PVT heat pump system capable of achieving day-night time-shared combined cooling, heating and power using solar radiation and sky cold radiation

Abstract

The present invention provides a photovoltic and thermal (PVT) heat pump system capable of achieving day-night time-shared combined cooling, heating and power using solar radiation and sky cold radiation. The system utilizes a photovoltaic power generation technology and a photovoltic and thermal (PVT heat pump technology simultaneously, both of which are relatively independent and promoted to each other in the function. The main energy sources of the system are solar radiation energy and sky long-wave cold radiation energy, and the energy is respectively transformed into electric energy, thermal energy and cold energy via a photovoltic and thermal (PVT) photoelectric-evaporation/condensation module at different times in different working modes. The system of the present invention integrates power generation. heating, refrigeration and many other functions; and the equipment has simple composition, high utilization rate and remarkable energy-saving effect, thereby improving the energy utilization rate to the maximum extent, and achieving a multi-purpose machine and day-night time-shared combined cooling, heat and power.

Claims

1. A photovoltic and thermal (PVT) heat pump system capable of achieving day-night time-shared combined cooling, heating and power using solar radiation and sky cold radiation, utilizing a photovoltaic power generation technology and a PVT heat pump technology simultaneously, both of which are relatively independent and promoted to each other in the function, the main energy sources of the systems are solar radiation energy and sky long-wave cold radiation energy, and the energy transfer mode includes radiation and heat conduction, and the heat convection is supplemented, thereby achieving the output of electric energy, thermal energy and cold energy on the same system at different times in different working modes, and achieving a multi-purpose machine and day-night time-shared combined cooling heat and power, wherein the PVT heat pump system comprises a PVT photoelectric-evaporation/condensation module, a compressor, a four-way reversing valve, a heat storage water tank, a dry filter, an electronic expansion valve, a one-way refrigerant valve group and a cooling terminal evaporator; with the control of the four-way reversing valve and refrigerant solenoid valves, the switching of a heating/refrigeration mode of the heat pump is achieved; and a power system comprises an inverter; when working in a combined heating and power mode by day with strong solar radiation intensity, the refrigerant in the PVT heat pump system is connected to an inlet of an efficient heat exchanger as a condenser of the heat pump system in the heat storage water tank through the four-way reversing valve after be exhausted by the compressor, and an outlet of the efficient heat exchanger is successively connected to the dry filter and the electronic expansion valve after passing through the one-way refrigerant valve group and then, connected to an inlet of the PVT photoelectric-evaporation/condensation module as an evaporator of the PVT heat pump system; a liquid refrigerant is evaporated through heat absorption in the PVT photoelectric-evaporation/condensation module; the volume thereof is gradually increased; a refrigerant channel is also gradually shunted along a pipeline, and shunted into a multi-pipe system from a two-pipe system; the refrigerant flows out from the outlet and is connected to a steam absorption opening of the compressor through the four-way reversing valve, to form a closed heating cycle of the heat pump system; the inlet and the outlet of the efficient heat exchanger arranged in the heat storage water tank are respectively controlled by a third refrigerant solenoid valve and a fourth refrigerant solenoid valve; and the efficient heat exchanger arranged in the heat storage water tank directly heats the water in the heat storage water tank, and the water is taken as a heat source of heating or domestic hot water; and when working in the refrigeration mode in summer and a night of a transition season having a cold demand and by day of cloudy and rainy weather, the refrigerant in an outlet of the cooling terminal evaporator enters into the compressor through the four-way reversing valve for steam exhaust, and then, is connected to the inlet of the PVT photoelectric-evaporation/condensation module as the condenser of the PVT heat pump system; gas refrigerant is condensed through heat release in the PVT photoelectric-evaporation/condensation module from gas to the liquid; the volume is gradually reduced; the refrigerant channel is also converged to the two-pipe system from the multi-pipe system; and finally, the refrigerant flows out from the outlet, is successively connected to the dry filter and the electronic expansion valve after passing through the one-way refrigerant valve group, and enters into an inlet of the cooling terminal evaporator; the outlet and the inlet of the cooling terminal evaporator are respectively controlled by a first refrigerant solenoid valve and a second refrigerant solenoid valve; and cold generated by the PVT heat pump system is transported to each cold area through each evaporator at the cooling terminal, or is transported to the cold areas having different cold demands in the different times through storage.

