CN114646151A - Combined cooling heating and power PVT direct-current heat pump system and operation method - Google Patents

Abstract

The invention relates to a cold and hot electricity PVT direct current heat pump trigeminy supplies system, including: the heat and cold combined supply PVT direct-current heat pump system comprises a plate evaporator, an outdoor air-cooled evaporator, an indoor air-cooled evaporator, a direct-current variable-frequency compressor, a condenser and a heat preservation water tank; the direct-current variable-frequency compressor and the condenser are connected to form a main path, and the plate evaporator, the outdoor air-cooled evaporator and the indoor air-cooled evaporator are respectively connected with the main path in series to form a first heat pump working medium loop, a second heat pump working medium loop and a third heat pump working medium loop; the solar photovoltaic photo-thermal system comprises a photovoltaic module heat collector; the plate-type evaporator is connected with the heat exchange medium side of the photovoltaic module heat collector in series to form a medium loop. The operating method is characterized in that the on-off of the medium loop and the heat pump working medium loop is controlled by judging the temperature difference between the heat exchange medium temperature of the photovoltaic module heat collector and the ambient temperature. The invention utilizes the solar energy and air energy to operate and improve the performance, and simultaneously solves the domestic hot water requirement, the cold quantity requirement and the electricity utilization requirement of a low-power electric appliance.

Description

A kind of cooling, heating and electricity PVT DC heat pump triple supply system and operation method

technical field

The invention relates to the technical field of heat pump hot water production, in particular to a cold-heat-electricity PVT direct-current heat pump triple supply system and an operation method.

Background technique

Air source heat pump is an energy-saving device that utilizes high-level energy to transfer heat from low-level heat source air to high-level heat source. The technical performance of the air source heat pump mainly depends on the temperature of the air in the environment and the heat exchange efficiency of the system. Through the four-way reversing valve, it can generally have two modes of cooling and heating. The main advantages of the air source heat pump technology are: the air source is convenient and easy to obtain, inexhaustible and inexhaustible; no cooling water system is required, and the installation and use are simple; it does not cause pollution to the environment. However, the system performance is greatly affected by the ambient temperature, and it relies on the high-level energy such as electricity to drive the heat pump.

Solar photovoltaic power generation technology is based on the principle of photovoltaic effect, using solar cells to directly convert sunlight energy into electrical energy. The electric energy generated by solar cells can be used independently or connected to the grid to generate electricity. The whole process has the characteristics of energy saving, environmental protection and good economy. Solar photovoltaic technology relies on sunlight conditions, so it generally needs to be used outdoors. On this basis, solar photovoltaic photothermal comprehensive utilization technology (PVT) can collect solar thermal energy while using solar energy to generate electricity, and further improve the utilization efficiency of solar energy. Using solar energy to produce hot water is a convenient and convenient method.

The invention patent with publication number CN 201721042232.9 discloses a combined cooling and heating device driven by natural gas. Although combined cooling and heating can also be performed, the system needs to burn natural gas when supplying heat, so the operating cost is significantly higher, and a greenhouse is generated at the same time. Gas is not energy-saving and environmentally friendly. In addition, this system is suitable for indoor use, which is not convenient for outdoor use.

To sum up, the outdoor environment needs a combined cooling, heating and power supply system that can supply electricity, make hot water, have good cooling effect, good energy saving, good economy, good practicability, and no pollution to solve the problems of outdoor personnel. Electricity, cooling and domestic hot water needs.

SUMMARY OF THE INVENTION

Aiming at the deficiencies of the prior art, the present invention provides a combined cooling, heating and electricity PVT DC heat pump triple supply system and an operation method, with the purpose of ensuring that the system can meet the needs of users under various environmental conditions, and improving the flexibility and efficiency of the hot water system. reliability.

