A solar coupled heat pump combined cooling, heating and power system and its working method

Abstract

The present invention discloses a solar-coupled heat pump combined heat and power (CCHP) system and its operating method. The power generation and consumption system of the CCHP system includes a PVT component, an inverter, a power grid, and a user end within a building. The inverter is respectively connected to the circuits of the power grid and the user end. The heat generation, heat storage, and heat consumption system includes a heat collection tank, a domestic hot water tank, a heat exchanger, a water-source heat pump, and an air-water heat exchanger. The heat exchanger is connected to a cold water inlet and a hot water demand end, and the cold water inlet and the hot water demand end are respectively connected to the water pipes at the user end. The cooling, cold storage, and cold consumption system includes a cold water tank and a fan coil unit, and the fan coil unit supplies cold water to the user end. The operating method includes a power supply mode, a heating mode, and a cooling mode. The present invention adopts the key technologies of the PVT-coupled heat pump and a modular control strategy to realize the intelligent combination of solar energy and electric energy, giving the system the function of combined heat, cooling, and power. It is an effective way to improve the comprehensive utilization rate of solar energy and achieve energy conservation and emission reduction in buildings.

Description

Technical Field

[0001] The present invention belongs to the field of new energy utilizing solar energy, and in particular relates to a solar-coupled heat pump combined cooling, heating and power system and a working method thereof. Background Art

[0002] Solar photovoltaic power generation is one of the most widely used active building energy-saving technologies. However, existing solar cells convert only 15% to 20% of incoming solar radiation into electricity. The majority of this radiation is converted into heat, causing the operating temperature of the photovoltaic panels to reach over 80°C. Furthermore, with every 1°C increase in temperature, the output power of the photovoltaic panels decreases by 0.4% to 0.5%. Excessive temperatures also reduce the service life of the solar cells. To address this issue, flow channels can be laid on the back of the solar cells to remove heat through a heat-collecting medium and transfer it to a heat pump or electric heater for conversion into high-quality thermal energy. This system, which generates both electricity and heat, is called a photovoltaic-thermal integrated system (PVT system). Theoretically, the comprehensive utilization rate of solar energy can be increased to over 80%, making it the most efficient technology currently available. PVT modules are often used in conjunction with heat pump systems to improve thermal energy utilization. However, traditional PVT heat pump coupling systems still face the following technical bottlenecks:

[0003] (1) Among the installed PVT systems, more than 90% are heating and hot water systems. There is no construction and operation of cooling and hot water combined supply systems. The existing PVT heat pump coupling technology cannot meet the high cooling demand of buildings;

[0004] (2) PVT modules usually use water or antifreeze as the heat collection medium, absorbing heat through the temperature change of water (sensible heat capacity). The heat transfer efficiency is low, and the heat collection efficiency is only 10% to 35%.

[0005] Patent application number 201710628772.3 discloses "a solar photovoltaic combined cooling, heating and power composite energy system", which has the following shortcomings: First, phase change energy storage material is used behind the solar panel. Due to the solid-liquid transition of the material, it cannot be directly used as a heat collection medium, and another fluid (tap water is used here) is required to take away the heat stored in the phase change material. Since the thermal conductivity of most phase change materials, especially organic phase change materials, is very low, generally only 0.2W / (m·k), the heat transfer efficiency is poor; second, the solar photovoltaic thermal component is connected to the heat pump through a heat exchanger. The heat of the component is only stored in the phase change material on the back of the component. The energy storage capacity is small, and the component is prone to overheating under high temperature conditions in summer. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a solar-coupled heat pump combined heating, cooling and power system and its working method in response to the shortcomings of the existing technology, which realizes the intelligent combination of solar energy and electric energy, and gives the system the function of trigeneration of heating, cooling and power. It is an effective way to improve the comprehensive utilization rate of solar energy and achieve energy conservation and emission reduction in buildings.

[0007] The technical solution adopted by the present invention to solve the above technical problems is: a solar coupled heat pump combined heat and power system, which includes a power generation-power consumption system, a heat generation-heat storage-heat consumption system and a refrigeration-cold storage-cold consumption system; the power generation-power consumption system includes a PVT component, an inverter, a power grid and a user end in a building, the positive and negative power generation poles of the photovoltaic panel on the front of the PVT component are connected to the inverter, and the inverter is respectively connected to the power grid and the circuit of the user end; the heat generation-heat storage-heat consumption system includes a heat collection tank, a domestic hot water tank, a heat exchanger, a water-water source heat pump and an air-water heat exchanger, the heat collection tank is provided with an internal coil, the back heat dissipation component of the PVT component is connected to the internal coil via a pipeline to form a first circuit, the first circuit has a phase change fluid built in, and the upper layer of the heat collection tank is connected to the bottom of the domestic hot water tank The water outlet is connected, the top water outlet of the domestic hot water tank is connected to a return water pipeline, the return water pipeline is connected to the bottom water inlet of the heat collecting tank through the heat exchanger, the heat exchanger is connected to a cold water outlet and a hot water demand end, the cold water outlet and the hot water demand end are respectively connected to the water pipeline of the user end, the water-water source heat pump includes a condenser and an evaporator, the condenser and the domestic hot water tank are connected to the second circuit via a pipeline, the air-water heat exchanger is connected to the evaporator via a pipeline as the third circuit, and the air-water heat exchanger is connected to the condenser via a pipeline as the fourth circuit; the refrigeration-cold storage-cold use system includes a cold water tank and a fan coil, the fan coil and the cold water tank are connected to the fifth circuit via a pipeline, the fan coil supplies cold to the user end, and the cold water tank and the evaporator are connected to the sixth circuit via a pipeline.

