor 802, a second condenser 803, and a third expansion valve 804. The outlet of the variable frequency heat pump compressor 802 is connected to the third expansion valve 804 via the second condenser 803, and the outlet of the third expansion valve 804 is connected to the inlet of the variable frequency heat pump compressor 802 via a pipeline. The liquid in the pipeline is heated by the air-source heat pump unit and the water-source high-temperature heat pump, and the heated water is stored in the water storage mechanism.

[0024] Specifically, the air source heat pump unit also includes an economizer 103, a first expansion valve 104, and a second expansion valve 105. The outlet of the variable frequency refrigeration compressor 101 is divided into two paths: one path connects to the a1 inlet of the first condenser 102 via the first solenoid valve 107, and the other path connects to the inlet of the air-cooled evaporator 106 via the second solenoid valve 108. The a2 outlet of the first condenser 102 is divided into two paths: one path connects to the third solenoid valve 109 via a pipeline, and the other path connects to the inlet of the second expansion valve 105 via the fourth solenoid valve 110. One path of the outlet of the third solenoid valve 109 connects to the second expansion valve 105 via the b1 inlet and b3 outlet of the economizer 103, and the other path connects to the intermediate gas injection port of the variable frequency refrigeration compressor 101 via the first expansion valve 104, the b2 inlet and b4 outlet of the economizer 103, and the fifth solenoid valve 111.

[0025] In this embodiment, the air source heat pump unit has the following two operating modes.

[0026] The first method: Without starting the economizer 103, the third solenoid valve 109 and the fifth solenoid valve 111 are closed, and the fourth solenoid valve 110 is open; the refrigerant liquid in the first condenser 102 enters the air-cooled evaporator 106 through the second expansion valve 105 and absorbs heat from the air, evaporating into low-pressure gas; then the low-pressure gas is compressed into high-temperature, high-pressure gas by the variable frequency refrigeration compressor 101 and returns to the first condenser 102. In the first condenser 102, the high-temperature, high-pressure gas transfers heat to the internal air or water, while the high-temperature, high-pressure gas itself is condensed into liquid in preparation for the next stage of heating.

[0027] The second method: When the economizer 103 is activated, the third solenoid valve 109 and the fifth solenoid valve 111 open, and the fourth solenoid valve 110 closes. The liquid refrigerant in the first condenser 102 flows out through two paths. One path involves entering the heat exchange tube of the economizer 103 through the first expansion valve 104, absorbing heat and evaporating into a medium-pressure gas, which then enters the variable frequency refrigeration compressor 101 through the central air injection port. The other path involves entering another heat exchange tube of the economizer 103, releasing heat and increasing its cooling temperature, then entering the air-cooled evaporator 106 through the second expansion valve 105, evaporating into a low-pressure gas, and then entering the variable frequency refrigeration compressor 101. The high-temperature, high-pressure gases generated by both paths will enter the first condenser 102 to release heat.

[0028] Understandably, both heating modes described above can meet the heating requirements. However, air source heat pump units are quite sensitive to ambient temperature. Due to significant seasonal differences in ambient air temperature, summer ambient temperatures can reach as high as 35℃, while winter ambient temperatures can drop as low as -10℃. The economizer 103 is an effective method for ensuring the heating capacity of the air source heat pump unit under low ambient air temperatures; however, during summer operation, the economizer 103 does not need to operate. Therefore, the system uses a solenoid valve design to allow the refrigerant in the first condenser 102 to selectively enter the economizer 103.

[0029] It should be noted that when the ambient temperature is low in winter, frost will form on the surface of the evaporator. Considering the simplicity of the system, this utility model adopts a hot gas bypass dehumidification method. When the air-cooled evaporator 106 needs to be defrosted, the first solenoid valve 107 is closed and the second solenoid valve 108 is opened. The high-temperature refrigerant compressed by the variable frequency refrigeration compressor 101 enters the air-cooled evaporator 106 to release heat and melt the frost on the outside of the pipe.