The technical scheme adopted in the present invention is as follows:

A cold-heat-electricity PVT DC heat pump triple supply system, comprising:

Combined cooling and heating PVT DC heat pump system, including plate evaporator, outdoor air-cooled evaporator, indoor air-cooled evaporator, DC inverter compressor, condenser and heat preservation water tank; the DC inverter compressor and condenser are connected to form a main circuit The plate evaporator is connected in series with the main circuit to form a first heat pump working fluid circuit, the outdoor air-cooled evaporator is connected in series with the main circuit to form a second heat pump working fluid circuit, and the indoor air-cooled evaporator and the main circuit are connected in series to form a second heat pump working fluid circuit. The circuits are connected in series to form a third heat pump working fluid circuit; the condenser is used to supply heat for the heat preservation water tank;

A solar photovoltaic photothermal system, including a photovoltaic module heat collector; the plate evaporator and the heat exchange medium side of the photovoltaic module heat collector are connected in series to form a medium loop; the solar photovoltaic photothermal system is the combined cooling and heating system The PVT DC heat pump system provides DC power;

It also includes a control module, which controls the on-off of the first heat pump working fluid circuit, the second heat pump working fluid circuit and the medium circuit by judging the temperature difference between the heat exchange medium temperature of the photovoltaic module heat collector and the ambient temperature.

Further technical solutions are:

The solar photovoltaic photothermal system further includes a controller, a battery and an inverter, and the controller is used to control the power transmission side of the photovoltaic module heat collector and the battery, and the inverter, and the battery and the combined cooling and heating Electrical connections between electrical loads in PVT DC heat pump systems.

An expansion valve and an inlet valve are arranged at the inlet end of the heat pump working medium side of the plate evaporator, and an outlet valve is arranged at the outlet end; an expansion valve and an inlet valve are arranged at the inlet end of the heat pump working medium side of the outdoor air-cooled evaporator, and an outlet valve is arranged at the outlet end; An expansion valve and an inlet valve are arranged at the inlet end of the heat pump working medium side of the indoor air-cooled evaporator, and an outlet valve is arranged at the outlet end.

The inlet and outlet ends of the heat exchange medium side of the plate evaporator are respectively provided with control valves.

The outlet end of the heat exchange medium side of the photovoltaic module heat collector is connected in series with the constant pressure water tank and the first direct current water pump.

The condenser and the heat preservation water tank are connected to form a water circuit, and a second DC water pump is arranged on the water circuit, and the second DC water pump is powered by the solar photovoltaic photothermal system.

A temperature detection element is provided in the heat exchange medium side of the photovoltaic module heat collector and in the heat preservation water tank, and the control module is connected with the temperature detection element.

A method for operating the described cold-thermal-electricity PVT DC heat pump triple supply system, comprising:

In hot water mode, do the following controls:

When the temperature difference between the heat exchange medium temperature of the photovoltaic module heat collector and the ambient temperature is greater than or equal to T1, the control medium circuit is turned on, and the first heat pump working fluid circuit is kept connected while the second heat pump working fluid circuit is cut off, that is, the single solar heat source working mode is turned on. ;

When the temperature difference between the heat exchange medium temperature of the photovoltaic module heat collector and the ambient temperature is less than T1 and greater than or equal to T2, the control medium circuit is opened, and the first heat pump working fluid circuit and the second heat pump working fluid circuit are kept connected, that is, the dual heat source is turned on. model;

When the temperature difference between the heat exchange medium temperature of the photovoltaic module heat collector and the ambient temperature is less than T2, the control medium circuit is cut off, and the first heat pump working fluid circuit is kept cut off and the second heat pump working fluid circuit is turned on, that is, the single air source heat source working mode is turned on. .

Further technical solutions are:

It also includes, in the cooling mode, opening the third heat pump working fluid circuit.

The beneficial effects of the present invention are as follows:

The invention utilizes the dual heat source operation of solar energy and air energy to improve performance, and at the same time solves the domestic hot water demand, cooling demand and electricity demand of low-power electrical appliances for outdoor personnel. The present invention specifically has the following advantages:

1. Good energy saving: The whole system of electric drive from solar cells does not need additional power supplementation, and the system uses renewable energy solar energy to supply power to other electrical equipment without consuming grid power, saving energy.

2. Less loss: The use of photovoltaic direct-drive heat pump can be directly driven by the electricity generated by solar photovoltaic modules, reducing intermediate inverter losses. In addition to directly supplying power to the entire system, the electricity generated by solar photovoltaic can also meet the electricity demand of low-power electrical appliances in outdoor life.

