Photovoltaic system and adjusting method

Abstract

The invention discloses a photovoltaic system and an adjusting method, and belongs to the technical field of photovoltaic power generation, the photovoltaic system comprises multiple rows of photovoltaic power generation units, the multiple rows of photovoltaic power generation units respectively form a first array group and a second array group, and the first array group and the second array group are arranged in a staggered manner; the breadth width of each row of photovoltaic power generation units in the first array group is greater than that of each row of photovoltaic power generation units in the second array group; a gap is arranged between the first array subgroup and the second array subgroup, the first array subgroup and the second array subgroup are set to be in different postures, or the postures of the first array subgroup and / or the second array subgroup are adjusted, and differentiated adjusting strategies are executed. Sunlight can be better received, the field utilization efficiency is improved, the adjustment flexibility is improved, and the power generation performance of a photovoltaic system can be improved.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic power generation technology, specifically to a photovoltaic system and regulation method. Background Technology

[0002] As the core component for converting solar energy into electrical energy, the structure and installation arrangement of photovoltaic modules are of great importance.

[0003] In the prior art, the adjustment methods of tracking photovoltaic systems include apparent solar tracking adjustment and reverse tracking adjustment. Their common feature is to adjust all independently adjustable photovoltaic units to the same or similar posture, that is, "homogenization adjustment", so that sunlight shines evenly on each photovoltaic unit and minimizes mutual shading.

[0004] At the same time, the density of the arrangement of tracking photovoltaic systems is usually lower than that of fixed-mount photovoltaic systems, that is, the ground coverage (GCR) is relatively low. Therefore, at certain times, more "gap light" will be generated that is projected into the gaps between the rows of photovoltaic power generation units. As a result, additional technical means are needed to enhance the utilization of gap light, which increases the complexity of the system and the external interference factors of the system.

[0005] Ground Coverage Rate (GCR) is the ratio of the total area of ​​photovoltaic modules in a photovoltaic array to the area occupied by the photovoltaic array.

[0006] It should be noted that the reason for adjusting the photovoltaic units to a similar posture is due to the differences in the on-site installation conditions, which make the installation foundation conditions of each photovoltaic unit different. Therefore, it is not suitable to use the exact same posture. In other words, it is an optimization measure adapted to the site conditions based on the existing uniform adjustment strategy.

[0007] However, due to the large variations in solar altitude angle and solar irradiance throughout the day, the above-mentioned adjustment methods are not flexible enough and affect the power generation of the photovoltaic system. Therefore, it is necessary to design a photovoltaic system and adjustment method. Summary of the Invention

[0008] The purpose of this invention is to provide a photovoltaic system and regulation method to solve the problems mentioned in the background art.

[0009] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a photovoltaic system, the photovoltaic system comprising multiple rows of photovoltaic power generation units, the multiple rows of photovoltaic power generation units respectively constituting a first array group and a second array group, the first array group and the second array group being arranged alternately; The width of each row of photovoltaic power generation units in the first array group is greater than the width of each row of photovoltaic power generation units in the second array group; A gap is provided between the first array group and the second array group.

[0010] In some embodiments, the first array group is provided with a first attitude adjustment mechanism, which is used to adjust the attitude of each row of photovoltaic power generation units in the first array group. The second array group is provided with a second attitude adjustment mechanism, which is used to adjust the attitude of each row of photovoltaic power generation units in the second array group; Depending on the change in the solar angle, the first array group and the second array group execute uniform attitude adjustment commands, or the first array group and the second array group execute differentiated attitude adjustment commands.

[0011] It should be noted that the photovoltaic power generation units in each row of photovoltaic power generation units can be an interconnected overall structure or a relatively independent distributed structure. Therefore, the width dimension of each row of photovoltaic power generation units is the dimension in the width direction formed by considering all the photovoltaic power generation units as a whole.

[0012] In some embodiments, the first array group is provided with a first attitude adjustment mechanism, which is used to adjust the attitude of each row of photovoltaic power generation units in the first array group. The second array group is provided with a second fixing structure, which is used to keep each row of photovoltaic power generation units in the second array group in a fixed posture; preferably, the posture of each row of photovoltaic power generation units in the second array group is parallel to the mounting base surface. Based on the change in the sun's angle, the photovoltaic power generation units in the first array group are adjusted to a posture that completely blocks the photovoltaic power generation units in the second array group behind them, or the photovoltaic power generation units in the first array group are adjusted to a posture that does not block or significantly block the photovoltaic power generation units in the second array group behind them.

