Double-injection efficiency-enhanced solar PVT-air source coupled heat pump cogeneration system

Abstract

The present invention relates to a dual-injection efficiency-enhancing solar PVT-air source coupled heat pump cogeneration system. The system includes 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, an electronic expansion valve 1, an electronic expansion valve 2, a PVT array, a fin heat exchanger, a three-way valve 1, a three-way valve 2, a steam ejector, a water pump, a DC converter, a municipal power grid, and an AC / DC inverter. The system can achieve the synchronous output of heat energy and electrical energy. The system of the embodiment of the present invention can achieve dual evaporation temperatures, and can freely switch between the main heat source and the auxiliary heat source of the system according to the heat source conditions of outdoor solar energy and air energy, realize multi-energy complementarity, and provide reliable and stable energy supply for the system. The embodiment of the present invention utilizes dual-injection technology to effectively reduce throttling losses and overheating losses in traditional steam compression heat pump systems. The system is energy-saving, efficient, green, low-carbon, has low operating costs, and has promotional and application value.

Description

Technical Field

[0001] The present invention belongs to the technical field of solar photovoltaic thermal-air energy heat pumps, and 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, primarily utilized through photovoltaic and thermal energy utilization. Photovoltaic thermal (PVT) heat pump technology integrates photovoltaic, thermal, and heat pump technologies, lowering the surface temperature of photovoltaic cells and improving photovoltaic power generation efficiency while simultaneously increasing the overall utilization rate of solar energy and achieving cogeneration. However, due to the periodicity, intermittency, and low and uneven energy density of solar energy, the production capacity of PVT heat pump technology is relatively unstable, making it difficult to achieve sustained and stable energy output, thus limiting its large-scale application. Therefore, there is an urgent need to explore multi-source, stable, and efficient heat pump technology paths that complement the renewable energy of solar energy. Summary of the Invention

[0003] In response to 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 objectives, an embodiment of the present invention provides a dual-injection efficiency-enhancing 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 mainly consists 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, enters the two-phase ejector and is connected to the gas-liquid separator after injection, and then splits into two paths. One path is separated from the top of the gas-liquid separator and connected to the compressor inlet, and the other path is split 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 split into two paths again. One path is connected to the high-pressure inlet of the steam ejector through the three-way valve 1, and the other path is connected to the low-pressure inlet of the steam ejector through the three-way valve 2. The other path separated from the bottom end of the gas-liquid separator: after passing through the electronic expansion valve 2 and the finned heat exchanger, it is split into two paths again. One path is connected to the high-pressure inlet of the steam ejector through the three-way valve 1, and the other path is connected to the low-pressure inlet of the steam ejector through the three-way valve 2. The steam ejector is connected to the low-pressure inlet of the two-phase ejector.

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

[0007] Hot water heat exchanger types 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 mainly consists 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 connects the PVT array to the DC converter, and the other route connects the municipal power grid to 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 the finned heat exchanger, three-way valve 1, three-way valve 2, and the opening and closing of the water pump, the system can switch between the following two operating modes:

[0015] Mode 1: The compressor, electronic expansion valve 1, electronic expansion valve 2, fan of the finned heat exchanger, three-way valve 1, and water pump are turned on. 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 renewable energy sources such as solar energy and air energy, and the system has a high renewable energy utilization rate;

[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, with high utilization rate of low-grade heat source;

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

[0021] The embodiments of the present invention can combine ejector refrigeration technology with multi-source coupled heat pump technology, thereby improving the thermodynamic cycle process, significantly reducing throttling losses and superheating losses in the traditional vapor compression cycle process, and improving 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 efficient, energy-saving, low-carbon, and has low operating costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is 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 This is a schematic diagram of the principle of a 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 This is a schematic diagram of the principle of a coupled heat pump cogeneration mode using 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 1, 7-electronic expansion valve 2, 8-PVT array, 9-finned heat exchanger, 10-three-way valve 1, 11-three-way valve 2, 12-steam ejector, 13-water pump, 14-DC converter, 15-municipal power grid, 16-AC / DC inverter. DETAILED DESCRIPTION

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0028] like Figure 1 As shown, in this embodiment, a double-injection efficiency-enhancing 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 mainly consists 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, which are connected via refrigerant pipelines.