[0008] The PVT component in the solar-coupled heat pump combined heating and cooling power system of the present invention uses phase change fluid as the heat collection medium, and utilizes the solid-liquid phase change process of the dispersed phase of the phase change material to increase the energy storage capacity. Compared with traditional single-phase fluids such as water or antifreeze, it can effectively improve the heat collection efficiency of the PVT component; the heat of the PVT component can be quickly removed through the efficient heat transfer of the phase change fluid, and because the thermal conductivity of the phase change fluid is higher than that of the phase change material, and the heat transfer efficiency can be further increased by adjusting the flow rate, the temperature of the PVT component can be effectively controlled even under high temperature conditions in summer, thereby improving the power generation efficiency and heat collection efficiency of the PVT component.

[0009] Phase Change Slurry (PCS) is a functional two-phase fluid, which refers to an emulsion or suspension formed by uniformly dispersing phase change materials in the form of particles, microcapsules or shaped particles in a carrier fluid. The particle size of the dispersed phase of the phase change material is generally not more than 100 μm. Among them, phase change material microcapsules refer to composite phase change materials with a core-shell structure formed by coating a layer of stable performance membrane on the surface of phase change material particles; phase change material shaped particles utilize the tiny pores inside the porous medium material to adsorb phase change materials, and use the capillary effect to improve the reliability of phase change material storage in the porous medium, so that no liquid leakage occurs when solid-liquid phase change occurs. The phase change fluid used in the PVT component of the solar coupled heat pump combined heat and power system of the present invention can be one of a phase change emulsion, a phase change material microcapsule suspension or a phase change material shaped particle suspension.

[0010] The front photovoltaic panel of the PVT component of the solar-coupled heat pump combined heating, cooling and power supply system of the present invention absorbs solar energy and converts it into electrical energy and thermal energy, and supplies power to the user end first. When the power supply is in excess, the excess power is incorporated into the power grid. When the power is insufficient, the power grid is used to supplement the power to the user end, thereby reducing energy waste and achieving building energy saving; the PVT component is connected to the water-water source heat pump through a double water tank (i.e., a heat collection tank and a domestic hot water tank), and heat is stored in the two water tanks. The energy storage capacity is significantly increased, which can effectively reduce the temperature of the PVT component and provide preheating for domestic hot water at the same time; the condenser of the water-water source heat pump is coupled with the domestic hot water tank, and the water-water source heat pump is used to produce hot water when solar energy is insufficient, and the evaporator of the water-water source heat pump is coupled with the cold water tank to provide chilled water for building cooling. The excess heat can be discharged to the outside through the air-water heat exchanger.

[0011] The solar-coupled heat pump combined heating, cooling and power system of the present invention adopts the key technology of PVT-coupled heat pump and modular control strategy, realizes the intelligent combination of solar energy and electric energy, and gives the system the function of combined heating, cooling and power. It is an effective way to improve the comprehensive utilization rate of solar energy and achieve energy conservation and emission reduction in buildings.

[0012] Preferably, the front photovoltaic panel of the PVT component absorbs solar energy and converts it into electrical energy and thermal energy, and the heat absorbed by the back heat dissipation component of the PVT component is transported to the heat collection tank through the phase change fluid, and the heat collection tank and the domestic hot water tank transport domestic hot water to the hot water demand end, and when the amount of hot water is insufficient, the water-water source heat pump is started to supplement hot water to the hot water demand end.

[0013] Preferably, a No. 2 three-way valve is installed on the pipeline between the bottom water outlet of the cold water tank and the inlet end of the fan coil, and a return pipe is connected between the top water inlet of the cold water tank and the No. 2 three-way valve.

[0014] Preferably, the inverter is connected to a No. 1 controller, and the No. 1 controller is used to manage and adjust the power output of the combined heating, cooling and power system.