[0013] In a further embodiment, the first attitude adjustment mechanism is a single-axis adjustment mechanism, and the rotation axis of the single-axis adjustment mechanism is located at the lower edge of each row of photovoltaic power generation units in the first array group. The installation height of each row of photovoltaic power generation units in the second array group is consistent with the height of the lower edge of each row of photovoltaic power generation units in the first array group, and the rear side of each row of photovoltaic power generation units in the second array group is close to or attached to the lower edge of the adjacent row of photovoltaic power generation units in the first array group. A gap is provided on the front side of each row of photovoltaic power generation units in the second array group.

[0014] In some embodiments, the first array group is provided with a first fixing structure, which is used to maintain each row of photovoltaic power generation units in the first array group in a fixed posture, wherein the posture of each row of photovoltaic power generation units in the first array group is a posture that forms a first tilt angle with the mounting base surface. The second array group is provided with a second fixing structure, which is used to keep each row of photovoltaic power generation units in the second array group in a fixed posture, and the posture of each row of photovoltaic power generation units in the second array group is parallel to the mounting base surface.

[0015] In a further embodiment, the installation height of each row of photovoltaic power generation units in the second array group is consistent with the height of the lower edge of each row of photovoltaic power generation units in the first array group, and the rear side of each row of photovoltaic power generation units in the second array group is close to or abuts the lower edge of the adjacent row of photovoltaic power generation units in the first array group, and the gap is provided on the front side of each row of photovoltaic power generation units in the second array group.

[0016] In a further embodiment, the second fixing structure is a flexible fixing bracket structure.

[0017] In a further embodiment, the photovoltaic power generation units constituting the first array group and the second array group are pre-connected and assembled via a frame structure.

[0018] A method for regulating a photovoltaic system includes the following steps: S1. Determine that the multiple rows of photovoltaic power generation units in the photovoltaic system constitute a first array group and a second array group, the first array group and the second array group are arranged in an alternating manner, the ratio of the width of each row of photovoltaic power generation units in the first array group to the width of each row of photovoltaic power generation units in the second array group is greater than 1 and greater than a first threshold; wherein, at least the first array group can be attitude adjusted; and there is a gap between the first array group and the second array group. S2. Based on the row spacing between each row of photovoltaic power generation units in the first array group and the current solar angle, calculate the target attitude of the photovoltaic power generation unit in the first array group corresponding to the current solar angle; S3. Based on the current solar angle and target attitude, determine the occlusion of the second array group by the first array group; S4. If the first array group completely blocks the second array group, then each row of photovoltaic power generation units in the first array group is adjusted to the target orientation, and the second array group is hidden in the shadow formed by the first array group, so that only the first array group receives sunlight. If the first array group does not obstruct the second array group, or only partially obstructs it, then the first and second array groups are adjusted to an attitude in which they do not obstruct each other or do not significantly obstruct each other, so that the first and second array groups can jointly receive sunlight.

[0019] In a further embodiment, the first threshold is greater than or equal to 2.

[0020] Compared with the prior art, the beneficial effects achieved by the present invention are: 1. By forming a first array group and a second array group from multiple rows of photovoltaic power generation units in a photovoltaic system, and arranging the first array group and the second array group in an alternating manner, a denser arrangement of photovoltaic modules can be achieved, that is, a higher ground coverage rate (GCR). 2. By appropriately sacrificing the power generation efficiency of the second array group, the utilization rate of the site can be greatly improved, and the power generation per unit area can be effectively increased. By reducing the width of the second array group, the impact of the second array group on the overall power generation can be controlled within a reasonable range. 3. When adjusting the attitude of the first array group, two strategies are adopted according to different times: not blocking the second array group and completely blocking the second array group. This avoids the phenomenon of the second array group being partially blocked, and also eliminates "gap light" as much as possible, thereby improving the direct utilization rate of sunlight. More importantly, by reducing the size of the second array group, the attitude adjustment strategy of the first array group is made smoother, and the proportion of photovoltaic modules in the second array group that are in a relatively unfavorable attitude is reduced, thereby improving the overall benefits of the photovoltaic power station. Attached Figure Description

