Double-jet synergistic solar PVT-air source coupling heat pump combined heat and power generation system

Abstract

The invention relates to a double-jet synergistic solar PVT-air source coupling heat pump combined heat and power generation system which comprises a refrigerant system, a hot water system and a power supply system. The system is composed of a compressor, a one-way valve, a hot water heat exchanger, a two-phase ejector, a gas-liquid separator, a first electronic expansion valve, a second electronic expansion valve, a PVT array, a finned heat exchanger, a first three-way valve, a second three-way valve, a steam ejector, a water pump, a direct-current converter, a municipal power grid and an alternating-current and direct-current inverter, and synchronous output of heat energy and electric energy can be achieved. According to the system, double evaporation temperatures can be achieved, free switching between a main heat source and an auxiliary heat source of the system is achieved according to heat source conditions of outdoor solar energy and air energy, multi-energy complementation is achieved, and energy supply of the system is reliable and stable; according to the embodiment of the invention, throttling loss and overheating loss in a traditional steam compression type heat pump system are effectively reduced by utilizing a double-injection technology, and the system is energy-saving, efficient, green, low-carbon and low in operation cost, and has popularization and application values.

Description

Technical Field

[0001] The present invention belongs to the technical field of solar photovoltaic-thermal-air energy heat pump, in particular to a double-injection efficiency-enhanced solar PVT-air source coupled heat pump cogeneration system. Technical Background

[0002] Solar energy is a clean, efficient, and inexhaustible renewable energy source, which is mainly utilized in the form of solar photovoltaic and photothermal. Photovoltaic Thermal (PVT) heat pump technology integrates solar photovoltaic, photothermal, and heat pump technologies, which reduces the surface temperature of photovoltaics, improves the efficiency of photovoltaic power generation, and improves the comprehensive utilization rate of solar energy to achieve cogeneration of heat and power. However, due to the periodicity, intermittency, low and uneven energy density of solar energy, the production capacity of PVT heat pump technology is relatively unstable, and it is difficult to achieve continuous and stable energy output, which limits the large-scale promotion and application of this technology. Therefore, it is urgent to explore a multi-source, stable, and efficient heat pump technology path that complements the renewable energy solar energy. Summary of the invention

[0003] In view of the above problems, the purpose of the present invention is to use renewable energy sources such as solar energy and air energy as the heat source of the system, and integrate dual injection technology, solar PVT technology, and multi-source coupled heat pump technology to achieve stable, efficient, green, and low-carbon energy output of the system.

[0004] To achieve the above-mentioned purpose, an embodiment of the present invention provides a dual-injection efficiency-enhanced solar PVT-air source coupled heat pump cogeneration system, the system comprising a refrigerant system, a hot water system, and a power supply system;

[0005] The refrigerant system is mainly composed of a compressor, a one-way valve, a hot water heat exchanger, a two-phase ejector, a gas-liquid separator, an electronic expansion valve 1, an electronic expansion valve 2, a PVT array, a finned heat exchanger, a three-way valve 1, a three-way valve 2, and a steam ejector. The compressor outlet is connected to the one-way valve and the hot water heat exchanger in sequence, and then connected to the gas-liquid separator after entering the two-phase ejector for injection, and then divided into two paths. One of the paths is separated from the top of the gas-liquid separator and connected to the compressor inlet, and the other path is separated into two paths from the bottom of the gas-liquid separator. One of the paths: after passing through the electronic expansion valve 1 and the PVT array, it is divided into two paths again, one path is connected to the high-pressure inlet end of the steam ejector through the three-way valve 1, and the other path is connected to the low-pressure inlet end of the steam ejector through the three-way valve 2; the other path separated from the bottom of the gas-liquid separator: after passing through the electronic expansion valve 2 and the finned heat exchanger, it is divided into two paths again, one path is connected to the high-pressure inlet end of the steam ejector through the three-way valve 1, and the other path is connected to the low-pressure inlet end of the steam ejector through the three-way valve 2; the steam ejector is connected to the low-pressure inlet end of the two-phase ejector;

[0006] Compressor types include rotary, scroll, and piston;

[0007] Types of hot water heat exchangers include flat plate, spiral plate, plate fin, immersed spiral tube, shell and tube, and shell and tube;

[0008] Electronic expansion valve 1 and electronic expansion valve 2 can be replaced by thermal expansion valve and capillary tube;

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

[0010] The hot water system is mainly composed of a hot water heat exchanger and a water pump. The water side of the hot water heat exchanger is connected to the water pump through a water pipeline.