[0015] Preferably, a No. 1 water pump is installed on the first circuit, a first temperature sensor T1 is installed on the liquid outlet of the heat dissipation component on the back of the PVT assembly, a second temperature sensor T2 is installed on the bottom water inlet of the heat collection tank, the first temperature sensor T1 and the second temperature sensor T2 are respectively connected to the No. 2 controller, the top water outlet of the domestic hot water tank is installed with a third temperature sensor T3, the cold water outlet is installed with a fourth temperature sensor T4, the third temperature sensor T3 and the fourth temperature sensor T4 are respectively connected to the No. 3 controller. The controllers are connected, the condenser and the evaporator are connected via an expansion valve and a compressor, a No. 2 water pump is installed on the return pipe, a No. 3 water pump is installed on the second circuit, a No. 1 three-way valve and a No. 4 water pump are installed on the third circuit, and a No. 5 water pump is installed on the fourth circuit. The No. 2 controller is used to control the No. 1 water pump, the No. 3 controller is used to control the No. 2 water pump, and the No. 3 water pump, the No. 4 water pump, the No. 5 water pump, the No. 1 three-way valve and the water-water source heat pump are controlled by the No. 4 controller.

[0016] Preferably, the top water inlet and the bottom water outlet of the cold water tank are respectively installed with a fifth temperature sensor T5 and a sixth temperature sensor T6, the fifth temperature sensor T5 and the sixth temperature sensor T6 are respectively connected to the No. 4 controller, the No. 1 three-way valve and the No. 4 water pump are installed on the sixth circuit, the No. 6 water pump is installed on the pipeline between the No. 2 three-way valve and the inlet end of the fan coil, and the No. 2 three-way valve, the No. 6 water pump and the fan coil are controlled by the No. 5 controller.

[0017] A working method of the above-mentioned solar-coupled heat pump combined heating, cooling and power system includes a power supply mode, a heating mode and a cooling mode:

[0018] S1, power supply mode:

[0019] The front photovoltaic panel of the PVT module absorbs solar energy and converts it into electrical energy and thermal energy. The PVT module preferentially supplies power to the user end through the inverter and the first controller. When there is excess power supplied, the excess power is incorporated into the power grid. When there is insufficient power, the power grid is used to supplement the power supply to the user end.

[0020] S2, heating mode:

[0021] The heat absorbed by the heat dissipation component on the back of the PVT assembly is transferred to the heat collecting tank via the phase change fluid. When the temperature difference between the first temperature sensor T1 and the second temperature sensor T2 is not lower than a set value, the second controller turns on the first water pump. At this time, the first circuit is connected, the PVT assembly dissipates heat via the phase change fluid, and the heat collecting tank stores heat. When the temperature difference between the first temperature sensor T1 and the second temperature sensor T2 is lower than a set value, the second controller stops the first water pump, and the PVT assembly stops dissipating heat via the phase change fluid.

[0022] When there is no domestic hot water demand at the hot water demand end, the No. 3 controller turns off the No. 2 water pump; when there is domestic hot water demand at the hot water demand end, the water in the heat collecting tank is input into the domestic hot water tank, the No. 3 controller turns on the No. 2 water pump, and the cold water at the cold water outlet exchanges heat through the heat exchanger, so that the water temperature at the hot water demand end is raised to the temperature set value of the domestic hot water at the hot water demand end;

[0023] The water-to-water source heat pump generates hot water with a temperature of 45°C to 60°C through the condenser. When the PVT component does not collect sufficient solar radiation and the difference between the temperature of the third temperature sensor T3 and the temperature setting value of the domestic hot water at the hot water demand end is not greater than 2°C, the No. 4 controller turns on the No. 3 water pump and the water-to-water source heat pump to heat the water in the domestic hot water tank to a temperature that is more than 2°C higher than the temperature setting value of the domestic hot water at the hot water demand end. At this time, the second circuit and the third circuit are connected. When the difference between the temperature of the third temperature sensor T3 and the temperature setting value of the domestic hot water at the hot water demand end is greater than 2°C, the No. 4 controller turns off the No. 3 water pump and the water-to-water source heat pump.

[0024] S3, cooling mode:

[0025] The evaporator generates chilled water with a temperature of 5°C to 12°C for cooling; when the internal temperature of the building is lower than the air conditioner set temperature, the user end has no cooling demand, and the No. 6 water pump, the No. 2 three-way valve, the No. 4 water pump and the fan coil unit all stop operating; when the internal temperature of the building is 0.5°C to 1°C higher than the air conditioner set temperature, the user end has cooling demand, the No. 5 controller turns on the No. 6 water pump and the fan coil unit and controls the opening of the No. 2 three-way valve, connecting the fifth circuit, so that the higher temperature chilled water return water flowing out of the return pipe and the lower temperature chilled water out of the bottom outlet of the cold water tank are mixed through the No. 2 three-way valve to reach the fan coil unit inlet temperature set value;

