Jet type supercooling enthalpy-increasing solar PVT heat pump combined heat and power generation system

Abstract

The invention relates to a jet type supercooling enthalpy-increasing solar PVT heat pump combined heat and power generation system which comprises a refrigerant system, a hot water system and a power generation-supply integrated system. The system is composed of a compressor, a one-way valve, a fluorine water heat exchanger, a two-phase ejector, a gas-liquid separator, an electronic expansion valve, a heat exchanger, a PVT array, a water pump, a direct-current converter, a municipal power grid and an alternating-current and direct-current inverter, combined heat and power generation is achieved, and energy supply is stable. The jet refrigeration technology and the PVT heat pump technology are combined, the thermodynamic circulation process is improved, throttling loss and overheating loss in the traditional steam compression type circulation process can be greatly reduced, and the system performance is improved; and meanwhile, the refrigerant at the inlet of the PVT array is supercooled by adopting a low injection rate method, so that the liquid supply uniformity of the PVT array is guaranteed, and the heat exchange efficiency of the PVT array is improved. Renewable energy solar energy is fully utilized, energy conservation, high efficiency and low carbon are achieved, and the energy structure is promoted to be transformed to the clean and sustainable development direction.

Description

Technical Field

[0001] The invention belongs to the technical field of solar photovoltaic and thermal technology, and in particular to an ejection-type subcooling enthalpy-increasing solar PVT heat pump cogeneration system. Technical Background

[0002] Solar energy has been widely used in the fields of construction, industry, agriculture, etc. due to its advantages of being green, clean, inexhaustible and inexhaustible. At present, the photovoltaic thermal (PVT) technology effectively integrates solar photovoltaic technology and photothermal technology, reduces the temperature of photovoltaic cells, improves the power generation efficiency of photovoltaics, and at the same time can improve the comprehensive utilization rate of solar energy and achieve cogeneration of heat and power. However, due to the instability, intermittency and volatility of solar radiation, the all-weather production capacity of PVT technology is poor. In view of this, the industry has proposed the PVT heat pump technology that combines PVT technology with heat pump technology to ensure its all-weather production capacity. However, compared with PVT technology, the introduction of compressors in PVT heat pump technology is bound to lead to high energy consumption in system operation, thereby limiting the large-scale application of this technology. Summary of the invention

[0003] In response to the above problems, the purpose of the present invention is to use renewable energy solar energy as the heat source of the system, and rely on jet refrigeration technology, solar PVT technology, and heat pump technology to improve the quality and efficiency of the PVT heat pump system, and help promote the large-scale promotion and application of solar PVT heat pump technology.

[0004] To achieve the above-mentioned purpose, the present invention provides an ejection-type subcooling enthalpy-increasing solar PVT heat pump cogeneration system, the system comprising a refrigerant system, a hot water system, and an integrated production-power supply system;

[0005] The refrigerant system is mainly composed of a compressor 1, a one-way valve 2, a fluorine-water heat exchanger 3, a two-phase ejector 4, a gas-liquid separator 5, an electronic expansion valve 6, a heat exchanger 7, and a PVT array 8. The outlet of the compressor 1 is connected to the one-way valve 2, the fluorine-water heat exchanger 3, the two-phase ejector 4, and the gas-liquid separator 5 in sequence, and is divided into two paths through the gas-liquid separator 5. One path is divided from the top of the gas-liquid separator 5 and connected to the inlet of the compressor 1; the other path is divided into two paths from the bottom of the gas-liquid separator 5, one path is connected to the low-pressure inlet of the two-phase ejector 4 through the electronic expansion valve 6 and the heat exchanger 7, and the other path is connected to the inlet of the compressor 1 through the heat exchanger 7, the PVT array 8, and the gas-liquid separator 5;

[0006] Compressor 1 types include rotor type, scroll type, and piston type;

[0007] Fluorine water heat exchanger 3, heat exchanger 7 types include flat plate type, spiral plate type, plate fin type, immersed spiral tube type, sleeve type, shell and tube type;

[0008] The electronic expansion valve 6 can be replaced by a thermal expansion valve or a capillary tube;

[0009] The flow channel types of the heat exchange elements of the PVT array 8 include triangle, quadrilateral, hexagon, circle, diamond, spindle, teardrop, and honeycomb.