3. High reliability: The system uses dual heat sources, and multiple operating modes improve the stability.

4. Wide range of use: off-grid operation is realized through solar photovoltaic power generation, and the transfer is convenient, so it can cope with a variety of work scenarios and is easy to use.

5. Environmentally friendly: The whole system makes full use of clean energy solar energy and air energy, does not need to use any fossil energy, and is very friendly to the environment.

Description of drawings

FIG. 1 is a schematic structural diagram of the system of the present invention.

In the figure: 1. Photovoltaic module collector; 2. Constant pressure water tank; 3. The first DC water pump; 4. Plate evaporator; 5. The first electronic expansion valve; 6. Outdoor air-cooled evaporator; 7. The first 2. Electronic expansion valve; 8. Indoor air-cooled evaporator; 9. The third electronic expansion valve; 10. DC inverter compressor; 11. Condenser; 12. Second DC water pump; 13. Insulation water tank; 14. Controller; 15, battery; 16, inverter; 17, valve one; 18, valve two; 19, valve five; 20, valve six; 21, valve seven; 22, valve eight; 23, valve three; 24, valve four.

Detailed ways

The specific embodiments of the present invention will be described below with reference to the accompanying drawings.

A cold-heat-electric PVT DC heat pump triple supply system of the present embodiment, as shown in FIG. 1 , includes:

The combined cooling and heating PVT DC heat pump system includes a plate evaporator 4, an outdoor air-cooled evaporator 6, an indoor air-cooled evaporator 8, a DC variable frequency compressor 10, a condenser 11 and a heat preservation water tank 13; among them, the DC variable frequency compressor 10 It is connected with the condenser 11 to form the main circuit, the plate evaporator 4 is connected in series with the main circuit to form the first heat pump working fluid circuit, the outdoor air-cooled evaporator 6 is connected in series with the main circuit to form the second heat pump working fluid circuit, and the indoor air-cooled evaporator 8 is connected to the main circuit. The main circuit is connected in series to form the third heat pump working fluid circuit, and the plate evaporator 4, the outdoor air-cooled evaporator 6 and the indoor air-cooled evaporator 8 are arranged in parallel; wherein, the condenser 11 is used to supply heat to the heat preservation water tank 13;

The solar photovoltaic photothermal system includes a photovoltaic component heat collector 1; wherein, the plate evaporator 4 is connected in series with the heat exchange medium side of the photovoltaic component heat collector 1 to form a medium loop.

Those skilled in the art can understand that, in order to realize the function of the circuit, each circuit is provided with necessary control valves.

The solar photovoltaic photothermal system provides DC power for the combined cooling and heating PVT DC heat pump system;

It also includes a control module, which controls the on-off of the first heat pump working fluid circuit, the second heat pump working fluid circuit and the medium circuit by judging the temperature difference between the heat exchange medium temperature of the photovoltaic module heat collector 1 and the ambient temperature.

Specifically, the photovoltaic module heat collector 1 has a heat exchange medium side and a power transmission side, and the heat exchange medium side is used for outputting the collected solar thermal energy and exchanging heat with the plate evaporator 4 . The power output on the transmission side supplies power to the combined cooling and heating PVT DC heat pump system (DC inverter compressor 10, loop valve components, etc.).

Specifically, the photovoltaic module heat collector 1 is composed of a photovoltaic module and a back heat collector. The back collector includes pipes, a mixed working medium of water and antifreeze, and thermal insulation materials. The pipeline has a small thermal conductivity and thermal resistance, which is conducive to heat transfer, and copper material with a large thermal conductivity can be used. The mixed working fluid of water and antifreeze has good thermal conductivity and also reduces the freezing point of the working fluid. An insulating material is a material with a thermal coefficient less than or equal to 0.12.

Specifically, the solar photovoltaic system further includes a controller 14 , a battery 15 and an inverter 16 . The controller 14 is used to control the distance between the transmission side of the photovoltaic module heat collector 1 and the battery 15 and the inverter 16 . And the electrical connection between the battery 15 and the electrical load of the system.

Specifically, the battery is one of a lead-acid maintenance-free battery, an ordinary lead-acid battery, and an alkaline nickel-cadmium battery.

