Composite heliostat based on photovoltaic power generation and photo-thermal power generation system

Abstract

The utility model relates to a composite heliostat based on photovoltaic power generation and a photo-thermal power generation system, and belongs to the technical field of heliostats, the composite heliostat comprises a heliostat body, a photovoltaic cell panel, a truss and a stand column; the multiple heliostat bodies are arranged at the upper end of the truss in an array mode to form a heliostat structure. The heliostat structure is used for reflecting and concentrating sunlight to the heat collector; the heat collector is connected with the generator, and the generator generates electricity through solar thermal energy. The photovoltaic cell panel at one end of the heliostat structure is mounted on the truss for photovoltaic power generation; the center of the bottom end of the truss is installed at the top end of the stand column. The photovoltaic cell panel is connected with a station service electric circuit through a cable and supplies power to station service electric equipment. According to the utility model, the station service power supply of the photo-thermal power generation system is satisfied through photovoltaic power generation, the necessary power supply of key equipment can be ensured during power failure without independently configuring an emergency standby power supply system, and the overall investment of the photo-thermal power generation system is also reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of heliostats, and in particular to a composite heliostat and photothermal power generation system based on photovoltaic power generation. Background Art

[0002] Solar thermal power generation is a method of generating electricity using solar energy. It collects sunlight by concentrating it on a collector through a large array of heliostats. The collected heat energy is converted into steam through a heat exchange device, and then combined with the process of traditional steam turbine generators to generate electricity.

[0003] Heliostats play a focusing role in the entire solar thermal system, concentrating scattered solar energy to one point, allowing the collector to reach a higher temperature in a shorter time, thereby improving the thermal efficiency of the entire solar thermal power generation system.

[0004] The operation of CSP requires a portion of electricity to ensure the operation of the power station itself (i.e., power consumption), and the remaining power is fed into the grid to generate economic benefits. Power consumption is mainly used to support key operations of the power station, such as the operation of rotating equipment, tracking and adjustment of the heat collection system, maintenance of the thermal energy storage system, and management and monitoring systems of the power station.

[0005] At present, the main power consumption equipment of the solar thermal power generation system is electric heating, electric heating, various salt pumps and other high-energy-consuming equipment, which makes the power consumption rate of the power station about 30%;

[0006] When a solar thermal power station is experiencing a power outage, the heating system, anti-condensation system, and control system fail due to power outage, causing the heliostat to focus on the collector for a long time, resulting in damage to the collector equipment. To prevent equipment damage caused by a power outage, a solar thermal power station needs to be equipped with an emergency backup power system (such as a UPS energy storage system) to ensure that key equipment can still obtain the necessary power supply during a power outage, which results in additional investment and reduces the economic benefits of solar thermal power generation. Utility Model Content

[0007] In view of the deficiencies in the above-mentioned prior art, the utility model provides a composite heliostat and solar thermal power generation system based on photovoltaic power generation, which can meet the factory electricity consumption of the solar thermal power generation system by relying on photovoltaic power generation, and does not need to configure a separate emergency backup power supply system, so as to ensure the necessary power supply for key equipment during power outages.

[0008] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0009] A composite heliostat based on photovoltaic power generation, the composite heliostat comprising a mirror body, a photovoltaic panel, a truss and a column;

[0010] A plurality of mirror arrays are arranged and installed at the upper end of the truss to form a heliostat structure; the heliostat structure is used to reflect and concentrate sunlight to a collector; the collector is connected to a generator, and the generator generates electricity using solar thermal energy;

[0011] The photovoltaic panel is installed on the truss at one end of the heliostat structure to generate photovoltaic power; the center of the bottom end of the truss is installed on the top of the column; the photovoltaic panel is connected to the factory power circuit through a cable to supply power to the factory power equipment.

[0012] Furthermore, the area of ​​the photovoltaic panel is 10% to 12% of the area of ​​the heliostat structure.

[0013] Furthermore, the photovoltaic panels are also connected to the public power grid via cables, and surplus electricity is sent to the public power grid.

[0014] Furthermore, the bottom center of the truss is installed on the top of the column through a solar tracking system; the solar tracking system drives the truss to drive the heliostat structure and the photovoltaic panel to synchronously adjust the up and down pitch angles and the horizontal azimuth angles.

[0015] Furthermore, the composite heliostat also includes a photovoltaic power connection box; the photovoltaic power connection box is installed on the column, and a threading hole is provided on the column above the photovoltaic power connection box; the photovoltaic cell panel is connected to the photovoltaic circuit in the photovoltaic power connection box through a cable, and the cable is located on the inner side of the column and passes through the threading hole to enter the photovoltaic power connection box; the photovoltaic circuit outputs electrical energy through the cable lead-out line.