[0010] The hot water system is mainly composed of a fluorine-water heat exchanger 3 and a water pump 9. The water pump 9 is connected to the water side of the fluorine-water heat exchanger 3 via a water pipeline.

[0011] The production-power supply integration system mainly consists of a PVT array 8, a DC converter 10, a municipal power grid 11, and an AC-DC inverter 12. The production-power supply integration system is divided into two routes, one route is connected to the PVT array 8 and the DC converter 10, and the other route is connected to the municipal power grid 11 and the AC-DC inverter 12. The above two routes are connected to the compressor 1 and the water pump 9 after being combined through the outlet of the DC converter 10 and the outlet of the AC-DC inverter 12;

[0012] The types of solar cell elements of the PVT array 8 include monocrystalline silicon, polycrystalline silicon, copper indium gallium selenide, gallium arsenide, cadmium telluride, and perovskite;

[0013] The motors of the compressor 1 and the water pump 9 are DC driven, and their types include brushless DC, brushed DC, and permanent magnet DC.

[0014] Beneficial effects of the present invention:

[0015] The present invention comprehensively utilizes the short-wave radiation and long-wave radiation of solar energy, thereby improving the comprehensive utilization rate of renewable energy solar energy;

[0016] The present invention combines the jet refrigeration technology with the PVT heat pump technology, which can effectively reduce the throttling loss and superheating loss in the traditional steam compression cycle;

[0017] The present invention uses an ejector with a low ejection rate to achieve supercooling of the circulating working fluid at the inlet of the PVT array, thereby improving the uniformity of the liquid supply of the PVT array, increasing the enthalpy difference of the unit mass of the phase-change working fluid, and thus optimizing the heat exchange efficiency of the PVT array;

[0018] The system of the present invention is energy and power independent, energy-saving, high-efficiency, green and low-carbon. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of a jet-type subcooling enthalpy-increasing solar PVT heat pump cogeneration system of the present invention;

[0020] Numbers in the figure: 1-compressor, 2-check valve, 3-fluorine-water heat exchanger, 4-two-phase ejector, 5-gas-liquid separator, 6-electronic expansion valve, 7-heat exchanger, 8-PVT array, 9-water pump, 10-DC converter, 11-municipal power grid, 12-AC / DC inverter. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] like Figure 1 As shown, in this embodiment, an ejection-type subcooling enthalpy-increasing solar PVT heat pump cogeneration system includes a refrigerant system, a hot water system, and an integrated production-power supply system.

[0023] The refrigerant system is mainly composed of a compressor 1, a one-way valve 2, a fluorine-water heat exchanger 3, a two-phase ejector 4, a gas-liquid separator 5, an electronic expansion valve 6, a heat exchanger 7, and a PVT array 8 through a refrigerant pipeline;

[0024] The hot water system is mainly composed of a fluorine-water heat exchanger 3 and a water pump 9 connected via a water pipeline;

[0025] The integrated production and power supply system mainly consists of a PVT array 8, a DC converter 10, a municipal power grid 11, and an AC / DC inverter 12 connected via circuits.

[0026] This embodiment is an ejection-type subcooling enthalpy-increasing solar PVT heat pump cogeneration system, which can realize self-generation and self-use of electricity, grid connection of surplus electricity and hot water supply.

[0027] like Figure 1As shown, the compressor 1, the electronic expansion valve 6, and the water pump 9 are turned on, the PVT array 8 is the evaporator, and the fluorine-water heat exchanger 3 is the condenser. The working principle is as follows: the low-temperature and low-pressure gaseous refrigerant is compressed by the compressor 1 into a high-temperature and high-pressure gaseous refrigerant, enters the fluorine-water heat exchanger 3 through the one-way valve 2 to release heat into the hot water system, and the high-temperature and high-pressure gaseous refrigerant is then condensed into a medium-temperature and high-pressure liquid refrigerant, and then enters the two-phase ejector 4 to eject the low-pressure gas and become a medium-pressure gas-liquid two-phase refrigerant, and then undergoes gas-liquid separation. The refrigerant is separated into saturated gaseous refrigerant and saturated liquid refrigerant by the refrigerant separator 5. The saturated gaseous refrigerant returns to the compressor 1, and the saturated liquid refrigerant is divided into two paths: one path is throttled and depressurized by the electronic expansion valve 6 to become a gas-liquid two-phase refrigerant, and then absorbs heat through the heat exchanger 7 to become a superheated refrigerant and enter the two-phase ejector 4 to be ejected; the other path is cooled to a supercooled refrigerant after passing through the heat exchanger 7, enters the PVT array to absorb solar energy and air energy, boils into a gaseous refrigerant, and then returns to the compressor 1 after passing through the gas-liquid separator 5. The hot water enters the fluorine water heat exchanger 3 driven by the water pump 9 to absorb heat, and is continuously heated in this cycle. In addition, the PVT array 8 cells absorb short-wave solar radiation and convert solar energy into DC power, which is then converted into DC 750V via a DC converter 10 for use by the compressor 1 and the water pump 9. If the power output of the PVT array 8 is greater than the power consumption of the system, the excess power is connected to the grid via an AC / DC inverter 12; if the power output of the PVT array 8 is less than the power consumption of the system, the grid is converted into DC 750V via an AC / DC inverter 12 for use by the compressor 1 and the water pump 9.