The solar power generation system of this embodiment utilizes the photovoltaic effect to provide electrical energy for the entire combined cooling and heating PVT DC heat pump system on the one hand, and can be converted by the inverter 16 to supply power to low-power AC appliances on the other hand.

The controller 14 controls the power transmission and distribution among the photovoltaic module heat collector 1 , the storage battery 15 and the inverter 16 . When the battery 15 is in a saturated state, the controller 14 disconnects the power transmission side of the photovoltaic module heat collector 1 from the battery 15; when the battery 15 is not in a saturated state, the controller 14 opens the power transmission side of the photovoltaic module heat collector 1 Connection with the battery 15; when the load side needs electricity, the controller 14 connects the transmission side of the photovoltaic module heat collector 1 with the combined cooling and heating PVT DC heat pump system or the inverter 16; when the load side needs electricity, there is no When the solar energy or solar energy is insufficient, the controller 14 controls the battery 15 to connect with the combined cooling and heating PVT DC heat pump system or the inverter 16 . There are also manually controlled switches on the controller 14 .

Specifically, in the medium circuit formed by the plate evaporator 4 and the heat exchange medium side of the photovoltaic module heat collector 1 in series, the constant pressure water tank 2 and the first heat exchange medium side outlet end of the photovoltaic module heat collector 1 are connected in series. DC water pump 3. The constant pressure water tank 2 is used for water replenishment. The first DC water pump 3 can also be powered by a solar photovoltaic system. In the above-mentioned medium circuit, valve one 17 and valve two 18 are respectively provided at the inlet and outlet ends of the plate evaporator 4 .

When working, place the photovoltaic module collector 1 in a place with sufficient sunlight, turn on the controller 14 and the first DC water pump 3, the photovoltaic module collector 1 absorbs the solar energy and converts it into electrical energy and stores it in the battery 15 through the wire , while the battery 15 supplies power to the hot water heating system, it can also provide electrical energy for other low-power AC electrical equipment through the inverter 16 .

Specifically, the condenser 11 and the heat preservation water tank 13 are connected to form a water circuit, and a second DC water pump 12 is arranged on the water circuit, and the second DC water pump 12 can be powered by a solar photovoltaic system.

The inlet end of the heat pump working medium side of the plate evaporator 4 is provided with a first electronic expansion valve 5 and a valve six 20, and the outlet end is provided with a valve five 19; the inlet end of the heat pump working medium side of the outdoor air-cooled evaporator 6 is provided with a second electronic expansion valve 7 and a valve Eight 22, valve seven 21 is set at the outlet end; a third electronic expansion valve 9 and valve four 24 are set at the inlet end of the heat pump working medium side of the indoor air-cooled evaporator 8, and a valve three 23 is set at the outlet end.

Valve five 19, plate evaporator 4, first electronic expansion valve 5 and valve six 20 are connected in series, valve seven 21, outdoor air-cooled evaporator 6, second electronic expansion valve 7 and valve eight 22 are connected in series, valve three 23, indoor air The cold evaporator 8, the third electronic expansion valve 9 and the valve four 24 are connected in series, and the three series paths form a parallel connection, which is connected in series with the DC variable frequency compressor 10, and then connected in series with the condenser 11 to form a heat pump circuit. The entire system is DC powered.

Specifically, the condenser 11 adopts a casing type condenser.

Specifically, the heat pump working medium can be a non-azeotropic working medium.

When working, the heat pump system can be placed outdoors, and the condenser 11 transfers heat to the water to be heated in the heat preservation water tank 13 . The controller 14 is connected to the heat pump system, and controls the DC variable frequency compressor 10 through the DC drive module.

Specifically, the heat exchange medium side of the photovoltaic module heat collector 1 and the heat preservation water tank 13 are provided with temperature detection elements, and the control module is connected to the temperature detection elements.