[0030] In this embodiment, as Figure 1As shown, the heat supply system also includes a heat recovery heat exchanger 5, a first water pump 4, a second water pump 7, and a solar collector 6. The water storage mechanism includes a medium-temperature hot water storage tank 2 and a high-temperature hot water storage tank 9. The medium-temperature hot water storage tank 2 has interfaces d2, d1, d3, and d4 from top to bottom. Interface d4 is connected to the first inlet of a three-way regulating valve 3, and the second inlet of the three-way regulating valve 3 is connected to the water supply pipeline. The outlet of the three-way regulating valve 3 is connected to the first water pump 4. The outlet of the first water pump 4 is divided into three paths: one path is connected to the a3 inlet of the first condenser 102 via the sixth solenoid valve 24; another path is connected to the c1 inlet of the heat recovery heat exchanger 5 via the seventh solenoid valve 25; and the third path is connected to the j1 inlet of the solar collector 6 via the eighth solenoid valve 26. The a4 outlet of the first condenser 102, the c2 outlet of the heat recovery heat exchanger 5, and the j2 outlet of the solar collector 6 are connected to the d1 interface of the medium-temperature hot water storage tank 2 via pipelines. The liquid in the water supply pipeline can be heated by three heating devices: the first condenser 102, the heat recovery heat exchanger 5, and the solar collector 6. The liquid heated by the three devices flows into the medium-temperature hot water storage tank for storage.

[0031] Furthermore, the D2 interface of the medium-temperature hot water storage tank 2 is connected to the second water pump 7. One outlet of the second water pump 7 supplies hot water externally via the ninth solenoid valve 27, and the other outlet is connected via a pipeline to the J4 inlet of the water-cooled evaporator 801. The J3 outlet of the water-cooled evaporator 801 is connected via a pipeline to the D3 interface of the medium-temperature hot water storage tank 2. The hot water preparation system uses a circulating heating method, which ensures that the medium-temperature hot water temperature meets the requirements of the high-temperature heat pump operation, thereby reducing the energy loss caused by prolonged partial operation of the system due to the maximum load design of a traditional single unit.

[0032] In this embodiment, as Figure 1 As shown, the heat supply system also includes a water supply tank 11, which has a water inlet e1, a return water inlet e2, and a water outlet e3. The water inlet e1 is connected to the hot water pipeline where the outlets of the first condenser 102, the heat recovery heat exchanger 5, and the solar collector 6 converge via a first regulating valve 22. The water outlet e3 is connected to the g1 interface of the high-temperature hot water storage tank 9 via a third water pump 12, the f1 inlet of the second condenser 803, and the f2 outlet of the high-temperature hot water storage tank 9. The g1 interface of the high-temperature hot water storage tank 9 is connected to the second condenser 803. The g2 outlet of the high-temperature hot water storage tank 9 supplies hot water to the outside via a tenth solenoid valve 28. The g3 outlet of the high-temperature hot water storage tank 9 is connected to the h1 inlet of the flash evaporator 10 via a second regulating valve 23. The flash evaporator 10 is connected to a gas-liquid separator 13 for separating steam.

[0033] Specifically, the hot water outlet h3 of the flash evaporator 10 is connected to the return water outlet e2 of the water supply tank 11 via a pipeline; the steam outlet h2 of the flash evaporator 10 is connected to the gas-liquid separator 13; the steam outlet i2 of the gas-liquid separator 13 is connected to the inlet of the steam compressor 14; and the outlet of the steam compressor 14 is connected to the steam supply pipeline.

[0034] Understandably, when the steam compressor 14 starts, high-temperature hot water enters the flash evaporator 10 and is flashed to obtain low-pressure steam. The low-pressure steam is separated into droplets by the gas-liquid separator 13 and then enters the steam compressor 14 to be compressed to the target pressure and temperature. The water that is not evaporated returns to the water tank 11 from the bottom outlet h3 of the flash evaporator 10 and continues to be circulated and heated for use.