[0016] Furthermore, the mirror body is provided with a coating, and the coating is used to reflect sunlight.

[0017] Furthermore, the coating is vacuum aluminum coating.

[0018] The utility model also discloses a solar thermal power generation system, which includes any of the above-mentioned composite heliostats based on photovoltaic power generation, an inverter, a low-voltage switch cabinet, a high-voltage switch cabinet, a circuit breaker, a plant power bus, and a public power grid bus;

[0019] A plurality of the composite heliostat matrices are arranged to form a heliostat field; the cable lead wires of each row of the composite heliostats are connected to the inverter through cables; the inverter is connected to a low-voltage switch in the low-voltage switch cabinet, and the low-voltage switch is connected to a high-voltage switch cable in the high-voltage switch cabinet through a transformer; the high-voltage switch is connected to each plant power load through a plurality of power distribution switches, and supplies power to the plant power load; the circuit output end of each plant power load is respectively connected to one end of the plant power bus, and the other end of the plant power bus is connected to the public power grid bus cable through the circuit breaker.

[0020] Furthermore, the inverter is connected to the transformer and the heliostat field load through two low-voltage switches through cables.

[0021] Beneficial effects of the utility model:

[0022] The utility model combines the mirror body and the photovoltaic panel through the existing heliostat truss to form a composite heliostat, and uses the photovoltaic power generation of the photovoltaic panel to provide power for factory use, without the need to configure a separate emergency backup power supply system, which greatly reduces the overall investment of the photovoltaic power station and is conducive to the popularization of solar thermal power stations. At the same time, the use of photovoltaic panels to provide factory power improves the stability and reliability of power supply, and also increases the economic benefits of the entire solar thermal power generation system by selling surplus electricity.

[0023] The utility model installs a photovoltaic panel at one end of the heliostat structure according to a certain ratio, thereby ensuring the maximization of the power supply efficiency and economic benefits of the entire photothermal power generation system.

[0024] The utility model realizes the light-chasing characteristic of the heliostat through the sun tracking system, which is beneficial to improving the energy collection efficiency of the solar thermal power generation system, maximizing the capture and utilization of solar energy, and improving the efficiency and output of the entire solar thermal power generation system. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a top view of the composite heliostat based on photovoltaic power generation of the utility model;

[0026] Figure 2 This is a front view of the composite heliostat based on photovoltaic power generation of the utility model;

[0027] Figure 3 The schematic diagram of the photothermal power generation system includes the composite heliostat based on photovoltaic power generation of the utility model.

[0028] Among them: 1-mirror body, 2-photovoltaic panel, 3-truss, 4-wire hole, 5-photovoltaic power connection box, 6-column, 7-cable lead-out line. DETAILED DESCRIPTION

[0029] The following is a further detailed description of the specific implementation of the utility model in conjunction with the accompanying drawings and examples. The following examples are only used to illustrate the utility model, but are not intended to limit the scope of the utility model.

[0030] The terms such as upper, lower, left, right, inside, outside, front end, rear end, head, tail, etc. in this application document are based on the positions or positions shown in the drawings. If the drawings are different, the corresponding positions may also change accordingly, so they cannot be understood as limiting the scope of protection.

[0031] In the present utility model, the terms "install", "connected", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, an integral connection, a mechanical connection, an electrical connection or mutual communication, a direct connection, an indirect connection through an intermediate medium, the internal connection of two components, or the interaction relationship between two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0032] This embodiment describes a composite heliostat and solar thermal power generation system based on photovoltaic power generation, which can provide factory power for the solar thermal power generation system through photovoltaic power generation, avoiding the need to configure a separate emergency backup power supply system.

[0033] like Figure 1 and Figure 2 As shown, the composite heliostat mainly includes a mirror body 1, a photovoltaic panel 2, a truss 3, a photovoltaic power connection box 5 and a column 6.

[0034] Multiple mirror bodies 1 are respectively installed on the upper ends of the trusses 3 in an array arrangement to form a heliostat structure. The heliostat structure plays a focusing role in the entire solar thermal power generation system, reflecting and concentrating sunlight to the collector. The collector can be directly connected to the generator, and the generator uses solar thermal energy to generate electricity, or the collector converts the collected solar thermal energy into steam energy through a heat exchange device, and the generator uses steam energy to generate electricity. In addition, the mirror body 1 is provided with a high-reflectivity coating, which can efficiently reflect sunlight and minimize energy loss. The coating can be vacuum aluminum or other professional reflective coatings.

