Solar PVT-air energy injection-compression composite heat pump combined heat and power generation system

Abstract

The invention relates to a solar PVT-air energy injection-compression combined 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 water pump, a direct-current converter, a municipal power grid and an alternating-current and direct-current inverter, and cogeneration is achieved. The utilization rate of renewable energy solar energy and air energy is high, solar energy and air energy complement each other, and system energy supply is stable; the jet refrigeration technology and the multi-source heat pump technology are integrated, throttling loss and overheating loss in a traditional heat pump can be greatly reduced, the system is energy-saving, efficient, green and low-carbon, construction of a clean and low-carbon society is assisted, and sustainable development of energy is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of solar photovoltaic-air energy heat pump, in particular to a solar PVT-air energy injection-compression composite heat pump cogeneration system. Technical Background

[0002] Solar energy has been widely used around the world for its high quality, cleanliness, safety, large quantity and wide application. In recent years, photovoltaic thermal (PVT) heat pump technology has effectively integrated photovoltaic technology, thermal technology and heat pump technology, reducing the temperature of photovoltaic cells and improving the efficiency of photovoltaic power generation. At the same time, it can improve the comprehensive utilization rate of solar energy and achieve cogeneration of heat and power. However, due to the strong periodicity, poor stability, low and uneven energy density of solar energy, the production capacity stability of PVT heat pump system is poor, and it is difficult to achieve continuous and stable energy output, which limits the large-scale promotion and 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 sources such as solar energy and air energy as the heat source of the system, relying on jet refrigeration technology, solar PVT technology, and multi-energy complementary heat pump technology to improve the production capacity stability of the solar PVT heat pump system, reduce its operating energy consumption, and improve its operating performance, thereby facilitating the large-scale promotion and application of solar PVT heat pump technology.

[0004] To achieve the above-mentioned object, the present invention provides a solar PVT-air energy injection-compression composite 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 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, and a finned heat exchanger 9. The outlet of the compressor 1 is connected to the one-way valve 2, the hot water heat exchanger 3, the two-phase ejector 4, and the gas-liquid separator 5 in sequence, and two paths are separated through the gas-liquid separator 5. One path is separated from the top of the gas-liquid separator 5 and connected to the inlet of the compressor 1; the other path is separated from the bottom of the gas-liquid separator 5. One path is connected to the electronic expansion valve 1 6 and the PVT array 8 in sequence, and the other path is connected to the electronic expansion valve 2 7 and the finned heat exchanger 9 in sequence. The above two paths are connected to the low-pressure inlet of the two-phase ejector 4 after being combined through the outlet of the PVT array 8 and the outlet of the finned heat exchanger 9;

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

[0007] The 3 types of hot water heat exchangers include flat plate, spiral plate, plate fin, immersed spiral tube, sleeve and tube, and shell and tube;

[0008] Electronic expansion valve 1 6 and electronic expansion valve 2 7 can be replaced by thermal expansion valve and 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 hot water heat exchanger 3 and a water pump 10. The water pump 10 is connected to the water side of the hot water heat exchanger 3 via a water pipeline.

[0011] The power supply system mainly consists of a PVT array 8, a DC converter 11, a municipal power grid 12, and an AC / DC inverter 13. The power supply system is divided into two routes, one route is connected to the PVT array 8 and the DC converter 11, and the other route is connected to the municipal power grid 12 and the AC / DC inverter 13. The above two routes are connected to the compressor 1, the fan of the finned heat exchanger 9, and the water pump 10 after being combined through the outlet of the DC converter 11 and the outlet of the AC / DC inverter 13;

[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, the fan of the finned heat exchanger 9 and the water pump 10 are DC driven, and their types include brushless DC, brushed DC and permanent magnet DC.

[0014] By controlling the compressor 1, the electronic expansion valve 1 6, the electronic expansion valve 2 7, the fan of the finned heat exchanger 9, and the water pump 10, the system can switch between the following three operating modes:

[0015] Mode 1, compressor 1, electronic expansion valve 16, and water pump 10 are turned on, and the system operates in solar PVT injection-compression composite heat pump cogeneration mode;

[0016] Mode 2, compressor 1, electronic expansion valve 2 7, fan of finned heat exchanger 9, and water pump 10 are turned on, and the system operates in air energy injection-compression composite heat pump cogeneration mode;

[0017] Mode three, compressor 1, electronic expansion valve one 6, electronic expansion valve two 7, fan of finned heat exchanger 9, and water pump 10 are turned on, and the system operates in solar PVT-air energy injection-compression composite heat pump cogeneration mode.