[0028] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the invention, and the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. An ejection-type subcooling enthalpy-increasing solar PVT heat pump cogeneration system, the system comprising a refrigerant system, a hot water system, and an integrated production-power supply system; The refrigerant system is mainly composed of a compressor (1), a one-way valve (2), a fluorine-water heat exchanger (3), a two-phase ejector (4), a gas-liquid separator (5), an electronic expansion valve (6), a heat exchanger (7), and a PVT array (8). The outlet of the compressor (1) is connected to the one-way valve (2), the fluorine-water heat exchanger (3), the two-phase ejector (4), and the gas-liquid separator (5) in sequence, and is divided into two paths through the gas-liquid separator (5). One path is divided from the top of the gas-liquid separator (5) and connected to the inlet of the compressor (1); the other path is divided into two paths from the bottom of the gas-liquid separator (5). One path is connected to the low-pressure inlet of the two-phase ejector (4) through the electronic expansion valve (6) and the heat exchanger (7), and the other path is connected to the inlet of the compressor (1) through the heat exchanger (7), the PVT array (8), and the gas-liquid separator (5). The hot water system is mainly composed of a fluorine-water heat exchanger (3) and a water pump (9), and the water side of the fluorine-water heat exchanger (3) is connected to the water pump (9) via a water pipeline; The integrated production and power supply system mainly consists of a PVT array (8), a DC converter (10), a municipal power grid (11), and an AC / DC inverter (12). The integrated production and power supply system is divided into two routes, one route is connected between the PVT array (8) and the DC converter (10), and the other route is connected between the municipal power grid (11) and the AC / DC inverter (12). The two routes are connected to the compressor (1) and the water pump (9) after being combined through the outlet of the DC converter (10) and the outlet of the AC / DC inverter (12).

2. The jet-type subcooling enthalpy-increasing solar PVT heat pump cogeneration system according to claim 1 is characterized in that: The types of compressors (1) include rotor type, scroll type and piston type.

3. The jet-type subcooling enthalpy-increasing solar PVT heat pump cogeneration system according to claim 1 is characterized in that: The types of the fluorine-water heat exchanger (3) and the heat exchanger (7) include flat plate type, spiral plate type, plate rib type, immersed spiral tube type, sleeve type, and shell and tube type.

4. The jet-type subcooling enthalpy-increasing solar PVT heat pump cogeneration system according to claim 1 is characterized in that: The electronic expansion valve (6) may be replaced by a thermal expansion valve or a capillary tube.

5. The jet-type subcooling enthalpy-increasing solar PVT heat pump cogeneration system according to claim 1 is characterized in that: The types of solar cell elements of the PVT array (8) include monocrystalline silicon, polycrystalline silicon, copper indium gallium selenide, gallium arsenide, cadmium telluride, and perovskite.

6. The jet-type subcooling enthalpy-increasing solar PVT heat pump cogeneration system according to claim 1 is characterized in that: The flow channel types of the heat exchange elements of the PVT array (8) include triangle, quadrilateral, hexagon, circle, diamond, spindle, teardrop, and honeycomb.

7. The jet-type subcooling enthalpy-increasing solar PVT heat pump cogeneration system according to claim 1 or 2, characterized in that: The motors of the compressor (1) and the water pump (9) are DC-driven, and their types include brushless DC, brushed DC, and permanent magnet DC.

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