[0030] The hot water system mainly consists 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 switching between a coupled heat pump cogeneration mode with solar energy as the main heat source and air energy as the auxiliary heat source and a 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, the fan of the finned heat exchanger 9, the three-way valve 10, and the 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 then 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 ways One path is throttled and reduced in pressure by electronic expansion valve 16 to form a gas-liquid two-phase refrigerant. It then enters PVT array 8, where it absorbs the primary heat source—solar energy—to form a superheated gaseous refrigerant. This gaseous refrigerant then enters the high-pressure inlet of steam ejector 12 through three-way valve 10. The other path is throttled and reduced in pressure by electronic expansion valve 27 (with a greater degree of throttling than the previous path) to form a gas-liquid two-phase refrigerant. It then enters finned heat exchanger 9, where it absorbs auxiliary heat source—air energy—to form a superheated gaseous refrigerant. This gaseous refrigerant then enters the low-pressure inlet of steam ejector 12 through three-way valve 21 and is ejected. Driven by water pump 13, hot water enters hot water heat exchanger 3, where it absorbs heat, continuing this cycle and heating. Furthermore, PVT array 8 converts solar energy into DC electricity, which is then converted to a specific DC voltage by DC converter 14 for system use. If the power generated by PVT array 8 exceeds the system's consumption, the excess power is fed to the grid via AC / DC inverter 16. If the power generated by PVT array 8 is less than the system's consumption, the grid is converted to a specific DC voltage by AC / DC inverter 16 for system use.

[0034] (2) When the solar heat source is inferior to the air 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 then 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 ways One path is throttled and reduced in pressure by electronic expansion valve 16 to form a gas-liquid two-phase refrigerant. It then enters PVT array 8, absorbing the auxiliary heat source—solar energy—to form a superheated gaseous refrigerant. This is then ejected through three-way valve 2 (11) into the low-pressure inlet of steam ejector 12. The other path is throttled and reduced in pressure by electronic expansion valve 2 (7) (the degree of throttling is less than the previous path) to form a gas-liquid two-phase refrigerant. It then enters finned heat exchanger 9, absorbing the primary heat source—air energy—to form a superheated gaseous refrigerant. It then enters the high-pressure inlet of steam ejector 12 through three-way valve 10. Driven by water pump 13, hot water enters hot water heat exchanger 3, absorbing heat, and continues the cycle, heating the system. Furthermore, PVT array 8 converts solar energy into DC electricity, which is then converted to a specific DC voltage by DC converter 14 for system use. If the power generated by PVT array 8 exceeds the system's consumption, the excess power is fed to the grid via AC / DC inverter 16. If the power generated by PVT array 8 is less than the system's consumption, the grid is converted to a specific DC voltage by AC / DC inverter 16 for system use.

[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. By reducing the frequency of the fan of the finned heat exchanger 9, high-pressure superheated gaseous refrigerant is provided 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, electronic expansion valve 1 6, electronic expansion valve 2 7, fan of the finned heat exchanger 9, three-way valve 2 11, and water pump 13 are turned on. At this time, if Figure 3 As shown, the working principle is as described in (2).

[0036] While 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 these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A dual-injection efficiency-enhancing 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 consists 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 (10), a three-way valve (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 then is connected to the gas-liquid separator (5), and then splits into two paths, one of which is split from the top of the gas-liquid separator (5) and connected to the inlet of the compressor (1), and the other is split into two paths from the bottom of the gas-liquid separator (5). One path: after passing through the electronic expansion valve 1 (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 ejector (12) through the three-way valve 1 (10), and the other path is connected to the low-pressure inlet end of the steam ejector (12) through the three-way valve 2 (11); the other path separated from the bottom end of the gas-liquid separator (5): after passing through the electronic expansion valve 2 (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 ejector (12) through the three-way valve 1 (10), and the other path is connected to the low-pressure inlet end of the steam ejector (12) through the three-way valve 2 (11); the outlet end of the steam ejector (12) is connected to the low-pressure inlet end of the two-phase ejector (4); The hot water system mainly consists 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 mainly consists 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 combined and connected to the compressor (1), the fan of the finned heat exchanger (9), and the water pump (13).

2. The dual-injection efficiency-enhancing 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 operating 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; In 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 dual-injection efficiency-enhancing solar PVT-air source coupled heat pump cogeneration system according to claim 1 or 2, characterized in that: The types of the compressor (1) include rotor type, scroll type and piston type.

4. The dual-injection efficiency-enhancing 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 rib type, immersed spiral tube type, sleeve type, and shell and tube type.

5. The dual-injection efficiency-enhancing 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 dual-injection efficiency-enhancing solar PVT-air source coupled heat pump cogeneration system according to claim 1, 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 dual-injection efficiency-enhancing solar PVT-air source coupled heat pump cogeneration system according to claim 1, 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.

8. The dual-injection efficiency-enhancing 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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