Photovoltaic system

Abstract

The invention discloses a photovoltaic system. The system comprises a photovoltaic module, an arc-shaped reflecting plate and a supporting structure, the arc-shaped reflecting plate is arranged below the photovoltaic module, and the projection of the arc-shaped reflecting plate coincides with the projection of the photovoltaic module in the vertical direction; an opening of the arc-shaped reflecting plate is downward, and the arc-shaped reflecting plate is used for diffusing and reflecting incident light on the arc-shaped reflecting plate to the back surface of the photovoltaic module; the height from the top of the arc-shaped reflecting plate to the ground and the curvature radius are determined based on the projection width of the arc-shaped reflecting plate in the vertical direction and the height from the center of the photovoltaic module to the ground; and the supporting structure is used for supporting the photovoltaic module and the arc-shaped reflecting plate. According to the photovoltaic system, the arc-shaped reflecting plate with the downward opening is arranged below the photovoltaic module, so that the influence of vegetation below the photovoltaic module on the photovoltaic module can be eliminated while the back gain of the photovoltaic module is increased.

Description

Technical Field

[0001] Embodiments of the present invention relate to the technical field of photovoltaic power generation, and particularly to a photovoltaic system. Background Art

[0002] In some mountain projects or ground projects, double-sided double-glass photovoltaic modules can be used. Under certain installation inclination angles, heights from the ground, and ground reflectivities, the reflected light and scattered light in the environment are utilized to obtain the backside gain of the photovoltaic modules, so as to increase the power generation of the system and reduce the power generation cost.

[0003] The ground reflectivity is the core factor affecting the backside gain of the photovoltaic modules. For example, the backside gain of the photovoltaic modules is relatively high under high-reflectivity backgrounds such as snow fields and white-painted grounds, while the backside gain of the photovoltaic modules is relatively limited under low-reflectivity backgrounds such as vegetation or dark ground surfaces. In a mountain environment with a complex surface type (such as a mixture of rocks, soil, and vegetation), the reflection conditions need to be optimized according to specific areas. The above problems result in the inability to fully obtain the backside gain of the photovoltaic modules under different backgrounds.

[0004] In addition, the growth of weeds under the photovoltaic modules may also bring some problems. For example, dry weeds are an important factor in fire hazards, especially in winter and spring. Moreover, the growth of weeds may also impact and damage the photovoltaic modules, or block the photovoltaic modules, affecting the backside gain of the photovoltaic modules. Summary of the Invention

[0005] The present invention provides a photovoltaic system, which can increase the backside gain of the photovoltaic modules while eliminating the influence of vegetation under the photovoltaic modules on the photovoltaic modules.

[0006] In a first aspect, embodiments of the present invention provide a photovoltaic system, including: a photovoltaic module, a circular arc-shaped reflector, and a support structure;

[0007] The circular arc-shaped reflector is arranged below the photovoltaic module, and the circular arc-shaped reflector coincides with the projection of the photovoltaic module in the vertical direction;

[0008] The circular arc-shaped reflector has an opening facing downwards, and is used for diffusely reflecting the incident light on the circular arc-shaped reflector to the back of the photovoltaic module;

[0009] The height of the top of the circular arc-shaped reflector from the ground and the radius of curvature are determined based on the projection width of the circular arc-shaped reflector in the vertical direction and the height of the center of the photovoltaic module from the ground;

[0010] The support structure is used to support the photovoltaic module and the circular arc-shaped reflector.

[0011] Further, the following conditions are satisfied among the height of the top from the ground, the radius of curvature, the projection width, and the height of the center from the ground:

[0012] R ≥ W 2 / (8ΔH) + ΔH / 2; ΔH = H 总 -H;

[0013] Wherein, R is the radius of curvature; W is the projection width; H 总 is the height of the center from the ground; H is the height of the top from the ground.

[0014] Further, the support structure includes: a first column and a second column, a diagonal beam and connectors, a cross beam and connectors, and a fixing hoop;

[0015] Wherein, the first column and the second column, the diagonal beam and connectors, and the cross beam and connectors jointly support the photovoltaic module at a set inclination angle with the ground; the fixing hoop fixes the arc-shaped reflector on the first column and the second column and ensures that the top of the arc-shaped reflector is parallel to the ground; the first column and the second column are arranged longitudinally.