[0026] When the temperature of the chilled water flowing out of the bottom water outlet of the cold water tank cannot meet the cooling demand, that is, when the difference between the fan coil inlet temperature setting value and the temperature of the fifth temperature sensor T5 is less than the setting value, the No. 4 controller turns on the water-water source heat pump, the No. 4 water pump and the No. 5 water pump, and opens the port connected to the No. 1 three-way valve and the cold water tank, the port connected to the No. 1 three-way valve and the No. 4 water pump, and at the same time closes the port connected to the No. 1 three-way valve and the air-water heat exchanger, so that the fourth circuit and the sixth circuit are respectively connected; when the temperature of the chilled water flowing out of the bottom water outlet of the cold water tank meets the cooling demand, that is, when the difference between the fan coil inlet temperature setting value and the temperature of the fifth temperature sensor T5 is greater than the setting value, the No. 4 controller turns off the water-water source heat pump, the No. 4 water pump, the No. 5 water pump and the No. 2 three-way valve, and the cold water tank stops exchanging heat with the water-water source heat pump.

[0027] Compared with the prior art, the present invention has the following advantages:

[0028] (1) The PVT component of the solar-coupled heat pump combined cooling, heating and power system of the present invention is connected to the water-water source heat pump through two water tanks (i.e., a heat collection tank and a domestic hot water tank). Heat is stored in the two water tanks, and the energy storage capacity is significantly increased;

[0029] (2) The PVT components in the solar-coupled heat pump combined cooling, heating and power system of the present invention use phase-change fluid as the heat collection medium. The heat of the PVT components can be quickly taken away through the efficient heat transfer of the phase-change fluid. Since the thermal conductivity of the phase-change fluid is higher than that of the phase-change material, and the heat transfer efficiency can be further increased by adjusting the flow rate, the temperature of the PVT components can be effectively controlled even in high summer temperatures, thereby improving the power generation efficiency and heat collection efficiency of the PVT components.

[0030] (3) The photovoltaic panels on the front of the PVT module absorb solar energy and convert it into electrical energy and thermal energy, which is first supplied to the user end. When there is excess power supplied, the excess power is integrated into the power grid. When the power is insufficient, the power grid is used to supplement the power supply to the user end, thereby reducing energy waste and achieving building energy saving;

[0031] (4) The solar-coupled heat pump combined heating, cooling and power system of the present invention adopts the key technology of the PVT-coupled heat pump and the modular control strategy, realizing the intelligent combination of solar energy and electric energy, giving the system the function of combined heating, cooling and power generation, and is an effective way to improve the comprehensive utilization rate of solar energy and achieve energy conservation and emission reduction in buildings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1Schematic diagram of a solar-coupled heat pump combined cooling, heating, and power system in an embodiment;

[0033] Figure 1 The specific reference numerals are as follows:

[0034] 1-Controller No. 1, 2-Inverter, 3-Controller No. 2, 4-Internal coil, 5-Water pump No. 1, 6-Heat water tank, 7-Controller No. 3, 8-Heat exchanger, 9-Water pump No. 2, 10-Domestic hot water tank, 11-Water pump No. 3, 12-PVT assembly, 13-Condenser, 14-Compressor, 15-Expansion valve, 16-Evaporator, 17-Water pump No. 4, 18-Three-way valve No. 1, 19-Water pump No. 5, 20-Air-water heat exchanger Controller, 21-cold water tank, 22-three-way valve No. 2, 23-controller No. 5, 24-water pump No. 6, 25-fan coil unit, 26-user end, 27-hot water demand end, 28-power grid, 29-cold water inlet, 30-controller No. 4, 31-water-source heat pump, 32-first circuit, 33-second circuit, 34-third circuit, 35-fourth circuit, 36-fifth circuit, 37-sixth circuit, 38-return pipe, 39-return pipe; Figure 1 The arrow in the middle indicates the direction of current or liquid flow. DETAILED DESCRIPTION

[0035] The present invention is further described below in conjunction with the accompanying drawings and embodiments. This embodiment, based on the technical solutions of the present invention, details the system components and operating methods of a solar-coupled heat pump combined cooling, heating, and power system. However, the scope of protection of the present invention is not limited to the following embodiment. Any devices or components not specifically defined herein employ conventional techniques in the art.

[0036] like Figure 1 As shown, the solar-coupled heat pump combined heat and power system of the embodiment includes a power generation-power consumption system, a heat generation-heat storage-heat consumption system and a refrigeration-cold storage-cold consumption system.