[0035] It should be noted that the steam supply unit and the water source high-temperature heat pump water heater in this application are operated and controlled independently, which can make reasonable use of the price advantages of off-peak electricity and green electricity to efficiently store heat during the off-peak period of heat demand.

[0036] In this embodiment, as Figure 1 As shown, the water replenishment tank 11 is equipped with a fourth temperature controller 18 and a second liquid level controller 19, which are connected to the first regulating valve 22 via signal lines. The flash evaporator 10 has a pressure controller 20 on top, which is connected to the second regulating valve 23 via a signal line. When the liquid level in the water replenishment tank 11 is within the lower and upper limits set by the second liquid level controller 19, the fourth temperature controller 18 controls the opening of the first regulating valve 22; the higher the temperature, the larger the opening of the first regulating valve 22. When the temperature reaches the set temperature of the fourth temperature controller 18, the first regulating valve 22 closes, thus ensuring the stability of the high-temperature heat pump's operation. When the liquid level is lower than the lower limit set by the second liquid level controller 19, the first regulating valve 22 is forcibly opened to its maximum opening for replenishment; when the liquid level is higher than the upper limit set by the second liquid level controller 19, the first regulating valve 22 is forcibly closed to stop replenishment and trigger an alarm. This allows for automatic adjustment based on the liquid level in the water replenishment tank 11, further improving the operational stability of the water replenishment tank 11.

[0037] Furthermore, such as Figure 1 As shown, a first temperature controller 17 is installed on the pipe near the a3 inlet of the first condenser 102, and the first temperature controller 17 is connected to the variable frequency refrigeration compressor 101 via a signal line; a second temperature controller 21 is installed on the pipe located at the f2 outlet of the second condenser 803, and the second temperature controller 21 is connected to the variable frequency heat pump compressor 802 via a signal line. The first temperature controller 17 can control the operating frequency of the variable frequency refrigeration compressor 101; the lower the water temperature, the higher the operating frequency of the variable frequency refrigeration compressor 101. The second temperature controller 21 can control the operating frequency of the variable frequency heat pump compressor 802; the lower the water temperature, the higher the operating frequency of the variable frequency heat pump compressor 802.

[0038] In this embodiment, as Figure 1As shown, the medium-temperature hot water storage tank 2 is equipped with a first liquid level controller 16, and a third temperature controller 15 is installed in the lower middle part of the medium-temperature hot water storage tank 2; the first liquid level controller 16 is connected to the three-way regulating valve 3 through a signal line, and the third temperature controller 15 is connected to the first water pump 4 through a signal line.

[0039] Specifically, the first liquid level controller 16 is used to control the opening of the three-way regulating valve 3 so that the water in the medium-temperature hot water storage tank 2 enters the first water pump 4. The lower the liquid level in the medium-temperature hot water storage tank 2, the smaller the opening of the three-way regulating valve 3, and at the same time, the flow rate of the replenishment water entering the three-way regulating valve 3 increases.

[0040] Specifically, the third temperature controller 15 is used to control the opening of the first water pump 4. When the water temperature in the medium-temperature hot water storage tank 2 is lower than the lower limit temperature set by the third temperature controller 15, the first water pump 4 runs to pump water out and deliver it to the heating equipment (first condenser 102, heat recovery heat exchanger 5 and solar collector 6) for heating. When the water temperature reaches the upper limit temperature set by the third temperature controller 15, the first water pump 4 stops working.

[0041] This application also provides a control method for a heat energy supply system, including the following control method.

[0042] Method for preparing medium-temperature hot water.

[0043] When the water temperature in the medium-temperature hot water storage tank 2 is lower than the lower limit temperature set by the third temperature controller 15, the first water pump 4 starts and pumps water out. The pumped water is heated by the first condenser 102, the heat recovery heat exchanger 5, and the solar collector 6 before returning to the medium-temperature hot water storage tank 2. When the water temperature reaches the upper limit temperature set by the third temperature controller 15, the first water pump 4 stops working. During heating, the sixth solenoid valve 24 and the seventh solenoid valve 25 should be opened first to heat the water pumped out by the first water pump 4 using the heat recovery heat exchanger 5 and the solar collector 6. When the waste heat energy and solar energy supply are insufficient or unavailable, the variable frequency refrigeration compressor 101 is started, and the first condenser 102 of the air source heat pump unit is used to complete the water heating.