[0011] The power supply system is mainly composed of a PVT array, a DC converter, a municipal power grid, and an AC / DC inverter. The power supply system is divided into two routes, one route is connected to the PVT array and the DC converter, and the other route is connected to the municipal power grid and the AC / DC inverter. The above two routes are connected to the compressor, the fan of the finned heat exchanger, and the water pump after being combined through the DC converter outlet and the AC / DC inverter outlet;

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

[0013] The motors of compressors, fans of finned heat exchangers, and water pumps are DC driven, and their types include brushless DC, brushed DC, and permanent magnet DC.

[0014] By controlling the compressor, electronic expansion valve 1, electronic expansion valve 2, fan of finned heat exchanger, three-way valve 1, three-way valve 2, and water pump on and off, the system can switch between the following two operating modes:

[0015] Mode 1, compressor, electronic expansion valve 1, electronic expansion valve 2, fan of finned heat exchanger, three-way valve 1, water pump are turned on, and the system operates in a coupled heat pump cogeneration mode with solar energy as the main heat source and air energy as the auxiliary heat source;

[0016] Mode 2, the compressor, electronic expansion valve 1, electronic expansion valve 2, fan of the finned heat exchanger, three-way valve 2, and water pump are turned on, and the system operates in a coupled heat pump cogeneration mode with air energy as the main heat source and solar energy as the auxiliary heat source.

[0017] Beneficial effects of the present invention:

[0018] The embodiment of the present invention can fully and synchronously utilize the renewable energy sources of solar energy and air energy, and the utilization rate of the renewable energy of the system is high;

[0019] The embodiment of the present invention can achieve dual evaporation temperature matching of solar energy and air energy of different qualities, and can realize free switching of the main heat source and auxiliary heat source of the system according to the outdoor solar energy and air energy heat source conditions, and the utilization rate of low-quality heat sources is high;

[0020] The embodiment of the present invention can realize the complementarity between solar energy and air energy, and the system energy supply is reliable and stable;

[0021] The embodiment of the present invention can combine the ejector refrigeration technology with the multi-source coupled heat pump technology, and the thermodynamic cycle process is improved, which can greatly reduce the throttling loss and superheating loss of the traditional steam compression cycle process, and improve the compressor efficiency and system energy efficiency;

[0022] The system of the embodiment of the present invention is self-sufficient in production capacity, and the system is highly efficient, energy-saving, low-carbon, and has low operating costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of the principle of a dual-injection efficiency-enhancing solar PVT-air source coupled heat pump cogeneration system according to an embodiment of the present invention;

[0024] Figure 2 It is a schematic diagram of the principle of the coupled heat pump cogeneration mode of the present invention using solar energy as the main heat source and air energy as the auxiliary heat source;

[0025] Figure 3 It is a schematic diagram of the principle of a coupled heat pump cogeneration mode with air energy as the main heat source and solar energy as the auxiliary heat source according to an embodiment of the present invention.

[0026] Numbers in the figure: 1-compressor, 2-check valve, 3-hot water heat exchanger, 4-two-phase ejector, 5-gas-liquid separator, 6-electronic expansion valve one, 7-electronic expansion valve two, 8-PVT array, 9-fin heat exchanger, 10-three-way valve one, 11-three-way valve two, 12-steam ejector, 13-water pump, 14-DC converter, 15-municipal power grid, 16-AC / DC inverter. DETAILED DESCRIPTION

[0027] 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.

[0028] like Figure 1 As shown, in this embodiment, a double-injection efficiency-enhanced solar PVT-air source coupled heat pump cogeneration system includes a refrigerant system, a hot water system, and a power supply system.

[0029] The refrigerant system is mainly composed of a compressor 1, a one-way valve 2, a hot water heat exchanger 3, a two-phase ejector 4, a gas-liquid separator 5, an electronic expansion valve 1 6, an electronic expansion valve 2 7, a PVT array 8, a finned heat exchanger 9, a three-way valve 1 10, a three-way valve 2 11, and a steam ejector 12 connected via a refrigerant pipeline;

[0030] The hot water system is mainly composed of a hot water heat exchanger 3 and a water pump 13 connected via a water pipeline;

[0031] The power supply system mainly consists of a PVT array 8, a DC converter 14, a municipal power grid 15, and an AC / DC inverter 16 connected via circuits.

[0032] In this embodiment, by controlling the opening and closing of the compressor 1, the electronic expansion valve 1 6, the electronic expansion valve 2 7, the fan of the finned heat exchanger 9, the three-way valve 1 10, the three-way valve 2 11, and the water pump 13, the system can realize the switching between the coupled heat pump cogeneration mode with solar energy as the main heat source and air energy as the auxiliary heat source and the coupled heat pump cogeneration mode with air energy as the main heat source and solar energy as the auxiliary heat source.