[0016] Further, the first column and the second column are set according to the weight of the photovoltaic module, the weight of the arc-shaped reflector, and the wind load condition.

[0017] Further, the photovoltaic module is fixed on the cross beam; one side of the cross beam is connected to the diagonal beam, and the other side of the diagonal beam is connected to the first column and the second column, and the diagonal beam forms a set inclination angle with the ground.

[0018] Further, the photovoltaic module is fixed on the cross beam by bolts or clamps.

[0019] Further, the first column and the second column form a column pair and are connected to the diagonal beam, and the number of the column pairs is multiple.

[0020] Further, the diagonal beam forms a triangular structure with the first column and the second column in each column pair respectively through the bracket strut in the connectors of the diagonal beam.

[0021] Further, the arc-shaped reflector is formed by forging white galvanized steel plates or lightweight aluminum alloys.

[0022] Further, the reflectivity of the arc-shaped reflector is determined by establishing a surface equation of the arc-shaped reflector, calculating the reflectivity of each point in the surface equation, and performing a surface integral based on the reflectivity of each point.

[0023] The present invention provides a photovoltaic system, comprising: a photovoltaic module, an arc-shaped reflector, and a support structure; the arc-shaped reflector is disposed below the photovoltaic module, and the arc-shaped reflector coincides with the projection of the photovoltaic module in the vertical direction; the arc-shaped reflector has an opening facing downward and is configured to diffusely reflect the incident light on the arc-shaped reflector to the back surface of the photovoltaic module; the height of the top of the arc-shaped reflector from the ground and the radius of curvature are determined based on the width of the projection of the arc-shaped reflector in the vertical direction and the height of the center of the photovoltaic module from the ground; the support structure is used to support the photovoltaic module and the arc-shaped reflector. In this photovoltaic system, an arc-shaped reflector with an opening facing downward is disposed below the photovoltaic module. Under different working environments, the arc-shaped reflector can diffusely reflect light to the back surface of the photovoltaic module, and at the same time, the arc-shaped reflector can block the growth of the vegetation below, that is, it can increase the gain on the back surface of the photovoltaic module while eliminating the influence of the vegetation below the photovoltaic module on the photovoltaic module.

[0024] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present invention, nor is it used to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0026] Figure 1 FIG. 1 is a schematic structural diagram of a photovoltaic system according to Embodiment 1 of the present invention;

[0027] Figure 2 FIG. 2 is a front view of a photovoltaic system according to Embodiment 1 of the present invention;

[0028] Figure 3 FIG. 3 is a left side view of a photovoltaic system according to Embodiment 1 of the present invention;

[0029] Figure 4 FIG. 4 is a left side view of another photovoltaic system according to Embodiment 1 of the present invention;

[0030] Figure 5 FIG. 5 is a schematic structural diagram of a photovoltaic system according to Embodiment 2 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] In order to enable those skilled in the art to better understand the solution of the present invention, the following will clearly and completely describe the technical solution in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0032] It should be noted that the terms "first", "second", etc. in the present invention are used to distinguish similar objects, and do not necessarily need to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances, so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0033] Embodiment 1

[0034] Figure 1 is a schematic structural diagram of a photovoltaic system provided according to Embodiment 1 of the present invention. This embodiment is applicable to the situation of setting a photovoltaic system to increase the gain on the back of the photovoltaic module while eliminating the influence of the vegetation below the photovoltaic module on the photovoltaic module.

[0035] As Figure 1 shown, the present invention provides a photovoltaic system, comprising:

[0036] a photovoltaic module 10, a circular arc reflector 20, and a support structure 30;

[0037] The circular arc reflector 20 is disposed below the photovoltaic module 10, and the projection of the circular arc reflector 20 in the vertical direction coincides with that of the photovoltaic module 10;

[0038] The circular arc reflector 20 has an opening facing downwards, and is used to diffusely reflect the incident light on the circular arc reflector 20 to the back of the photovoltaic module 10;

[0039] The height of the top of the circular arc reflector 20 from the ground and the radius of curvature are determined based on the projection width of the circular arc reflector 20 in the vertical direction and the height of the center of the photovoltaic module 10 from the ground;

[0040] The support structure 30 is used to support the photovoltaic module 10 and the circular arc reflector 20.