[0037] The power generation and power consumption system includes a PVT component 12, an inverter 2, a No. 1 controller 1, a power grid 28, and a user terminal 26 in a building. The photovoltaic panel on the front of the PVT component 12 absorbs solar energy and converts it into electrical energy and thermal energy. The positive and negative poles of the photovoltaic panel on the front of the PVT component 12 are connected to the inverter 2, and the DC to AC conversion is realized through the inverter 2 to generate electricity and connect to the grid; the No. 1 controller 1 is used to manage and adjust the power output of the combined heating, cooling and power supply system.

[0038] The heat generation-heat storage-heat utilization system includes a heat collecting tank 6, a domestic hot water tank 10, a heat exchanger 8, a water-water source heat pump 31, an air-water heat exchanger 20, a No. 2 controller 3, a No. 3 controller 7 and a No. 4 controller 30. The heat collecting tank 6 is provided with an internal coil 4. The back heat dissipation component of the PVT component 12 is connected to the internal coil 4 via a pipeline to form a first circuit 32. The first circuit 32 is equipped with a No. 1 water pump 5 and has a built-in phase change fluid. The liquid outlet of the back heat dissipation component of the PVT component 12 is equipped with a first temperature sensor T1, and the bottom water inlet of the heat collecting tank 6 is equipped with a second temperature sensor T2. The first temperature sensor T1 and the second temperature sensor T2 are connected. The second temperature sensor T2 is connected to the second controller 3 respectively, the upper layer of the heat collecting tank 6 is connected to the bottom water inlet of the domestic hot water tank 10, and the domestic hot water tank 10 is replenished with water by natural gravity flow; the top water outlet of the domestic hot water tank 10 is installed with a third temperature sensor T3 and is connected to a return water pipe 38, the return water pipe 38 is connected to the bottom water inlet of the heat collecting tank 6 through a heat exchanger 8, a second water pump 9 is installed on the return water pipe 38, the heat exchanger 8 is connected to a cold water port 29 and a hot water demand end 27, the cold water port 29 and the hot water demand end 27 are respectively connected to the water pipe of the user end 26, and the cold water port 29 is installed with a fourth temperature sensor The third temperature sensor T3 and the fourth temperature sensor T4 are respectively connected to the No. 3 controller 7. The water-water source heat pump 31 includes a condenser 13 and an evaporator 16. The condenser 13 and the evaporator 16 are connected to the compressor 14 via an expansion valve 15. The condenser 13 and the domestic hot water tank 10 are connected to the second circuit 33 via a pipeline. When solar energy is insufficient, the water-water source heat pump 31 is used to make hot water. The No. 3 water pump 11 is installed on the second circuit 33. The air-water heat exchanger 20 is connected to the evaporator 16 via a pipeline to form a third circuit 34. The No. 1 three-way valve 18 and the No. 4 water pump 17 are installed on the third circuit 34. The air-water heat exchanger 20 It is connected to the condenser 13 via a pipeline to form a fourth loop 35, and a No. 5 water pump 19 is installed on the fourth loop 35. The No. 2 controller 3 is used to control the No. 1 water pump 5, the No. 3 controller 7 is used to control the No. 2 water pump 9, and the No. 4 controller 30 is used to control the No. 3 water pump 11, the No. 4 water pump 17, the No. 5 water pump 19, the No. 1 three-way valve 18 and the water-water source heat pump 31. The heat absorbed by the heat dissipation component on the back of the PVT component 12 is transported to the water collecting tank 6 through the phase change fluid, and the water collecting tank 6 and the domestic hot water tank 10 transport domestic hot water to the hot water demand end 27. When the amount of hot water is insufficient, the water-water source heat pump 31 is started to supplement hot water to the hot water demand end 27.

[0039] The refrigeration-cold storage-cold use system includes a cold water tank 21, a fan coil unit 25 and a No. 5 controller 23. The top water inlet and the bottom water outlet of the cold water tank 21 are respectively installed with a fifth temperature sensor T5 and a sixth temperature sensor T6. The fifth temperature sensor T5 and the sixth temperature sensor T6 are respectively connected to the No. 4 controller 30. The fan coil unit 25 and the cold water tank 21 are connected to form a fifth circuit 36 ​​through a pipeline. The fifth circuit 36 ​​forms a heat exchange loop, and heat is supplied to the user through the fan coil unit 25. The household end 26 is used for cooling. The No. 2 three-way valve 22 and the No. 6 water pump 24 are installed in sequence on the pipeline between the bottom water outlet of the cold water tank 21 and the inlet end of the fan coil 25. The No. 5 controller 23 is used to control the No. 2 three-way valve 22, the No. 6 water pump 24 and the fan coil 25. A return pipe 39 is connected between the top water inlet of the cold water tank 21 and the No. 2 three-way valve 22. The cold water tank 21, the No. 1 three-way valve 18, the No. 4 water pump 17 and the evaporator 16 are connected to form a sixth circuit 37 through a pipeline.