[0021] Figure 1 A schematic flowchart illustrating a method for regulating a photovoltaic system according to an embodiment of this disclosure; Figure 2 A top view (including a partial enlarged view) of a photovoltaic system layout provided as a first example of this disclosure; Figure 3 A top view (including a partial enlarged view) of a photovoltaic system layout provided as a second example of this disclosure; Figure 4A top view (before modification) of a photovoltaic system layout provided as a third example of this disclosure; Figure 5 A top view of a photovoltaic system layout provided as a third example of this disclosure (modified, including enlarged views of parts). Figure 6 This is a schematic diagram of the structure of the combined photovoltaic module disclosed herein (initial state). Figure 7 This is a schematic diagram of the installation effect (working state) of the combined photovoltaic modules disclosed herein. Figure 8 Comparison of optical simulation results for an adjustment method for a photovoltaic system provided in this embodiment of the present disclosure; Figure 9 This is a top view (including a magnified view) of an existing oblique single-axis adjustable photovoltaic system layout. Figure 10 This is a top view (including a magnified view) of an existing dual-axis adjustable photovoltaic system layout. Detailed Implementation

[0022] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid obscuring the invention.

[0023] It should be noted that, unless the context explicitly requires it, the words "comprising," "including," and similar terms in the entire specification and claims should be interpreted as encompassing rather than being exclusive or exhaustive; that is, meaning "including but not limited to."

[0024] Furthermore, it should be understood in the description of this disclosure that the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Additionally, in the description of this disclosure, unless otherwise stated, "a plurality of" means two or more, and "several" means one or more.

[0025] The power generation per unit area of ​​a photovoltaic system is closely related to the direct utilization rate of sunlight and the angle of incidence of sunlight.

[0026] First, direct solar utilization rate refers to the ratio of the effective area of ​​sunlight received by photovoltaic modules (front side) in a scene (i.e., scene footprint area - gap light area) to the scene footprint area, which is a dynamically changing value. Hereinafter, direct solar utilization rate will be simply referred to as Ground Using Rate (GUR), which is the ratio of the projected area of ​​photovoltaic modules on the ground in a photovoltaic array, determined by the solar altitude angle and azimuth angle, to the photovoltaic array footprint area; where projections overlap, the projected area is not counted twice, meaning GUR is always less than or equal to 1.

[0027] It should be noted that, firstly, the ground utilization rate (GUR) and ground coverage rate (GCR) are positively correlated, especially when the ground coverage rate (GCR) is low; secondly, compared with the fixed tilt system, the tracking system can dynamically obtain a higher ground utilization rate (GUR) and can better eliminate mutual shading of photovoltaic modules.

[0028] In the scenario where photovoltaic modules are completely laid flat, the ground coverage rate (GCR) is 1, and the ground utilization rate (GUR) is fixed at 1. In other cases (including fixed tilt systems and various tracking systems), the ground utilization rate GUR changes continuously in real time. Among them, as the solar angle changes, if there is "gap light", the ground utilization rate GUR is less than 1. If each photovoltaic module causes shading, the ground utilization rate GUR can be regarded as 1. However, since mutual shading will cause uncertainty, it should be avoided as much as possible. For different photovoltaic systems, when the ground utilization rate (GUR) is similar, a smaller solar incidence angle can be obtained in real time, resulting in higher power generation per unit area.

[0029] It should be noted that there are existing technologies that utilize "gap light" through bifacial photovoltaic modules, but due to complex site conditions and various engineering factors, such utilization can only play an auxiliary role and its actual contribution is not high. The technical solution of this invention is to eliminate "gap light" as much as possible, that is, to make full use of the front side of the photovoltaic module for single-sided power generation.

[0030] Because existing photovoltaic systems employ standardized design and regulation schemes, they typically reduce power generation per unit area to accommodate variations in solar altitude and azimuth throughout the year and at all times. However, with the rapid development of photovoltaic power generation projects, the scarcity of land resources and the increasing cost of land use have made improving power generation per unit area a growing concern.

[0031] The technical solution of this invention breaks through the uniform design of the prior art and adopts a differentiated staggered arrangement design and adjustment scheme, so as to better adapt to the changes in solar altitude angle and azimuth angle throughout the year and at all times.