2. The PVT heat pump system capable of achieving day-night time-shared combined cooling, heating and power using solar radiation and sky cold radiation according to claim 1, wherein the one-way refrigerant valve group is connected into a ring by four one-way valves, which is divided into two groups connected in opposite directions; and the dry filter and the electronic expansion valve are respectively connected between the two groups of one-way valves, to guarantee that the refrigerant always flows from the dry filter to the electronic expansion valve.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic diagram of systematic circulation of a heating mode of a PVT heat pump system capable of achieving day-night time-shared combined cooling, heating and power using solar radiation and sky cold radiation.

(2) FIG. 2 is a schematic diagram of systematic circulation of a refrigeration mode of a PVT heat pump system capable of achieving day-night time-shared combined cooling, heating and power using solar radiation and sky cold radiation.

(3) FIG. 3 is a diagram of a structural form of a PVT photoelectric-evaporation/condensation module.

(4) In the figures: 1-PVT photoelectric-evaporation/condensation module; 2-Compresosr; 3-Four-way reversing valve;

(5) 4-Heat storage water tank; 5-Dry filter; 6-Electronic expansion valve; 7-One-way refrigerant valve group;

(6) 8-First refrigerant solenoid valve; 9-Second refrigerant solenoid valve; 10-Third refrigerant solenoid valve;

(7) 11-Fourth refrigerant solenoid valve; and 12-Photovoltaic inverter.

DETAILED DESCRIPTION

(8) A PVT heat pump system capable of achieving day-night time-shared combined cooling, heating and power using solar radiation and sky cold radiation is provided. The system utilizes the photovoltaic power generation technology and the PVT heat pump technology simultaneously, both of which are relatively independent and promoted to each other in the function. The system can be operated around the clock. The main energy sources of the system are solar radiation energy and sky long-wave cold radiation energy, and the main energy transfer mode includes radiation and heat conduction, and the heat convection is supplemented, thereby achieving the output of electric energy, thermal energy and cold energy on the same system at different times in different working modes, and achieving a multi-purpose machine and day-night time-shared combined cooling heat and power.

(9) The PVT heat pump system has simple equipment composition and simplified system form, and is mainly composed of a machine set, an outdoor machine and an indoor machine. The outdoor machine is a PVT photoelectric-evaporation/condensation module 1 which acts as an evaporator and a condenser of the PVT heat pump system and is also equipment that generates power using a photovoltaic effect by day; the machine set is mainly composed of a compressor 2, a four-way reversing valve 3, a dry filter 5, an electronic expansion valve 6 and a one-way refrigerant valve group 7; and the indoor machine has many forms, includes a heat storage water tank 4 for heat utilization and a cold equipment evaporator used for ends, and can be used for direct cold supply as well as cold storage and supply of different time periods. With the control of the four-way reversing valve 3 and refrigerant solenoid valves 8-11, the switching of a heating/refrigeration mode of the heat pump is achieved; and a power system is composed of an inverter, a power distribution cabinet, a battery and the like.

(10) As shown in FIG. 1, in winter, summer and the day having strong solar radiation intensity in the transition season, the system could work in the combined heating and power mode. At this time, the PVT photoelectric-evaporation/condensation module as the evaporator of the PVT heat pump system absorbs heat. The absorbed heat mainly includes solar radiation energy, heat conduction quality to a heat exchange plate through heating of the photoelectric module, and heat exchange quantity formed by natural convection between the heat exchange plate and air. The refrigerant in the PVT heat pump system is connected to an inlet of an efficient heat exchanger as a condenser of the heat pump system in the heat storage water tank 4 through the four-way reversing valve 3 after be exhausted by the compressor 2, and an outlet of the efficient heat exchanger is successively connected to the dry filter 5 and the electronic expansion valve 6 after passing through the one-way refrigerant valve group 7, and then, connected to an inlet of the PVT photoelectric-evaporation/condensation module 1. A liquid refrigerant is evaporated through heat absorption in the PVT photoelectric-evaporation/condensation module 1; the volume thereof is gradually increased; a refrigerant channel is also gradually shunted along a pipeline, and shunted into a multi-pipe system from a two-pipe system; the refrigerant flows out from the outlet and is connected to a steam absorption opening of the compressor 2 through the four-way reversing valve 3, to form a closed heating cycle of the heat pump system. The inlet and the outlet of the efficient heat exchanger are respectively controlled by a third refrigerant solenoid valve 10 and a fourth refrigerant solenoid valve 11; and the efficient heat exchanger arranged in the heat storage water tank 4 directly heats the water in the heat storage water tank 4, and the water is taken as a heat source of heating or domestic hot water.