[0033] (1) When the solar heat source is better than the air heat source, such as when the outdoor solar radiation intensity is high and the ambient temperature is low, the system operates in a coupled heat pump cogeneration mode with solar energy as the main heat source and air energy as the auxiliary heat source. The compressor 1, electronic expansion valve 1 6, electronic expansion valve 2 7, fan of finned heat exchanger 9, three-way valve 1 10, and water pump 13 are turned on. At this time, if Figure 2As shown, 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 hot 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 gaseous refrigerant and mix with it to form a gas-liquid two-phase refrigerant, and enters the gas-liquid separator 5 to be separated into gaseous refrigerant and liquid refrigerant. The gaseous refrigerant is withdrawn by the compressor 1, and the liquid refrigerant is divided into two paths. : One path is throttled and depressurized by electronic expansion valve 16 to become gas-liquid two-phase refrigerant, then enters PVT array 8 to absorb the main heat source - solar energy to become superheated gaseous refrigerant, and enters the high-pressure inlet end of steam ejector 12 through three-way valve 10; the other path is throttled and depressurized by electronic expansion valve 27 (the degree of throttling and depressurization is greater than the previous path) to become gas-liquid two-phase refrigerant, then enters finned heat exchanger 9 to absorb auxiliary heat source - air energy to become superheated gaseous refrigerant, and enters the low-pressure inlet section of steam ejector 12 through three-way valve 211 to be ejected. Driven by water pump 13, hot water enters hot water heat exchanger 3 to absorb heat, and thus circulates and is continuously heated. In addition, PVT array 8 converts solar energy into DC power, and converts it into a specific DC voltage for system use through DC converter 14. If the power generated by PVT array 8 is greater than the power consumption of the system, the surplus power is connected to the grid through AC-DC inverter 16; if the power generated by PVT array 8 is less than the power consumption of the system, the grid is converted into a specific DC voltage for system use through AC-DC inverter 16.

[0034] (2) When the solar energy heat source is inferior to the air energy heat source, such as when the outdoor solar radiation intensity is low and the ambient temperature is high, the system operates in a coupled heat pump cogeneration mode with air energy as the main heat source and solar energy as the auxiliary heat source. The compressor 1, electronic expansion valve 1 6, electronic expansion valve 2 7, fan of finned heat exchanger 9, three-way valve 2 11, and water pump 13 are turned on. At this time, if Figure 3As shown, 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 hot 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 gaseous refrigerant and mix with it to form a gas-liquid two-phase refrigerant, and enters the gas-liquid separator 5 to be separated into gaseous refrigerant and liquid refrigerant. The gaseous refrigerant is withdrawn by the compressor 1, and the liquid refrigerant is divided into two paths. : One path is throttled and depressurized by the electronic expansion valve 16 to become a gas-liquid two-phase refrigerant, and then enters the PVT array 8 to absorb the auxiliary heat source - solar energy to become a superheated gaseous refrigerant, and enters the low-pressure inlet end of the steam ejector 12 through the three-way valve 11 to be ejected; the other path is throttled and depressurized by the electronic expansion valve 27 (the degree of throttling and depressurization is smaller than the previous path) to become a gas-liquid two-phase refrigerant, and then enters the finned heat exchanger 9 to absorb the main heat source - air energy to become a superheated gaseous refrigerant, and enters the high-pressure inlet section of the steam ejector 12 through the three-way valve 10. Driven by the water pump 13, the hot water enters the hot water heat exchanger 3 to absorb heat, and thus circulates and is continuously heated. In addition, the PVT array 8 converts solar energy into DC power, and converts it into a specific DC voltage for the system through the DC converter 14. If the power generated by the PVT array 8 is greater than the power consumption of the system, the surplus power is connected to the grid through the AC-DC inverter 16; if the power generated by the PVT array 8 is less than the power consumption of the system, the grid is converted into a specific DC voltage for the system through the AC-DC inverter 16.

[0035] (3) When the solar heat source is close to the air heat source, the system operates in a coupled heat pump cogeneration mode with air energy as the main heat source and solar energy as the auxiliary heat source. The frequency of the fan of the finned heat exchanger 9 is reduced to provide high-pressure superheated gaseous refrigerant to the high-pressure inlet of the steam ejector 12; the electronic expansion valve 4 is controlled to provide low-pressure superheated gaseous refrigerant to the low-pressure inlet of the steam ejector 12, thereby reducing the surface temperature of the PVT array 8 and improving its power generation efficiency. The compressor 1, the electronic expansion valve 1 6, the electronic expansion valve 2 7, the fan of the finned heat exchanger 9, the three-way valve 2 11, and the water pump 13 are turned on. At this time, if Figure 3 As shown, the working principle is as described in (2).