[0044] Methods for preparing high-temperature hot water and steam.

[0045] When high-temperature hot water needs to be prepared, the second water pump 7, the variable frequency heat pump compressor 802, and the third water pump 12 are started. The hot water in the medium-temperature hot water storage tank 2 is pumped into the water-cooled evaporator 801 and used as a heat source. Then, the water is cooled down by the refrigerant in the water-cooled evaporator 801 and then returned to the medium-temperature hot water storage tank 2. The water in the makeup water tank 11 is pumped into the second condenser 803 by the third water pump 12 to absorb the heat of the high-temperature refrigerant after compression by the variable frequency heat pump compressor 802 and then enters the high-temperature hot water storage tank 9.

[0046] When steam supply is required, the second regulating valve 23 opens, and the steam compressor 14 starts simultaneously. High-temperature hot water enters the flash evaporator 10 and is flash-evaporated to obtain low-pressure steam. After being separated into droplets by the gas-liquid separator 13, the steam compressor 14 compresses the steam to the target pressure and temperature. The unevaporated water returns to the water supply tank 11 through the bottom outlet h3 of the flash evaporator 10 and continues to be circulated and heated. When the operating frequency or flow rate of the steam compressor 14 changes, the pressure controller 20 at the top of the flash evaporator 10 controls the opening of the second regulating valve 23 to regulate the flow rate of high-temperature hot water entering the flash evaporator 10. When the pressure inside the flash evaporator 10 is higher than the set pressure of the pressure controller 20, the pressure controller 20 controls the second regulating valve 23 to reduce its opening. When the pressure inside the flash evaporator 10 is lower than atmospheric pressure, the system issues a negative pressure alarm and delays shutdown.

[0047] To further reduce the operating costs of this device, air-source heat pump units and water-source high-temperature heat pumps can be driven during off-peak electricity periods to produce hot water for heat storage, ensuring the system's economic operation when solar energy is unavailable. Specifically, when the device operates during off-peak electricity periods, even if the water temperature in the medium-temperature hot water storage tank 2 has not reached the set lower limit, the first water pump 4 and the variable frequency refrigeration compressor 101 are started. The air-source heat pump unit is driven by off-peak electricity to heat the water in the hot water storage tank to the set upper limit, thus achieving off-peak electricity energy storage. During off-peak electricity periods, high-temperature hot water is continuously produced preferentially by the water-source high-temperature heat pump until the high-temperature hot water in the high-temperature hot water storage tank 9 reaches the maximum liquid level.

[0048] Furthermore, it also includes water replenishment control methods and air source heat pump unit control methods.

[0049] Specifically, the water replenishment control method is as follows: the liquid level controller 16 in the medium-temperature hot water storage tank 2 controls the three-way regulating valve 3 to adjust the ratio of low-temperature replenishment water pumped into the first water pump 4 to hot water flowing out of the medium-temperature hot water storage tank 2. The lower the liquid level, the higher the proportion of replenishment water. Part of the heated medium-temperature hot water enters the medium-temperature hot water storage tank 2, and the other part enters the replenishment tank 11 after the flow rate is regulated by the first regulating valve 22. The opening of the first regulating valve 22 is jointly controlled by the fourth temperature controller 18 and the second liquid level controller 19. The liquid level is within the lower and upper limits set by the second liquid level controller 19. The opening of the first regulating valve 22 is controlled by the fourth temperature controller 18. The higher the temperature, the larger the valve opening. When the temperature reaches the set temperature of the fourth temperature controller 18, the first regulating valve 22 closes; when the liquid level is lower than the lower limit set by the second liquid level controller 19, the first regulating valve 22 is forcibly opened to its maximum opening for replenishment. When the liquid level is higher than the upper limit set by the second liquid level controller 19, the first regulating valve 22 is forcibly closed to stop the liquid replenishment and to trigger an alarm.