The operation method of a cold-thermal-electricity PVT DC heat pump triple supply system of the present embodiment includes:

When the temperature difference between the heat exchange medium temperature of the photovoltaic module collector 1 and the ambient temperature is greater than or equal to T1, the medium circuit is kept open, that is, the photovoltaic module collector 1 provides heat energy to the heat pump hot water system through the plate evaporator 4 . And control the valve five 19, the valve six 20 to open, and the valve eight 22 and the valve seven 21 to close at the same time, that is, the first heat pump working fluid circuit is connected, the second heat pump working fluid circuit is cut off, and the single solar heat source working mode is maintained;

Those skilled in the art can understand that under this working condition, the thermal power of the photovoltaic module heat collector 1 is relatively high, and the user's hot water demand can be met by the single solar heat source working mode.

When the temperature difference between the temperature of the heat exchange medium of the photovoltaic module heat collector 1 and the ambient temperature is less than T1 and greater than or equal to T2, keep the medium circuit unblocked, keep the first heat pump working fluid circuit connected while the second heat pump working fluid circuit is connected, that is, open the dual heat source operation model;

During the working process, the working fluid of the heat pump becomes high temperature and high pressure steam after passing through the DC variable frequency compressor 10 , and then transfers heat to the water tank in the condenser 11 . Then enter the first electronic expansion valve 5 and the second electronic expansion valve 7 respectively, and then evaporate and absorb heat at different evaporation temperatures in the plate evaporator 4 and the outdoor air-cooled evaporator 6 respectively. After that, the two working fluids are mixed and then enter the DC inverter compressor 10 .

Those skilled in the art can understand that under this working condition, the thermal power of the photovoltaic module heat collector 1 is not high, so the dual heat source working mode needs to be turned on to meet the user's demand for hot water.

When the temperature difference between the heat exchange medium temperature of the photovoltaic module heat collector 1 and the ambient temperature is less than T2, the control medium circuit is cut off, the first heat pump working fluid circuit is cut off, and the second heat pump working fluid circuit is turned on, that is, the single air source heat source working mode is turned on.

Those skilled in the art can understand that the thermal power of the photovoltaic module heat collector 1 is low under this working condition, such as in cloudy or nighttime environments, so the user's hot water demand can only be met through the single air source heat source working mode.

Those skilled in the art can understand that T1 is greater than T2, and the specific value is set according to actual operation requirements.

In the operation method of the cold-thermal-electricity PVT DC heat pump triple supply system in this embodiment, in the cooling mode, the third heat pump working fluid circuit is opened.

Specifically, when the user uses the remote control function to turn on the cooling function, the control command has the highest priority. The heat pump is started, the valve four 24 and the valve three 23 are opened, and the indoor air-cooled evaporator 8 starts to work, that is, the third medium circuit is connected to provide cooling capacity for the room.

Specifically, by judging the temperature difference between the temperature of the heat exchange medium of the photovoltaic module heat collector 1 and the ambient temperature, at least one of the branch where the solar panel evaporator 4 is located and the outdoor air evaporator 6 are controlled to be in the passage, so that the solar energy is used as the heat source and the air As the heat source of the solar photovoltaic photothermal system, the heat preservation water tank 13 is heated by at least one heat source of the solar heat energy absorbed by the photovoltaic module collector 1 and the air heat energy absorbed by the outdoor air evaporator 6 . The opening and closing of the indoor evaporator 8 depends on the user's manual remote control.

The application uses two heat pump circuits to meet the demand for hot water under different ambient temperature conditions, and has the functions of refrigeration and power supply at the same time, and has the advantages of good energy saving, practical system, reliable performance, and good economy. It can meet the needs of outdoor small and medium-sized Hot water required.

The above-mentioned specific embodiments are preferred embodiments of the present invention, and do not limit the present invention. Any other changes or other equivalent substitutions without departing from the technical solutions of the present invention are included within the protection scope of the present invention.