[0041] Among them, the photovoltaic module 10 can be divided into a back side and a front side. The front side can be the side that directly absorbs sunlight and converts it into electrical energy, and the back side can be the side facing the ground, and the back side also has the ability to absorb light and generate electrical energy. In an environment with reflected light, compared with a single-sided photovoltaic module, a double-sided photovoltaic module can absorb more light energy and can significantly increase the power generation.

[0042] Regarding the design of the arc-shaped reflector 20 in the embodiments of the present invention, the specific description is as follows:

[0043] To improve the back-side gain of the photovoltaic module, it is considered to place an arc-shaped reflector below the photovoltaic module. The light incident on the arc-shaped reflector is reflected to the back side of the photovoltaic module by the arc-shaped reflector. The light incident on the arc-shaped reflector can be direct sunlight and diffuse reflected light from the surrounding environment. Among them, the back-side gain of the photovoltaic module can be understood as the additional light received by the back side of the photovoltaic module and the additional electrical energy output generated therefrom. The arc-shaped reflector can be understood as a reflector with an overall arc shape, that is, a reflector with a certain curvature.

[0044] The curvature of the arc-shaped reflector needs to ensure that the incident light can cover the back area of the photovoltaic module maximally after reflection. Ideally, a parabolic reflector has the best reflection effect. Among them, the principle of the parabolic reflector reflecting light can be: the geometric characteristics of the parabola can diffusely reflect parallel incident light to the back side of the photovoltaic module. If the back side of the photovoltaic module is arranged in the reflected light area of the parabolic reflector, the utilization rate of the reflected light can be maximized.

[0045] On this basis, the embodiments of the present invention adopt the arc-shaped reflector 20 to improve the back-side gain of the photovoltaic module. The arc-shaped reflector 20 can be a special form of the arc-shaped reflector, and its shape can be an arc surface including a part of a circle. Due to the high symmetry and regularity of the arc shape, this regular shape makes the light reflection more regular. Its radius of curvature is fixed, and the bending degree of the entire arc surface is relatively uniform, which provides convenience for precisely controlling the light reflection.

[0046] In the embodiments of the present invention, the arc-shaped reflector 20 can be arranged below the photovoltaic module 10, that is, the arc-shaped reflector 20 can be arranged in the area between the back side of the photovoltaic module 10 and the ground; the vertical projection of the arc-shaped reflector 20 coincides with that of the photovoltaic module 10. It can be understood that in practical applications, the projection of the arc-shaped reflector 20 on the ground coincides with that of the photovoltaic module 10, and the lengths and widths of their projections on the ground are the same; the arc-shaped reflector 20 opens downward, that is, the convex surface of the arc-shaped reflector 20 faces the back side of the photovoltaic module 10, and the incident light of the arc-shaped reflector 20 can be diffusely reflected to the back side of the photovoltaic module 10 through the convex surface reflection.

[0047] Figure 2 It is a front view of a photovoltaic system provided according to Embodiment 1 of the present invention. Figure 3 It is a left side view of a photovoltaic system provided according to Embodiment 1 of the present invention. Combining Figure 1 、 Figure 2 、 Figure 3 it can be known that the arc-shaped reflector 20 is arranged below the photovoltaic module 10, and the arc-shaped reflector 20 has the same projected length and projected width as the photovoltaic module 10 on the ground, and the arc-shaped reflector 20 opens downward.

[0048] The principle of the arc-shaped reflector 20 reflecting light can be: the incident angle matches the reflection angle, and the normal direction of the arc is the radius direction from the center of the circle to the reflection point; the reflected light needs to cover the back of the photovoltaic module 10 as much as possible, which can be achieved by adjusting the center position, central angle, radius of curvature, etc. A larger central angle can expand the reflection range, but light scattering needs to be avoided.

[0049] For the setting of the arc-shaped reflector 20, it is necessary to make the light reflected by the arc-shaped reflector 20 cover all areas of the back of the photovoltaic module 10 as much as possible to avoid shadows; it is necessary to make the light reflected by the arc-shaped reflector 20 concentrate on the back of the photovoltaic module 10 to reduce energy loss. Based on the foregoing requirements, it is necessary to reasonably set the radius of curvature and the height of the top from the ground of the arc-shaped reflector 20.