[0040] The working method of the solar-coupled heat pump combined heating, cooling and power system includes power supply mode, heating mode and cooling mode:

[0041] S1, power supply mode:

[0042] The photovoltaic panel on the front of the PVT module 12 absorbs solar energy and converts it into electrical energy and thermal energy. The PVT module 12 supplies power to the user end 26 first through the inverter 2 and the first controller 1. When there is excess power supplied, the excess power is integrated into the power grid 28. When the power is insufficient, the power grid 28 is used to supplement the power supply to the user end 26.

[0043] S2, heating mode:

[0044] The heat absorbed by the heat dissipation component on the back of the PVT assembly 12 is transferred to the heat collecting tank 6 through the phase change fluid. When the temperature difference between the first temperature sensor T1 and the second temperature sensor T2 is not lower than the set value, the No. 2 controller 3 turns on the No. 1 water pump 5. At this time, the first circuit 32 is connected, the PVT assembly 12 dissipates heat through the phase change fluid, and the heat collecting tank 6 stores heat. When the temperature difference between the first temperature sensor T1 and the second temperature sensor T2 is lower than the set value, the No. 2 controller 3 controls the No. 1 water pump 5 to stop, and the PVT assembly 12 stops dissipating heat through the phase change fluid. In the above process, the No. 2 controller 3 controls the start and stop of the No. 1 water pump 5 to achieve the purpose of reducing the temperature of the PVT assembly 12.

[0045] When there is no domestic hot water demand at the hot water demand end 27, the No. 3 controller 7 turns off the No. 2 water pump 9. When there is domestic hot water demand at the hot water demand end 27, the water in the heat collecting tank 6 is input into the domestic hot water tank 10, and the No. 3 controller 7 turns on the No. 2 water pump 9. The cold water at the cold water inlet 29 exchanges heat through the heat exchanger 8, so that the water temperature at the hot water demand end 27 is raised to the temperature set value of the domestic hot water at the hot water demand end 27.

[0046] The water-water source heat pump 31 generates hot water with a temperature of 45°C to 60°C through the condenser 13. When the PVT assembly 12 does not collect enough solar radiation, and the difference between the temperature of the third temperature sensor T3 and the temperature setting value of the domestic hot water at the hot water demand end 27 is not greater than 2°C (that is, the hot water temperature in the water collection tank 6 is insufficient to heat the water temperature in the domestic hot water tank 10 to a temperature that is more than 2°C higher than the temperature setting value of the domestic hot water at the hot water demand end 27), the fourth controller 30 turns on the third water pump 11 and the water-water source heat pump 31 to heat the water. When the water temperature in the domestic hot water tank 10 exceeds the set temperature value of the domestic hot water at the hot water demand end 27 by more than 2°C, the second circuit 33 and the third circuit 34 are connected. When the difference between the temperature of the third temperature sensor T3 and the set temperature value of the domestic hot water at the hot water demand end 27 is greater than 2°C (i.e., the hot water temperature in the heat collecting tank 6 is sufficient to heat the water in the domestic hot water tank 10 to a temperature that exceeds the set temperature value of the domestic hot water at the hot water demand end 27 by more than 2°C), the No. 4 controller 30 turns off the No. 3 water pump 11 and the water-to-water source heat pump 31.

[0047] S3, cooling mode:

[0048] The evaporator 16 produces chilled water at a temperature of 5°C to 12°C for cooling. When the internal temperature of the building is lower than the air conditioning set temperature, the user end 26 has no cooling demand, and the No. 6 water pump 24, the No. 2 three-way valve 22, the No. 4 water pump 17 and the fan coil 25 all stop operating. When the internal temperature of the building is 0.5°C to 1°C higher than the air conditioning set temperature, the user end 26 has cooling demand, and the No. 5 controller 23 turns on the No. 6 water pump 24 and the fan coil 25 and controls the opening of the No. 2 three-way valve 22, connecting the fifth circuit 36, so that the higher temperature chilled water return water flowing out of the return pipe 39 and the lower temperature chilled water out of the bottom outlet of the cold water tank 21 are mixed through the No. 2 three-way valve 22 to reach the set value of the fan coil 25 inlet temperature.