(11) As shown in FIG. 2, in summer and a night of a transition season having a cold demand and by day of cloudy and rainy weather with low solar radiation intensity, the system could work in the refrigeration mode, and the PVT photoelectric-evaporation/condensation module as the condenser of the heat pump system releases the heat. Heat exchange energy sources mainly include sky long-wave cold radiation energy, and heat exchange quantity formed by natural convection between the heat exchange plate and air and wind and washing. The refrigerant in an outlet of the cooling terminal evaporator enters into the compressor 2 through the four-way reversing valve 3 for steam exhaust, and then, is connected to the inlet of the PVT photoelectric-evaporation/condensation module 1; gas refrigerant is condensed through heat release in the PVT photoelectric-evaporation/condensation module 1 from gas to the liquid; the volume is gradually reduced; the refrigerant channel is also converged to the two-pipe system from the multi-pipe system; and finally, the refrigerant flows out from the outlet, is successively connected to the dry filter 5 and the electronic expansion valve 6 after passing through the one-way refrigerant valve group 7, and enters into an inlet of the cooling terminal evaporator; the outlet and the inlet of the cooling terminal evaporator are respectively controlled by a first refrigerant solenoid valve 8 and a second refrigerant solenoid valve 9; and cold generated by the PVT heat pump system is transported to each cold area through each evaporator at the cooling terminal, and could also be transported to the cold areas having different cold demands in the different times through storage.

(12) The one-way refrigerant valve group 7 is connected into a ring by four one-way valves, which is divided into two groups connected in opposite directions; and the dry filter 5 and the electronic expansion valve 6 are respectively connected between the two groups of one-way valves, to guarantee that the refrigerant always flows from the dry filter 5 to the electronic expansion valve 6.

(13) The PVT photoelectric-evaporation/condensation module 1 is laminated by an efficient roll-bond heat exchange plate and a photovoltaic module. The heat exchange plate is made by single-sided inflatable processing of an all-aluminum plate, a flat plate is located on a top surface of the heat exchange plate, and the refrigerant channel is located on a bottom surface, is a serpentine coiled pipe channel, and is gradually shunted into the multi-pipe system from the two-pipe system of the inlet. Both a shunt position and a converging position are transited by a smooth pipeline, and three connectors, i.e. one inlet and two outlets, are arranged. To improve the anti-deformation strength of the heat exchange plate, the periphery of the heat exchange plate is made into an L-shaped downward edgefold, and the surface of the heat exchange plate is sprayed with a selective absorbing coating beneficial to enhancing the spectral absorption capability. The inflatable technology needs the technologies of drawing channel form diagrams, welding, hot rolling, cold rolling and annealing, and finally integral blowing is required with nitrogen. This process ensures that one side is flat and the other side is protruded outwards. The pipeline is blown into a semicircular channel. The flat plate on the top surface is closely combined with the photovoltaic module through lamination more easily, thereby reducing the heat transfer resistance, increasing the heat conductivity, and improving the energy utilization rate. The photovoltaic module is a black photovoltaic backboard to enhance the spectral absorption capability and increase the heat conduction strength. An EVA glue film, as a viscous medium, is placed between the photovoltaic module and the heat exchange plate.

(14) The PVT heat pump system capable of achieving day-night time-shared combined cooling, heating and power using solar radiation and sky cold radiation adopts the PVT heat pump system, thereby greatly improving the efficiency of the module and the performance coefficient of the heat pump system. Through the heat pump cycle, the heat of the photovoltaic module in its generation process is taken away, thereby playing a role of cooling a photovoltaic battery piece, and remarkably improving the generating capacity and generating efficiency of the system. Two systems are promoted to each other. The whole system could achieve the self-sufficiency of the electric energy, the generating capacity of daytime is sufficient to supply the power consumption equipment in the system for using around the clock.

(15) The PVT heat pump system capable of achieving day-night time-shared combined cooling, heating and power using solar radiation and sky cold radiation integrates the heat supply, refrigeration, power generation and other functions. The system has simple equipment composition, high utilization rate of operation equipment around the clock and remarkable energy-saving effect, and could improve the energy utilization rate to the maximum extent, thereby achieving the day-night time-shared combined cooling, heating and power. The system is a green energy-saving and environment-friendly compound energy system having wide scope of application and great promotion value.