[0050] In the embodiment of the present invention, the height of the top of the arc-shaped reflector 20 from the ground and the radius of curvature can be determined based on the projected width of the arc-shaped reflector 20 in the vertical direction and the height of the center of the photovoltaic module 10 from the ground. Among them, the radius of curvature of the arc-shaped reflector 20 can be the radius of the imaginary circle corresponding to the arc-shaped reflector 20. The radius of curvature determines the degree of bending of the arc-shaped reflector 20. The larger the radius of curvature, the smaller the degree of bending; the smaller the radius of curvature, the greater the degree of bending. The height of the top of the arc-shaped reflector 20 from the ground can be understood as the vertical distance from the highest point of the arc surface of the arc-shaped reflector 20 to the ground. The projected width of the arc-shaped reflector 20 in the vertical direction can be understood as the projected width of the vertical projection of the arc-shaped reflector 20 on the ground, and the projected width is the width in the longitudinal direction. The height of the center of the photovoltaic module 10 from the ground can be understood as the vertical distance from the center point of the photovoltaic module 10 to the ground.

[0051] For determining the height of the top of the arc-shaped reflector 20 from the ground, the height of the center of the photovoltaic module 10 from the ground can be used as a reference. If the height of the center from the ground is relatively high, in order to enable the light reflected by the arc-shaped reflector 20 to effectively irradiate the back of the photovoltaic module 10, the height of the top from the ground should also be increased accordingly, ensuring that the height of the top from the ground is less than the height of the center from the ground. The projected width of the arc-shaped reflector 20 in the vertical direction will also affect the setting of the height of the top from the ground. If the projected width is relatively large, the height of the top from the ground should also be increased accordingly to ensure that the reflected light can reach the back of the photovoltaic module 10 smoothly.

[0052] For determining the radius of curvature of the arc-shaped reflector 20, the height of the center of the photovoltaic module 10 from the ground should also be referred to. If the height of the center from the ground is relatively high, the radius of curvature may need to be relatively large, so that the light can have a more appropriate propagation path to reach the corresponding position after reflection. The projected width of the arc-shaped reflector 20 in the vertical direction will also affect the setting of the radius of curvature. For example, a wider projected width may mean that a more gentle arc (larger radius of curvature) is needed to evenly reflect the light onto the photovoltaic module; while a narrower projected width may allow the use of an arc with a smaller radius of curvature (more curved) to concentrate the light on a specific part of the photovoltaic module 10.

[0053] Figure 4 is a left side view of another photovoltaic system provided according to Embodiment 1 of the present invention. Figure 4 is in Figure 3 Based on the shown left side view, markings for the above-mentioned projected width W, height H of the center from the ground 总 , and height H of the top from the ground are added. Optionally, the following conditions are satisfied among the height of the top from the ground, the radius of curvature, the projected width, and the height of the center from the ground: R≥W 2 / (8ΔH)+ΔH / 2; ΔH = H 总 -H; where R is the radius of curvature; W is the projected width; H 总 is the height of the center from the ground; and H is the height of the top from the ground. By satisfying the above conditions, the incident light of the arc-shaped reflector 20 can maximize the coverage of the back area of the photovoltaic module 10 after diffuse reflection.

[0054] Optionally, in practical applications, the distance from the top of the arc-shaped reflector 20 to the back of the photovoltaic module 10 can be 600 - 1000 mm.

[0055] Optionally, the arc-shaped reflector 20 is formed by forging a white galvanized steel plate or a lightweight aluminum alloy. By forging the arc-shaped reflector 20 from a white galvanized steel plate or a lightweight aluminum alloy, the arc-shaped reflector 20 can have a high reflectivity, which is beneficial to improving the gain on the back of the photovoltaic module.

[0056] In the embodiment of the present invention, the support structure 30 is used to support the photovoltaic module 10 and the arc-shaped reflector 20. Specifically, the support structure 30 can be used to support the photovoltaic module 10 to be laid at the above-mentioned central height from the ground and at a certain inclination angle (not limited); it can be used to support the arc-shaped reflector 20 with the opening facing downwards to be arranged on the back of the photovoltaic module 10 with the above-mentioned radius of curvature and the above-mentioned top height from the ground. The top of the arc-shaped reflector 20 is parallel to the ground, and the arc-shaped reflector 20 and the photovoltaic module 10 overlap in the vertical projection. The support structure 30 can be Figure 1 all the structures in the photovoltaic system shown except the photovoltaic module 10 and the arc-shaped reflector 20.