[0018] Beneficial effects of the present invention:

[0019] The present invention makes full use of renewable energy sources, such as solar energy and air energy, which not only improves the comprehensive utilization rate of solar energy, but also improves the application rate of renewable energy in the system;

[0020] The present invention realizes the complementarity between solar energy and air energy, and the system has high energy supply stability;

[0021] The present invention combines the jet refrigeration technology with the multi-source heat pump technology, improves the thermodynamic cycle process, greatly reduces the throttling loss and overheating loss of the traditional steam compression cycle, and improves the compressor efficiency and system performance;

[0022] The system of the present invention generates and uses electric energy by itself, and the system is highly efficient, energy-saving, low-carbon and has low operating costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of a solar PVT-air energy injection-compression composite heat pump cogeneration system of the present invention;

[0024] Figure 2 This is a schematic diagram of the heat and power cogeneration mode of the solar PVT injection-compression composite heat pump of the present invention;

[0025] Figure 3 This is a schematic diagram of the cogeneration mode of the air energy injection-compression composite heat pump 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-fin heat exchanger, 10-water pump, 11-DC converter, 12-municipal power grid, 13-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 solar PVT-air energy injection-compression composite 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, and a finned heat exchanger 9 connected via a refrigerant pipeline;

[0030] The hot water system is mainly composed of a hot water heat exchanger 3 and a water pump 10 connected via a water pipeline;

[0031] The power supply system mainly consists of a PVT array 8, a DC converter 11, a municipal power grid 12, and an AC / DC inverter 13 connected via circuits.

[0032] In this embodiment, by controlling the compressor 1, the electronic expansion valve 1 6, the electronic expansion valve 2 7, the fan of the finned heat exchanger 9, and the start and stop of the water pump 10, the system can realize the switching of the solar PVT injection-compression composite heat pump cogeneration mode, the air energy injection-compression composite heat pump cogeneration mode, and the solar PVT-air energy injection-compression composite heat pump cogeneration mode.

[0033] (1) When the outdoor solar radiation intensity is high and the ambient temperature is low, the system operates in the solar PVT injection-compression composite heat pump cogeneration mode, and the compressor 1, the electronic expansion valve 6, and the water pump 10 are turned on. Figure 2 As shown, the working principle is as follows: low-temperature and low-pressure gaseous refrigerant is compressed by compressor 1 into high-temperature and high-pressure gaseous refrigerant, enters hot water heat exchanger 3 through one-way valve 2 to release heat into the hot water system, and high-temperature and high-pressure gaseous refrigerant is then condensed into medium-temperature and high-pressure liquid refrigerant, and then enters two-phase ejector 4 to inject low-pressure gas to become medium-pressure gas-liquid two-phase refrigerant, and then is separated into saturated gaseous refrigerant and saturated liquid refrigerant through gas-liquid separator 5, wherein saturated gaseous refrigerant returns to compressor 1; saturated liquid refrigerant is throttled and depressurized by electronic expansion valve 16 to become gas-liquid two-phase refrigerant, and then enters PVT array 8 to absorb solar energy and air energy to boil into gaseous refrigerant, and then enters low-pressure inlet of two-phase ejector 4. Driven by water pump 10, hot water enters hot water heat exchanger 3 to absorb heat, and is continuously heated in this cycle. In addition, the solar cells of the PVT array 8 convert solar energy into DC power, and convert it into DC 750V through the DC converter 11 for use in the system DC equipment. 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 13; if the power generated by the PVT array 8 is less than the power consumption of the system, the grid is converted into DC 750V through the AC-DC inverter 13 for use in the system DC equipment.

[0034] (2) When the outdoor solar radiation intensity is low and the ambient temperature is high, the air energy injection-compression composite heat pump operates in the cogeneration mode, and the compressor 1, the electronic expansion valve 2 7, the finned heat exchanger 9 fan, and the water pump 10 are turned on. Figure 3As shown, the working principle is as follows: low-temperature and low-pressure gaseous refrigerant is compressed by compressor 1 into high-temperature and high-pressure gaseous refrigerant, enters hot water heat exchanger 3 through one-way valve 2 to release heat into the hot water system, and high-temperature and high-pressure gaseous refrigerant is then condensed into medium-temperature and high-pressure liquid refrigerant, and then enters two-phase ejector 4 to inject low-pressure gas to become medium-pressure gas-liquid two-phase refrigerant, and then is separated into saturated gaseous refrigerant and saturated liquid refrigerant through gas-liquid separator 5, wherein saturated gaseous refrigerant returns to compressor 1; saturated liquid refrigerant is throttled and depressurized by electronic expansion valve 27 to become gas-liquid two-phase refrigerant, and then enters finned heat exchanger 9 to absorb air energy and boil into gaseous refrigerant, and then enters low-pressure inlet of two-phase ejector 4. Driven by water pump 10, hot water enters hot water heat exchanger 3 to absorb heat, and is continuously heated in this cycle. In addition, the solar cells of the PVT array 8 convert solar energy into DC power, and convert it into DC 750V through the DC converter 11 for use in the system DC equipment. 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 13; if the power generated by the PVT array 8 is less than the power consumption of the system, the grid is converted into DC 750V through the AC-DC inverter 13 for use in the system DC equipment.