[0050] Specifically, the control method for the air source heat pump unit is as follows: When the heat supply system is operating normally, the first solenoid valve 107 is open and the second solenoid valve 108 is closed; when the ambient temperature is higher than a certain set value, the third solenoid valve 109 and the fifth solenoid valve 111 are closed, the economizer 103 does not work, and the fourth solenoid valve 110 is open. At this time, the refrigerant liquid flowing out of the outlet a2 of the first condenser 102 enters the air-cooled evaporator 106 through the second expansion valve 105, absorbs heat from the environment to evaporate, and then returns to the first condenser 102 after being compressed by the variable frequency refrigeration compressor 101. When the ambient temperature is not higher than a certain set value, the third solenoid valve 109 and the fifth solenoid valve 111 are opened, and the fourth solenoid valve 110 is closed. The refrigerant liquid flowing out of the outlet a2 of the first condenser 102 enters the heat exchange tube of the economizer 103 through the first expansion valve 104 to absorb heat and evaporate. Then it enters the gas injection port of the variable frequency refrigeration compressor 101 through the fifth solenoid valve 111. Another path enters another heat exchange tube of the economizer 103 to release heat and increase the subcooling. Then it enters the air-cooled evaporator 106 through the second expansion valve 105 to absorb heat from the environment and evaporate. Then it enters the variable frequency refrigeration compressor 101.

[0051] It should be noted that in the air source heat pump unit control method and the high-temperature hot water preparation method, the operating frequency of the variable frequency refrigeration compressor 101 is controlled by the first temperature controller 17; when the water temperature decreases, the operating frequency of the variable frequency refrigeration compressor 101 increases. The operating frequency of the variable frequency heat pump compressor 802 is controlled by the water temperature at the outlet f2 of the second condenser 803; when the water temperature increases, the frequency decreases. This application adopts a feedforward control method, that is, controlling the operating frequency of the variable frequency refrigeration compressor 101 according to the inlet water temperature of the first condenser 102, reducing the temperature fluctuation of the medium-temperature hot water storage tank 2, and ensuring the stability of the high-temperature water source heat pump operation.

[0052] The basic principles, main features, and advantages of this application have been described above. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely the principles of this application. Various changes and modifications can be made to this application without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection claimed by this application is defined by the appended claims and their equivalents.

Claims

1. A heat energy supply system, comprising an air source heat pump unit and a water storage mechanism, characterized in that, It is also equipped with a water source high-temperature heat pump; the air source heat pump unit includes a variable frequency refrigeration compressor (101), a first condenser (102) and an air-cooled evaporator (106), the first condenser (102) is connected to the outlet of the variable frequency refrigeration compressor (101), and the air-cooled evaporator (106) is connected to the inlet of the variable frequency refrigeration compressor (101); The water source high-temperature heat pump includes a water-cooled evaporator (801), a variable frequency heat pump compressor (802), a second condenser (803), and a third expansion valve (804). The outlet of the variable frequency heat pump compressor (802) is connected to the third expansion valve (804) via the second condenser (803). The outlet of the third expansion valve (804) is connected to the inlet of the variable frequency heat pump compressor (802) via a pipeline and the water-cooled evaporator (801). The water storage mechanism includes a medium-temperature hot water storage tank (2) and a high-temperature hot water storage tank (9); the medium-temperature hot water storage tank (2) is connected to a first water pump (4) and a second water pump (7), the first water pump (4) is connected to the first condenser (102) via a sixth solenoid valve (24); the outlet of the second water pump (7) is divided into two paths, one path supplies hot water to the outside via a ninth solenoid valve (27), and the other path is connected to the inlet of a water-cooled evaporator (801) via a pipeline, the outlet of the water-cooled evaporator (801) is connected to the medium-temperature hot water storage tank (2) via a pipeline; the inlet of the high-temperature hot water storage tank (9) is connected to the second condenser (803), one outlet of the high-temperature hot water storage tank (9) is connected to the inlet of a flash evaporator (10) via a second regulating valve (23), and the flash evaporator (10) is connected to a gas-liquid separator (13) for separating steam.