[0057] Optionally, one or more of the inclination angle of the photovoltaic module 10, the central height from the ground, the radius of curvature of the arc-shaped reflector 20, and the top height from the ground can be optimized through a ray tracing model to ensure that the annual light incident angle adapts to the mountain terrain.

[0058] The present invention provides a photovoltaic system, including: a photovoltaic module, an arc-shaped reflector, and a support structure; the arc-shaped reflector is arranged below the photovoltaic module, and the arc-shaped reflector and the photovoltaic module overlap in the vertical projection; the arc-shaped reflector has an opening facing downwards and is used to diffusely reflect the incident light on the arc-shaped reflector to the back of the photovoltaic module; the top height from the ground and the radius of curvature of the arc-shaped reflector are determined based on the projected width of the arc-shaped reflector in the vertical direction and the central height from the ground of the photovoltaic module; the support structure is used to support the photovoltaic module and the arc-shaped reflector. In this photovoltaic system, an arc-shaped reflector with an opening facing downwards is arranged below the photovoltaic module. Under different working environments, the arc-shaped reflector can diffusely reflect light to the back of the photovoltaic module, and at the same time, the arc-shaped reflector can block the growth of the vegetation below, that is, it can increase the gain on the back of the photovoltaic module while eliminating the influence of the vegetation below the photovoltaic module on the photovoltaic module.

[0059] Embodiment 2

[0060] Figure 5 is a schematic structural diagram of a photovoltaic system according to Embodiment 2 of the present invention. The embodiment of the present invention can be a further refinement of the support structure based on the above-mentioned Embodiment 1.

[0061] In an embodiment of the present invention, the support structure 30 includes: a first upright column 31, a second upright column 32, a diagonal beam and a connector 33, a cross beam and a connector 34, and a fixed hoop 35; wherein, the first upright column 31, the second upright column 32, the diagonal beam and the connector 33, and the cross beam and the connector 34 jointly support the photovoltaic module 10 at a set inclination angle with respect to the ground; the fixed hoop 35 fixes the arc-shaped reflector 20 on the first upright column 31 and the second upright column 32 and ensures that the top of the arc-shaped reflector 20 is parallel to the ground; the first upright column 31 and the second upright column 32 are arranged longitudinally.

[0062] Among them, the first upright column 31 and the second upright column 32 can be two upright columns with different heights. Generally, the relatively lower-height upright column can be used as the first upright column 31, and the relatively higher-height upright column can be used as the second upright column 32. The first upright column 31 and the second upright column 32 are arranged longitudinally, that is, the first upright column 31 and the second upright column 32 are arranged in the longitudinal direction. The first upright column 31 and the second upright column 32 can form a pair of upright columns, and the number of pairs of upright columns can be multiple. The photovoltaic module 10 and the arc-shaped reflector 20 are jointly supported by multiple pairs of upright columns.

[0063] The first upright column 31, the second upright column 32, the diagonal beam and the connector 33, and the cross beam and the connector 34 jointly support the photovoltaic module 10 at a set inclination angle with respect to the ground. As Figure 5 can be seen, specifically, the cross beam and the connector 34 can directly support the photovoltaic module 10, and the diagonal beam and the connector 33 are simultaneously connected to the cross beam and the connector 34, the first upright column 31 and the second upright column 32, so that the photovoltaic module 10 forms a set inclination angle with respect to the ground. The set inclination angle is not limited and can be selected according to actual application needs, and can be continuously optimized according to actual situations after selection. The connectors corresponding to the cross beam or the diagonal beam are not limited, as long as they can achieve corresponding support, connection and other functions. Exemplarily, the connector of the diagonal beam includes a bracket brace and a structure for fixing the bracket brace.

[0064] As Figure 5 shown, there can be multiple fixed hoops 35. Fixed hoops 35 can be provided at the intersections of the arc-shaped reflector 20 with the first upright column 31 and the second upright column 32. The arc-shaped reflector 20 can be fixed on the first upright column 31 and the second upright column 32 by multiple fixed hoops 35, and it is ensured that the top of the arc-shaped reflector 20 is parallel to the ground.