[0049] When the temperature of the chilled water flowing out of the bottom outlet of the cold water tank 21 cannot meet the cooling demand, that is, when the difference between the set value of the inlet temperature of the fan coil 25 and the temperature of the fifth temperature sensor T5 is less than the set value, the No. 4 controller 30 turns on the water-water source heat pump 31, the No. 4 water pump 17 and the No. 5 water pump 19, and opens the port connecting the No. 1 three-way valve 18 to the cold water tank 21 and the port connecting the No. 1 three-way valve 18 to the No. 4 water pump 17, and at the same time closes the No. 1 three-way valve 18 and the air- The ports connected to the water heat exchanger 20 make the fourth circuit 35 and the sixth circuit 37 respectively conductive; when the temperature of the chilled water flowing out of the bottom outlet of the cold water tank 21 meets the cooling requirement, that is, when the difference between the set value of the inlet temperature of the fan coil 25 and the temperature of the fifth temperature sensor T5 is greater than the set value, the No. 4 controller 30 turns off the water-water source heat pump 31, the No. 4 water pump 17, the No. 5 water pump 19 and the No. 2 three-way valve 22, and the cold water tank 21 stops exchanging heat with the water-water source heat pump 31.

Claims

1. A solar-coupled heat pump combined cooling, heating and power system, characterized in that: The combined heat and power system includes a power generation-power consumption system, a heat generation-heat storage-heat consumption system and a refrigeration-cold storage-cold consumption system; the power generation-power consumption system includes a PVT component, an inverter, a power grid and a user end in a building, the positive and negative power generation poles of the photovoltaic panel on the front of the PVT component are connected to the inverter, and the inverter is respectively connected to the power grid and the circuit of the user end; the heat generation-heat storage-heat consumption system includes a heat collection tank, a domestic hot water tank, a heat exchanger, a water-water source heat pump and an air-water heat exchanger, the heat collection tank is provided with an internal coil, the back heat dissipation component of the PVT component is connected to the internal coil via a pipeline to form a first circuit, the first circuit has a built-in phase change fluid, the upper layer of the heat collection tank is connected to the bottom water inlet of the domestic hot water tank, and the top water outlet of the domestic hot water tank is connected to the bottom water inlet of the domestic hot water tank. It is connected to a return water pipeline, which is connected to the bottom water inlet of the heat collecting tank through the heat exchanger. The heat exchanger is connected to a cold water inlet and a hot water demand end, and the cold water inlet and the hot water demand end are respectively connected to the water pipes at the user end. The water-water source heat pump includes a condenser and an evaporator. The condenser is connected to the domestic hot water tank via a pipeline as a second circuit, the air-water heat exchanger is connected to the evaporator via a pipeline as a third circuit, and the air-water heat exchanger is connected to the condenser via a pipeline as a fourth circuit; the refrigeration-cold storage-cold use system includes a cold water tank and a fan coil. The fan coil is connected to the cold water tank via a pipeline as a fifth circuit, the fan coil supplies cold to the user end, and the cold water tank and the evaporator are connected to the sixth circuit via a pipeline.

2. A solar coupled heat pump combined cooling, heating and power system according to claim 1, characterized in that: The front photovoltaic panel of the PVT component absorbs solar energy and converts it into electrical energy and thermal energy. The heat absorbed by the heat dissipation component on the back of the PVT component is transported to the heat collection tank through the phase change fluid. The heat collection tank and the domestic hot water tank transport domestic hot water to the hot water demand end. When the amount of hot water is insufficient, the water-water source heat pump is started to supplement hot water to the hot water demand end.

3. A solar-coupled heat pump combined cooling, heating and power system according to claim 1 or 2, characterized in that: A No. 2 three-way valve is installed on the pipeline between the bottom water outlet of the cold water tank and the inlet end of the fan coil, and a return pipe is connected between the top water inlet of the cold water tank and the No. 2 three-way valve.

4. The solar-coupled heat pump combined cooling, heating and power system according to claim 3, characterized in that: The inverter is connected to a No. 1 controller, and the No. 1 controller is used to manage and adjust the power output of the combined cooling, heating and power system.

5. The solar-coupled heat pump combined cooling, heating and power system according to claim 4, characterized in that: A water pump No. 1 is installed on the first circuit, a first temperature sensor T1 is installed on the liquid outlet of the back heat dissipation component of the PVT assembly, a second temperature sensor T2 is installed on the bottom water inlet of the heat collecting tank, the first temperature sensor T1 and the second temperature sensor T2 are respectively connected to the second controller, a third temperature sensor T3 is installed on the top water outlet of the domestic hot water tank, a fourth temperature sensor T4 is installed on the cold water outlet, the third temperature sensor T3 and the fourth temperature sensor T4 are respectively connected to the third controller, the condenser and the evaporator are connected to the compressor via an expansion valve, a water pump No. 2 is installed on the return pipe, a water pump No. 3 is installed on the second circuit, a three-way valve No. 1 and a water pump No. 4 are installed on the third circuit, and a water pump No. 5 is installed on the fourth circuit. The No. 2 controller is used to control the No. 1 water pump, the No. 3 controller is used to control the No. 2 water pump, and the No. 3 controller is used to control the No. 2 water pump. The No. 3 water pump, the No. 4 water pump, the No. 5 water pump, the No. 1 three-way valve and the water-water source heat pump are controlled by the No. 4 controller.