[0036] 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. A double-injection efficiency-enhanced solar PVT-air source coupled heat pump cogeneration system, characterized in that: The system includes a refrigerant system, a hot water system, and a power supply system, wherein: The refrigerant system mainly comprises a compressor (1), a one-way valve (2), a hot water heat exchanger (3), a two-phase ejector (4), a gas-liquid separator (5), an electronic expansion valve 1 (6), an electronic expansion valve 2 (7), a PVT array (8), a finned heat exchanger (9), a three-way valve 1 (10), a three-way valve 2 (11), and a steam ejector (12). The outlet of the compressor (1) is connected to the one-way valve (2) and the hot water heat exchanger (3) in sequence, enters the two-phase ejector (4), is ejected, and is connected to the gas-liquid separator (5), and then is divided into two paths, one of which is separated from the top of the gas-liquid separator (5) and connected to the inlet of the compressor (1), and the other is separated from the bottom of the gas-liquid separator (5) and is further divided into two paths. One path: after passing through the electronic expansion valve one (6) and the PVT array (8), it is divided into two paths again, one path is connected to the high-pressure inlet end of the steam injector (12) through the three-way valve one (10), and the other path is connected to the low-pressure inlet end of the steam injector (12) through the three-way valve two (11); another path separated from the bottom end of the gas-liquid separator (5): after passing through the electronic expansion valve two (7) and the fin-type heat exchanger (9), it is divided into two paths again, one path is connected to the high-pressure inlet end of the steam injector (12) through the three-way valve one (10), and the other path is connected to the low-pressure inlet end of the steam injector (12) through the three-way valve two (11); the steam injector (12) is connected to the low-pressure inlet end of the two-phase injector (4); The hot water system is mainly composed of a hot water heat exchanger (3) and a water pump (13), and the water side of the hot water heat exchanger (3) is connected to the water pump (13) via a water pipeline; The power supply system is mainly composed of a PVT array (8), a DC converter (14), a municipal power grid (15), and an AC / DC inverter (16). The power supply system is divided into two routes, one route connecting the PVT array (8) with the DC converter (14), and the other route connecting the municipal power grid (15) with the AC / DC inverter (16). The two routes are connected to the compressor (1), the fan of the finned heat exchanger (9), and the water pump (13) after being combined.

2. The double-injection efficiency-enhanced solar PVT-air source coupled heat pump cogeneration system according to claim 1 is characterized in that: By controlling the opening and closing of the compressor (1), the electronic expansion valve 1 (6), the electronic expansion valve 2 (7), the fan of the finned heat exchanger (9), the three-way valve 1 (10), the three-way valve 2 (11), and the water pump (13), the system can realize the switching between the following two operation modes: Mode 1: the compressor (1), the electronic expansion valve 1 (6), the electronic expansion valve 2 (7), the fan of the finned heat exchanger (9), the three-way valve 1 (10), and the water pump (13) are turned on, and the system operates in a coupled heat pump cogeneration mode with solar energy as the main heat source and air energy as the auxiliary heat source; Mode 2: The compressor (1), the electronic expansion valve 1 (6), the electronic expansion valve 2 (7), the fan of the finned heat exchanger (9), the three-way valve 2 (11), and the water pump (13) are turned on, and the system operates in a coupled heat pump cogeneration mode with air energy as the main heat source and solar energy as the auxiliary heat source.

3. The double-injection efficiency-enhanced solar PVT-air source coupled heat pump cogeneration system according to claim 1 or 2, characterized in that: The types of compressors (1) include rotor type, scroll type and piston type.

4. The double-injection efficiency-enhanced solar PVT-air source coupled heat pump cogeneration system according to claim 1 is characterized in that: The types of the hot water heat exchanger (3) include flat plate type, spiral plate type, plate fin type, immersed spiral tube type, sleeve type, and shell and tube type.

5. The double-injection efficiency-enhanced solar PVT-air source coupled heat pump cogeneration system according to claim 1 or 2, characterized in that: The electronic expansion valve 1 (6) and the electronic expansion valve 2 (7) can be replaced by a thermal expansion valve or a capillary tube.

6. The double-injection efficiency-enhanced solar PVT-air source coupled heat pump cogeneration system according to claim 1 is characterized in that: The types of solar cell elements of the PVT array (8) include single crystal silicon, polycrystalline silicon, copper indium gallium selenide, gallium arsenide, cadmium telluride, and perovskite.

7. The double-injection efficiency-enhanced solar PVT-air source coupled 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, water drop, and honeycomb.

8. The double-injection efficiency-enhanced solar PVT-air source coupled heat pump cogeneration system according to claim 1 or 2, characterized in that: The motors of the compressor (1), the fan of the finned heat exchanger (9), and the water pump (13) are all DC-driven, and their types include brushless DC, brushed DC, and permanent magnet DC.

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