[0065] In one embodiment, the first upright column 31 and the second upright column 32 are set according to the weight of the photovoltaic module 10, the weight of the arc-shaped reflector 20, and the wind load conditions.

[0066] Among them, the photovoltaic module 10 and the arc-shaped reflector 20 are important components of the photovoltaic system, and their weights will exert pressure on the support structure. If the photovoltaic module 10 and the arc-shaped reflector 20 are heavy, in order to safely and stably support these weights, the first upright column 31 and the second upright column 32 need to have sufficient strength and load-bearing capacity. For example, heavier photovoltaic module 10 and arc-shaped reflector 20 may require the first upright column 31 and the second upright column 32 to be made of stronger materials or increase the number of upright columns.

[0067] Wind load is a dynamic load acting on the photovoltaic system. Wind speed, direction, and duration vary in different regions and under different meteorological conditions. When the wind blows towards the photovoltaic module 10 and the arc-shaped reflector 20, it will generate pressure and suction, exerting lateral forces on the upright columns. Therefore, when setting the first upright column 31 and the second upright column 32, the local wind load conditions must be fully considered.

[0068] In one embodiment, the photovoltaic module 10 is fixed on the cross beam 34; the cross beam 34 is connected to one side of the inclined beam 33, and the other side of the inclined beam 33 is connected to the first upright column 31 and the second upright column 32, and the inclined beam 33 forms a set inclination angle with the ground. As Figure 5 shown, the photovoltaic module 10 is fixed on a plurality of cross beams 34, and the plurality of cross beams 34 are all fixed on one side of the inclined beam 33. The other side of the inclined beam 33 (the side facing the ground) is connected to a plurality of first upright columns 31 and second upright columns 32, and the inclined beam 33 forms a set inclination angle with the ground.

[0069] In one embodiment, the photovoltaic module 10 is fixed on the cross beam 34 by bolts or clamps. Fixing the photovoltaic module 10 on the cross beam 34 by bolts or clamps ensures that the components are arranged neatly and at consistent intervals, enabling the cross beam 34 to bear the weight of the photovoltaic module 10 and external loads (such as wind pressure, snow accumulation, etc.), and transfer the loads to the upright columns and the foundation.

[0070] In one embodiment, the first upright column 31 and the second upright column 32 form a pair of upright columns connected to the inclined beam 33, and the number of the pair of upright columns is multiple. The arrangement spacing of the pair of upright columns connected to the inclined beam 33 can be set according to actual application requirements.

[0071] In one embodiment, the inclined beam 33 forms a triangular structure with the first upright column 31 and the second upright column 32 in each pair of upright columns respectively through the bracket brace in the connecting member of the inclined beam. As Figure 5As shown, the inclined beam, the support brace, and the first upright column 31 form a triangular structure, and the inclined beam, the support brace, and the second upright column 32 form a triangular structure. The advantage of such a setting is that the inclined beam connects the upright column and the crossbeam through an inclined angle to form a stable triangular structure (truss structure), significantly improving the overall rigidity of the support and its wind and snow load resistance capabilities, reducing the risk of deformation under external forces, and transferring the photovoltaic module 10 and external loads (such as wind pressure and snow accumulation) to the upright column and the foundation, avoiding structural damage caused by local stress concentration.

[0072] In one embodiment, the reflectivity of the circular arc-shaped reflector is determined by establishing the surface equation of the circular arc-shaped reflector, calculating the reflectivity of each point in the surface equation, and performing surface integral based on the reflectivity of each point.

[0073] When calculating the reflectivity of the circular arc-shaped reflector in the embodiment of the present invention, it is necessary to first establish the surface equation of the circular arc-shaped reflector and calculate the normal vector n of each point in the surface equation i ; calculate the local incident angle θ corresponding to each point in the surface equation i , θ i = arccos(n i ·1), where 1 represents the incident direction of sunlight (unit vector), that is, the local incident angle satisfies cosθ i = n i ·1; substitute the local incident angle θ i into the Fresnel equation to calculate the local reflectivity ρ(θ i ) corresponding to θ i ; perform surface integral based on the local reflectivity ρ(θ i ) to obtain the overall reflectivity, that is, the reflectivity ρ of the circular arc-shaped reflector total = 1 / A∫ S ρ(θ i )dA, where S can be understood as the surface of the circular arc-shaped reflector, and A can be understood as the area microelement of the surface S.