[0035] At one end of the heliostat structure, a photovoltaic panel 2 is installed on the upper end of the truss 3 to perform photovoltaic power generation, that is, convert sunlight into electrical energy. The electrical energy generated by the photovoltaic panel 2 is transmitted to the factory power circuit through a cable to power the electrical equipment in the solar thermal power generation system. In addition, the photovoltaic panel 2 is also connected to the public power grid, and the surplus electricity exceeding the power required for factory power is sent to the public power grid to generate electricity sales income. At the same time, part of the surplus electricity can be stored in a battery pack, and the battery pack is discharged to supply power for factory power when the power supply is insufficient. Due to the stability of the power output of the photovoltaic panel 2 under the sun, it can replace the emergency backup power supply system of the existing solar thermal power plant. This embodiment reduces equipment investment while increasing income, thereby increasing the economic benefits of the entire solar thermal power generation system.

[0036] The center of the bottom end of the truss 3 is installed on the top of the column 6 through a solar tracking system. While tracking the position of the sun, the solar tracking system drives the truss 3 to drive the heliostat structure and the photovoltaic panel 2 to synchronously adjust the up and down pitch angles and the horizontal azimuth angles, so that the sunlight is vertically irradiated on the heliostat structure and the photovoltaic panel 2, ensuring that the heliostat structure always efficiently focuses the light, and the photovoltaic panel 2 absorbs the sunlight to the maximum extent and converts it into electrical energy, so that the photoelectric conversion efficiency of the photovoltaic panel 2 is maximized. The solar tracking system is connected to the photovoltaic panel 2 through a cable, and the photovoltaic panel 2 provides power for it. The solar tracking system of this embodiment can adopt the solar tracking system adopted by the existing heliostat.

[0037] In this embodiment, the heliostat structure and the photovoltaic panel 2 are integrated into an integrated device through the truss 3 to play a complementary role, and the light-chasing characteristics of the heliostat are realized through the solar tracking system, which is beneficial to improving the energy collection efficiency of the solar thermal power generation system, maximizing the capture and utilization of solar energy, and improving the efficiency and output of the entire solar thermal power generation system.

[0038] In this embodiment, the photovoltaic power connection box 5 is installed on the lower side of the column 6, and a threading hole 4 is provided on the column 6 above the photovoltaic power connection box 5. The cable for outputting electric energy from the photovoltaic panel 2 extends from the column 6 to the top of the photovoltaic power connection box 5, passes through the column 6 through the threading hole 4, and is connected to the photovoltaic circuit in the photovoltaic power connection box 5. The cable lead-out line 7 extends from the bottom of the photovoltaic power connection box 5 to be connected to the solar thermal power generation system circuit.

[0039] In this embodiment, the photovoltaic power connection box 5 also includes a heliostat control module and a power distribution network module. The heliostat control module is connected to the solar tracking system and is used to control the solar tracking system to adjust the angle and direction of the heliostat in real time. The power distribution network module is wirelessly connected to the central control center through the network, and the power distribution network module is connected to the heliostat control module and the photovoltaic circuit respectively. The operator can transmit control instructions to the photovoltaic power connection box 5 through the power distribution network module.

[0040] The composite heliostat of this embodiment adopts a combination of photovoltaic panels 2 + mirror body 1. Preferably, the photovoltaic panels 2 are set to a size of 10% to 12% of the heliostat structure area. Taking a 100MW heliostat field as an example, the heliostat field includes 27,760 heliostats, each of which has an area of ​​30 square meters. The power supply in the solar thermal power generation system currently mainly includes high-power plant equipment such as molten salt, electric heating, and salt pumps. The plant power capacity is about 26MW, that is, the plant power rate is about 26%. If the current mainstream 665Wp photovoltaic module in China is used, its specification size is calculated as 1.60m×0.99m, and the optimal photovoltaic use area of ​​each heliostat is 2.23㎡. Taking into account the shape matching coefficient of the photovoltaic panel 2, each heliostat uses two photovoltaic panels 2, and the photovoltaic area is 3.17㎡, that is, the area of ​​the photovoltaic panel 2 in each heliostat is 10.6% of the heliostat structure area. At this time, the power supply efficiency and economic benefits of the entire solar thermal power generation system are maximized.

[0041] The composite heliostat of this embodiment is used in a solar thermal power generation system. A plurality of composite heliostats are arranged in a matrix to form a heliostat field. The electric energy generated by the photovoltaic panels 2 in the heliostat field is connected to the circuit of the solar thermal power generation system through cables to supply power to the plant power load.