2. The heat energy supply system as described in claim 1, characterized in that, It also includes a heat recovery heat exchanger (5) and a solar collector (6). The first water pump (4) is also provided with two other outlets, one of which is connected to the heat recovery heat exchanger (5) via a seventh solenoid valve (25), and the other outlet is connected to the solar collector (6) via an eighth solenoid valve (26).

3. The heat supply system as described in claim 1, characterized in that, One outlet of the high-temperature hot water storage tank (9) supplies hot water to the outside via the tenth solenoid valve (28).

4. The heat energy supply system as described in claim 1, characterized in that, A first solenoid valve (107) is provided between the first condenser (102) and the variable frequency refrigeration compressor (101), and a second solenoid valve (108) is provided between the air-cooled evaporator (106) and the variable frequency refrigeration compressor (101).

5. The heat supply system as described in claim 1, characterized in that, The air source heat pump unit also includes an economizer (103), a first expansion valve (104), and a second expansion valve (105); the outlet of the first condenser (102) is divided into two paths, one of which is connected to the third solenoid valve (109) through a pipeline, and the other is connected to the inlet of the second expansion valve (105) through the fourth solenoid valve (110); the outlet of the third solenoid valve (109) is connected to the second expansion valve (105) through one of the channels of the economizer (103), and the other is connected to the intermediate gas inlet of the variable frequency refrigeration compressor (101) through the first expansion valve (104), the other channel of the economizer (103), and the fifth solenoid valve (111).

6. The heat supply system as described in claim 1, characterized in that, It also includes a water supply tank (11), which is provided with a water supply port and a water outlet. The water supply port is connected to the hot water pipeline after the outlets of the first condenser (102), the heat recovery heat exchanger (5) and the solar collector (6) are combined via the first regulating valve (22); the water outlet is connected to the high temperature hot water storage tank (9) via the third water pump (12) and the second condenser (803).

7. The heat supply system as described in claim 6, characterized in that, The water supply tank is also provided with a return water port. The hot water outlet of the flash evaporator (10) is connected to the return water port of the water supply tank (11) via a pipeline. The steam outlet of the flash evaporator (10) is connected to the gas-liquid separator (13). The steam outlet of the gas-liquid separator (13) is connected to the inlet of the steam compressor (14). The outlet of the steam compressor (14) is connected to the steam supply pipeline.

8. The heat supply system as described in claim 6, characterized in that, The water supply tank (11) is equipped with a fourth temperature controller (18) and a second liquid level controller (19); the fourth temperature controller (18) and the second liquid level controller (19) are connected to the first regulating valve (22) through a signal line; the flash evaporator (10) is equipped with a pressure controller (20) on top, and the pressure controller (20) is connected to the second regulating valve (23) through a signal line.

9. The heat energy supply system as described in claim 1, characterized in that, The first condenser (102) is provided with a first temperature controller (17) on its inlet pipe, and the temperature controller is connected to the variable frequency refrigeration compressor (101) via a signal line; the second condenser (803) is provided with a second temperature controller (21) on its outlet pipe, and the second temperature controller (21) is connected to the variable frequency heat pump compressor (802) via a signal line.

10. The heat energy supply system as described in claim 1, characterized in that, The medium-temperature hot water storage tank (2) is equipped with a first liquid level controller (16), and a third temperature controller (15) is installed in the lower middle part of the medium-temperature hot water storage tank (2); the first liquid level controller (16) is connected to a three-way regulating valve (3) through a signal line, and the third temperature controller (15) is connected to a first water pump (4) through a signal line.

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