Claims (9)

1. The utility model provides a cold and hot electricity PVT direct current heat pump trigeminy supplies system which characterized in that includes:

the cold and heat combined supply PVT direct-current heat pump system comprises a plate evaporator (4), an outdoor air-cooled evaporator (6), an indoor air-cooled evaporator (8), a direct-current variable-frequency compressor (10), a condenser (11) and a heat-preservation water tank (13); the direct-current variable-frequency compressor (10) and the condenser (11) are connected to form a main path, the plate-type evaporator (4) and the main path are connected in series to form a first heat pump working medium loop, the outdoor air-cooled evaporator (6) and the main path are connected in series to form a second heat pump working medium loop, and the indoor air-cooled evaporator (8) and the main path are connected in series to form a third heat pump working medium loop; the condenser (11) is used for supplying heat to the heat-preservation water tank (13);

the solar photovoltaic photo-thermal system comprises a photovoltaic module heat collector (1); the plate-type evaporator (4) is connected with the heat exchange medium side of the photovoltaic module heat collector (1) in series to form a medium loop; the solar photovoltaic photo-thermal system provides direct current for the cold and heat co-generation PVT direct current heat pump system;

the control module controls the on-off of the first heat pump working medium loop, the second heat pump working medium loop and the medium loop by judging the temperature difference between the heat exchange medium temperature of the photovoltaic assembly heat collector (1) and the ambient temperature.

2. The combined cooling, heating and power PVT direct current heat pump system as claimed in claim 1, wherein the solar photovoltaic photo-thermal system further comprises a controller (14), a storage battery (15) and an inverter (16), the controller (14) is used for controlling the electric connection between the power transmission side of the photovoltaic module heat collector (1) and the storage battery (15), between the inverter (16) and between the storage battery (15) and the electric load of the combined cooling, heating and power PVT direct current heat pump system.

3. The combined cooling, heating and power PVT direct-current heat pump system as claimed in claim 1, wherein an expansion valve and an inlet valve are arranged at the inlet end of the heat pump working medium side of the plate evaporator (4), and an outlet valve is arranged at the outlet end; an expansion valve and an inlet valve are arranged at the inlet end of the working medium side of the heat pump of the outdoor air-cooled evaporator (6), and an outlet valve is arranged at the outlet end; an expansion valve and an inlet valve are arranged at the inlet end of the working medium side of the heat pump of the indoor air-cooled evaporator (8), and an outlet valve is arranged at the outlet end.

4. The combined cooling, heating and PVT direct current heat pump system of claim 1, wherein the plate evaporator (4) has control valves at the inlet and outlet of the heat transfer medium.

5. The combined cooling, heating and power PVT direct-current heat pump system as claimed in claim 1, wherein the outlet end of the heat exchange medium side of the photovoltaic module heat collector (1) is connected in series with the constant-pressure water tank (2) and the first direct-current water pump (3).

6. The combined cooling, heating and power PVT direct current heat pump system as claimed in claim 1, wherein the condenser (11) and the holding water tank (13) are connected to form a water loop, a second direct current water pump (12) is arranged on the water loop, and the second direct current water pump (12) is powered by the solar photovoltaic photo-thermal system.

7. The combined cooling, heating and power PVT direct current heat pump system as claimed in claim 1, wherein the heat exchange medium side of the photovoltaic module heat collector (1) and the heat preservation water tank (13) are both provided with temperature detection elements, and the control module is connected with the temperature detection elements.

8. A method for operating a combined cooling, heating and PVT direct current heat pump system as claimed in claim 1, comprising:

in the hot water making mode, the following control is carried out:

when the temperature difference between the heat exchange medium temperature of the photovoltaic module heat collector (1) and the environment temperature is greater than or equal to T1, a medium loop is controlled to be opened, the first heat pump working medium loop is kept communicated, and the second heat pump working medium loop is cut off, namely, a single solar heat source working mode is started;

when the temperature difference between the heat exchange medium temperature of the photovoltaic module heat collector (1) and the environment temperature is smaller than T1 and is larger than or equal to T2, the medium loop is controlled to be opened, the first heat pump working medium loop and the second heat pump working medium loop are communicated, and the double-heat-source working mode is started;

when the temperature difference between the heat exchange medium temperature of the photovoltaic module heat collector (1) and the environment temperature is smaller than T2, the medium loop is controlled to be cut off, the first heat pump working medium loop is kept to be cut off, the second heat pump working medium loop is kept to be opened, and the single air source heat source working mode is started.

9. The method of operating a combined cooling, heating and PVT, dc heat pump system of claim 8, further comprising, in a cooling mode, turning on the third heat pump working medium circuit.

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