[0042] like Figure 3 As shown, the cable lead-out lines 7 for outputting the electric energy of the photovoltaic panels 2 of each row of composite heliostats are connected in series through cables, and the heliostat field is divided into multiple groups of heliostats, each group of heliostats is connected to the inverter through cables, and multiple inverters are connected in series through cables. Multiple inverters can be installed in low-voltage switch cabinets, and the inverters are connected to two low-voltage switches in the low-voltage switch cabinet through cables, one low-voltage switch is connected to the high-voltage switch cable in the high-voltage switch cabinet through a transformer, and the other low-voltage switch is transmitted to the heliostat field load (such as a solar tracking system) through cables to supply power to the heliostat field load. The high-voltage switch is connected to each plant power load through multiple power distribution switches, and supplies power to the plant power load. The circuit output end of each power supply load is connected to one end of the power supply busbar, and the other end of the power supply busbar is connected to the public power grid busbar through a cable. In this section of cable, circuit breakers are installed near the ends of the power supply busbar and the public power grid busbar. The circuit breakers can control the on and off of the circuits connected to the public power grid, and automatically cut off the current when abnormal conditions such as overload or short circuit occur in the circuit to avoid damage to the circuit and electrical equipment. In this embodiment, the power supply busbar can use a 10KV busbar, and the public power grid busbar can use a 110KV busbar.

[0043] Although the principle of the present invention is described in detail above in conjunction with the preferred embodiments of the present invention, those skilled in the art should understand that the above embodiments are merely explanations of the exemplary implementation of the present invention, and are not intended to limit the scope of the present invention. The details in the embodiments do not constitute limitations on the scope of the present invention. Without departing from the spirit and scope of the present invention, any obvious changes such as equivalent transformations and simple replacements based on the technical solution of the present invention fall within the scope of protection of the present invention.

Claims

1. A composite heliostat based on photovoltaic power generation, characterized in that: The composite heliostat comprises a mirror body (1), a photovoltaic panel (2), a truss (3) and a column (6); A plurality of mirror bodies (1) are arranged in an array and installed on the upper end of the truss (3) to form a heliostat structure; the heliostat structure is used to reflect and concentrate sunlight onto a collector; the collector is connected to a generator, and the generator generates electricity using solar thermal energy; At one end of the heliostat structure, the photovoltaic panel (2) is mounted on the truss (3) to perform photovoltaic power generation; the center of the bottom end of the truss (3) is mounted on the top of the column (6); the photovoltaic panel (2) is connected to the factory power circuit via a cable to supply power to the factory power equipment.

2. The composite heliostat based on photovoltaic power generation according to claim 1, characterized in that: The area of ​​the photovoltaic cell panel (2) is 10% to 12% of the area of ​​the heliostat structure.

3. The composite heliostat based on photovoltaic power generation according to claim 1, characterized in that: The photovoltaic panel (2) is also connected to a public power grid via a cable, and surplus electricity is fed into the public power grid.

4. The composite heliostat based on photovoltaic power generation according to claim 1, characterized in that: The center of the bottom end of the truss (3) is installed on the top of the column (6) through a solar tracking system; the solar tracking system drives the truss (3) to drive the heliostat structure and the photovoltaic panel (2) to synchronously adjust the vertical pitch angle and the horizontal azimuth angle.

5. The composite heliostat based on photovoltaic power generation according to claim 1, characterized in that: The composite heliostat further comprises a photovoltaic power connection box (5); the photovoltaic power connection box (5) is mounted on the column (6), and a threading hole (4) is provided on the column (6) above the photovoltaic power connection box (5); the photovoltaic battery panel (2) is connected to a photovoltaic circuit in the photovoltaic power connection box (5) via a cable, and the cable is located on the inner side of the column (6) and passes through the threading hole (4) into the photovoltaic power connection box (5); the photovoltaic circuit outputs electric energy via a cable lead-out line (7).

6. The composite heliostat based on photovoltaic power generation according to claim 1, characterized in that: The mirror body (1) is provided with a coating, and the coating is used to reflect sunlight.

7. The composite heliostat based on photovoltaic power generation according to claim 6, characterized in that: The coating is vacuum aluminum coating.

8. A solar thermal power generation system, characterized in that: The solar thermal power generation system comprises the composite heliostat based on photovoltaic power generation as described in any one of claims 1 to 7, an inverter, a low-voltage switch cabinet, a high-voltage switch cabinet, a circuit breaker, a plant power bus, and a public power grid bus; A plurality of said composite heliostats are arranged in a matrix to form a heliostat field; the cable lead wires (7) of each row of said composite heliostats are connected to said inverter through cables; said inverter is connected to a low-voltage switch in said low-voltage switch cabinet, and said low-voltage switch is connected to a high-voltage switch cable in said high-voltage switch cabinet through a transformer; said high-voltage switch is connected to each plant power load through a plurality of power distribution switches, and supplies power to said plant power load; the circuit output end of each plant power load is connected to one end of said plant power bus, and the other end of said plant power bus is connected to said public power grid bus cable through said circuit breaker.

9. The solar thermal power generation system according to claim 8, characterized in that: The inverter is connected to the transformer and the heliostat field load through two low-voltage switches through cables.

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