[0035] (3) When the outdoor solar radiation intensity and ambient temperature are both high or low, the system operates in the solar PVT-air energy injection-compression composite heat pump cogeneration mode, and the compressor 1, the electronic expansion valve 1 6, the electronic expansion valve 2 7, the fan of the finned heat exchanger 9, and the water pump 10 are turned on. Figure 1 As 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 gas and become a medium-pressure gas-liquid two-phase refrigerant, and then passes through the gas-liquid separator 5 to separate into saturated gaseous refrigerant and saturated liquid refrigerant, wherein the saturated gaseous refrigerant returns to the compressor 1; the saturated liquid refrigerant passes through the electronic expansion valve 1 6 for throttling and pressure reduction to become a gas-liquid two-phase refrigerant, and then enters the PVT array 8 to absorb solar energy and air energy to boil into a gaseous refrigerant; the other path passes through the electronic expansion valve 2 7 for throttling and pressure reduction to become a gas-liquid two-phase refrigerant, and then enters the finned heat exchanger 9 to absorb air energy to boil into a gaseous refrigerant, and the above two paths of gaseous refrigerants merge and enter the low-pressure inlet of the two-phase ejector 4. Driven by the water pump 10, the hot water enters the hot water heat exchanger 3 to absorb heat, and is continuously heated in this cycle. In addition, the PVT array 8 cells convert solar energy into DC power, and convert it into DC 750V through the DC converter 11 for the system DC equipment. If the power generated by the PVT array 8 is greater than the system power consumption, the surplus power is connected to the grid through the AC-DC inverter 13; if the power generated by the PVT array 8 is less than the system power consumption, the grid is converted into DC 750V through the AC-DC inverter 13 for the system DC equipment.

[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 solar PVT-air energy injection-compression composite heat pump cogeneration system, the system includes a refrigerant system, a hot water system, and a power supply system; 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), and a finned heat exchanger (9). The outlet of the compressor (1) is connected to the one-way valve (2), the hot water heat exchanger (3), the two-phase ejector (4), and the gas-liquid separator (5) in sequence. Two paths are separated through the gas-liquid separator (5). One path is separated from the top of the gas-liquid separator (5) and connected to the inlet of the compressor (1). The other path is separated from the bottom of the gas-liquid separator (5). One path is connected to the electronic expansion valve 1 (6) and the PVT array (8) in sequence, and the other path is connected to the electronic expansion valve 2 (7) and the finned heat exchanger (9) in sequence. The above two paths are connected to the low-pressure inlet of the two-phase ejector (4) after being combined through the outlet of the PVT array (8) and the outlet of the finned heat exchanger (9). The hot water system is mainly composed of a hot water heat exchanger (3) and a water pump (10), and the water pump (10) is connected to the water side of the hot water heat exchanger (3) via a water pipeline; The power supply system is mainly composed of a PVT array (8), a DC converter (11), a municipal power grid (12), and an AC / DC inverter (13). The power supply system is divided into two routes, one route is connected between the PVT array (8) and the DC converter (11), and the other route is connected between the municipal power grid (12) and the AC / DC inverter (13). The two routes are connected to the compressor (1), the fan of the finned heat exchanger (9), and the water pump (10) after being combined through the outlet of the DC converter (11) and the outlet of the AC / DC inverter (13).

2. The solar PVT-air energy injection-compression composite heat pump cogeneration system according to claim 1 is characterized in that: By controlling the compressor (1), the electronic expansion valve 1 (6), the electronic expansion valve 2 (7), the fan of the finned heat exchanger (9), and the water pump (10) to start and stop, the system can switch between the following three operating modes: Mode 1: the compressor (1), the electronic expansion valve 1 (6), and the water pump (10) are turned on, and the system operates in a solar PVT injection-compression composite heat pump cogeneration mode; Mode 2: the compressor (1), the second electronic expansion valve (7), the fan of the finned heat exchanger (9), and the water pump (10) are turned on, and the system operates in an air energy injection-compression composite heat pump cogeneration mode; Mode three: the compressor (1), the electronic expansion valve 1 (6), the electronic expansion valve 2 (7), the fan of the finned heat exchanger (9), and the water pump (10) are turned on, and the system operates in a solar PVT-air energy injection-compression composite heat pump cogeneration mode.

3. The solar PVT-air energy injection-compression composite 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 solar PVT-air energy injection-compression composite heat pump cogeneration system according to claim 1 is characterized in that: The types of hot water heat exchangers (3) include flat plate type, spiral plate type, plate fin type, immersed spiral tube type, sleeve type, and shell and tube type.

5. The solar PVT-air energy injection-compression composite 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 solar PVT-air energy injection-compression composite 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.

7. The solar PVT-air energy injection-compression composite heat pump cogeneration system according to claim 1 is characterized by: 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 solar PVT-air energy injection-compression composite 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 (10) are DC-driven, and their types include brushless DC, brushed DC, and permanent magnet DC.

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