6. The solar-coupled heat pump combined cooling, heating and power system according to claim 5, characterized in that: The top water inlet and the bottom water outlet of the cold water tank are respectively installed with a fifth temperature sensor T5 and a sixth temperature sensor T6, and the fifth temperature sensor T5 and the sixth temperature sensor T6 are respectively connected to the No. 4 controller. The No. 1 three-way valve and the No. 4 water pump are installed on the sixth circuit. The No. 6 water pump is installed on the pipeline between the No. 2 three-way valve and the inlet end of the fan coil. The No. 2 three-way valve, the No. 6 water pump and the fan coil are controlled by the No. 5 controller.

7. An operating method of the solar coupled heat pump combined cooling, heating and power system according to claim 6, characterized in that: Including power supply mode, heating mode and cooling mode: S1, power supply mode: The front photovoltaic panel of the PVT module absorbs solar energy and converts it into electrical energy and thermal energy. The PVT module preferentially supplies power to the user end through the inverter and the first controller. When there is excess power supplied, the excess power is incorporated into the power grid. When there is insufficient power, the power grid is used to supplement the power supply to the user end. S2, heating mode: The heat absorbed by the heat dissipation component on the back of the PVT assembly is transferred to the heat collecting tank via the phase change fluid. When the temperature difference between the first temperature sensor T1 and the second temperature sensor T2 is not lower than a set value, the second controller turns on the first water pump. At this time, the first circuit is connected, the PVT assembly dissipates heat via the phase change fluid, and the heat collecting tank stores heat. When the temperature difference between the first temperature sensor T1 and the second temperature sensor T2 is lower than a set value, the second controller stops the first water pump, and the PVT assembly stops dissipating heat via the phase change fluid. When there is no domestic hot water demand at the hot water demand end, the No. 3 controller turns off the No. 2 water pump; when there is domestic hot water demand at the hot water demand end, the water in the heat collecting tank is input into the domestic hot water tank, the No. 3 controller turns on the No. 2 water pump, and the cold water at the cold water outlet exchanges heat through the heat exchanger, so that the water temperature at the hot water demand end is raised to the temperature set value of the domestic hot water at the hot water demand end; The water-to-water source heat pump generates hot water with a temperature of 45°C to 60°C through the condenser. When the PVT component does not collect sufficient solar radiation and the difference between the temperature of the third temperature sensor T3 and the temperature setting value of the domestic hot water at the hot water demand end is not greater than 2°C, the No. 4 controller turns on the No. 3 water pump and the water-to-water source heat pump to heat the water in the domestic hot water tank to a temperature that is more than 2°C higher than the temperature setting value of the domestic hot water at the hot water demand end. At this time, the second circuit and the third circuit are connected. When the difference between the temperature of the third temperature sensor T3 and the temperature setting value of the domestic hot water at the hot water demand end is greater than 2°C, the No. 4 controller turns off the No. 3 water pump and the water-to-water source heat pump. S3, cooling mode: The evaporator generates chilled water with a temperature of 5°C to 12°C for cooling; when the internal temperature of the building is lower than the air conditioner set temperature, the user end has no cooling demand, and the No. 6 water pump, the No. 2 three-way valve, the No. 4 water pump and the fan coil unit all stop operating; when the internal temperature of the building is 0.5°C to 1°C higher than the air conditioner set temperature, the user end has cooling demand, the No. 5 controller turns on the No. 6 water pump and the fan coil unit and controls the opening of the No. 2 three-way valve, connecting the fifth circuit, so that the higher temperature chilled water return water flowing out of the return pipe and the lower temperature chilled water out of the bottom outlet of the cold water tank are mixed through the No. 2 three-way valve to reach the fan coil unit inlet temperature set value; When the temperature of the chilled water flowing out of the bottom water outlet of the cold water tank cannot meet the cooling demand, that is, when the difference between the fan coil inlet temperature setting value and the temperature of the fifth temperature sensor T5 is less than the setting value, the No. 4 controller turns on the water-water source heat pump, the No. 4 water pump and the No. 5 water pump, and opens the port connected to the No. 1 three-way valve and the cold water tank, the port connected to the No. 1 three-way valve and the No. 4 water pump, and at the same time closes the port connected to the No. 1 three-way valve and the air-water heat exchanger, so that the fourth circuit and the sixth circuit are respectively connected; when the temperature of the chilled water flowing out of the bottom water outlet of the cold water tank meets the cooling demand, that is, when the difference between the fan coil inlet temperature setting value and the temperature of the fifth temperature sensor T5 is greater than the setting value, the No. 4 controller turns off the water-water source heat pump, the No. 4 water pump, the No. 5 water pump and the No. 2 three-way valve, and the cold water tank stops exchanging heat with the water-water source heat pump.

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