[0074] Optionally, in practical applications, the reflectivity of the circular arc-shaped reflector can be determined by the following simplified formula: where ρ(θ i ) = ρ0·(1 - 0.1·sin 2 θ i ), ρ0 is the normal reflectivity, that is, the reflectivity when θ i is 0.

[0075] Through the determination of the reflectivity of the above circular arc-shaped reflector, the gain on the back surface of the photovoltaic module can be further determined.

[0076] A photovoltaic system provided by an embodiment of the present invention greatly improves the gain on the back side of a photovoltaic module compared with a photovoltaic system without an arcuate reflector with a downward opening arranged below the photovoltaic module. Taking the photovoltaic system of the embodiment of the present invention as an experimental group and the photovoltaic system of the embodiment of the present invention without the arcuate reflector as a control group, compared with the control group, the overall system efficiency of the experimental group is increased from 85.4% to 91.27%, the power generation amount is increased from 3,557,821 kWh / year to 3,801,599 kWh / year, the power generation amount per unit system is increased from 1,680 kWh / kWp / year to 1,795 kWh / kWp / year, and the gain on the back side of the photovoltaic module is increased from 7.98% to 17.08%. It can be seen that the photovoltaic system of the embodiment of the present invention plays a significant role in improving the ground photovoltaic benefit.

[0077] Note that the above is only a preferred embodiment of the present invention and the applied technical principle. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein. Various obvious changes, re-adjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A photovoltaic system, characterized in that: include: Photovoltaic panels, arc-shaped reflectors and supporting structures; The arc-shaped reflector is arranged below the photovoltaic assembly, and the projection of the arc-shaped reflector and the photovoltaic assembly in the vertical direction coincides; The arc-shaped reflector has an opening downward, and is used to diffuse and reflect incident light on the arc-shaped reflector to the back of the photovoltaic module; The height of the top of the arc-shaped reflector from the ground and the radius of curvature are determined based on the projection width of the arc-shaped reflector in the vertical direction and the height of the center of the photovoltaic module from the ground; The supporting structure is used to support the photovoltaic assembly and the arc-shaped reflector.

2. The system according to claim 1, characterized in that The height of the top from the ground, the radius of curvature, the projection width and the height of the center from the ground meet the following conditions: R≥W 2 / (8ΔH)+ΔH / 2;ΔH=H 总 -H; Wherein, R is the radius of curvature; W is the projection width; H 总 is the height of the center from the ground; H is the height of the top from the ground.

3. The system according to claim 1, characterized in that The support structure comprises: a first column and a second column, an inclined beam and a connecting piece, a cross beam and a connecting piece, and a fixed hoop; Among them, the first column and the second column, the inclined beam and the connecting parts, and the cross beam and the connecting parts jointly support the photovoltaic module to form a set inclination angle with the ground; the fixed hoop fixes the arc-shaped reflector on the first column and the second column and ensures that the top of the arc-shaped reflector is parallel to the ground; the first column and the second column are arranged longitudinally.

4. The system according to claim 3, characterized in that The first column and the second column are set according to the weight of the photovoltaic module, the weight of the arc-shaped reflector and the wind load.

5. The system according to claim 3, characterized in that The photovoltaic assembly is fixed on the crossbeam; the crossbeam is connected to one side of the inclined beam, the other side of the inclined beam is connected to the first column and the second column, and the inclined beam forms a set inclination angle with the ground.

6. The system according to claim 5, characterized in that The photovoltaic components are fixed on the crossbeams by bolts or clamps.

7. The system according to claim 5, characterized in that The first column and the second column form a column pair connected to the inclined beam, and the number of the column pairs is multiple.

8. The system according to claim 7, characterized in that The inclined beam is braced diagonally by the brackets in the connecting member of the inclined beam, and forms a triangular structure with the first column and the second column in each column pair.

9. The system according to claim 1, characterized in that The arc-shaped reflective plate is formed by forging a white galvanized steel plate or a light aluminum alloy.

10. The system according to claim 1, characterized in that The reflectivity of the arc-shaped reflective plate is determined by establishing a surface equation of the arc-shaped reflective plate, calculating the reflectivity of each point in the surface equation, and performing surface integral based on the reflectivity of each point.

Images