[0032] Please see Figures 1-10 The present invention provides a technical solution: a photovoltaic system, the photovoltaic system including multiple rows of photovoltaic power generation units, the multiple rows of photovoltaic power generation units respectively forming a first array group and a second array group, the first array group and the second array group being arranged alternately; The width of each row of photovoltaic power generation units in the first array group is larger than that of each row of photovoltaic power generation units in the second array group. A gap is provided between the first array group and the second array group. The second array group is used to receive sunlight projected onto the area between the rows of photovoltaic power generation units in the first array group when the first array group cannot receive sunlight completely. A photovoltaic system includes multiple rows of photovoltaic power generation units. A row of adjustable-position photovoltaic power generation units includes several adjustable-position photovoltaic power generation units. A photovoltaic power generation unit can be a single photovoltaic module or an arrangement of multiple photovoltaic modules. When a photovoltaic power generation unit includes multiple photovoltaic modules, the multiple photovoltaic modules can be connected into one unit by a support and adjusted synchronously, or they can be adjusted in a unified manner by several independent attitude adjustment mechanisms.

[0033] In a further embodiment, the first array group is provided with a first attitude adjustment mechanism, which is used to adjust the attitude of each row of photovoltaic power generation units in the first array group. The second array group is equipped with a second attitude adjustment mechanism, which is used to adjust the attitude of each row of photovoltaic power generation units in the second array group. Depending on the change in the sun's angle, the first array group and the second array group execute the same attitude adjustment commands or execute different attitude adjustment commands.

[0034] In a further embodiment, the first array group is provided with a first fixing structure, which is used to maintain each row of photovoltaic power generation units in the first array group in a fixed posture. The posture of each row of photovoltaic power generation units in the first array group is a posture that forms a first tilt angle with the mounting base surface. The second array group is provided with a second fixing structure, which is used to keep each row of photovoltaic power generation units in the second array group in a fixed posture. The posture of each row of photovoltaic power generation units in the second array group is parallel to the mounting base surface.

[0035] In a further embodiment, depending on the change in the solar angle, each row of photovoltaic power generation units in the first array group is adjusted to a posture that completely blocks each row of photovoltaic power generation units in the second array group behind it, or each row of photovoltaic power generation units in the first array group is adjusted to a posture that does not block or significantly block each row of photovoltaic power generation units in the second array group behind it. Wherein, not significantly blocking means that the proportion of the surface area of ​​each row of photovoltaic power generation units blocking each other to the total surface is lower than a preset ratio.

[0036] Specifically, when the photovoltaic power generation units in each row do not significantly obstruct each other, the proportion of the surface area of ​​mutual obstruction between the photovoltaic power generation units in each row to the total surface is lower than a second threshold. In this disclosure, considering that different types of photovoltaic modules have different tolerances to mutual obstruction—for example, some photovoltaic modules with specific designs can still function normally when the proportion of their obstructed surface area to the total surface exceeds 30%—to fully reflect the characteristics of the technical solution of this disclosure, "not significantly obstructing" means that the proportion of the surface area of ​​mutual obstruction between the photovoltaic power generation units in each row to the total surface is lower than the second threshold. Here, the value of the second threshold can be between 10% and 30%, for example, the second threshold is 20%. Here, the total surface can be understood as the total surface area of ​​a single row of photovoltaic power generation units used to receive solar power.

[0037] In a further embodiment, the first attitude adjustment mechanism is a single-axis adjustment mechanism, and the rotation axis of the single-axis adjustment mechanism is located at the lower edge of each row of photovoltaic power generation units in the first array group; The installation height of each row of photovoltaic power generation units in the second array group is consistent with the height of the lower edge of each row of photovoltaic power generation units in the first array group, and the rear side of each row of photovoltaic power generation units in the second array group is close to or attached to the lower edge of each row of photovoltaic power generation units in the adjacent first array group. There is a gap on the front side of each row of photovoltaic power generation units in the second array group.

[0038] In a further embodiment, the second fixing structure is a flexible fixing bracket structure.

[0039] In a further embodiment, the photovoltaic power generation units constituting the first array group and the second array group are pre-connected and assembled via a frame structure.

[0040] A method for regulating a photovoltaic system includes the following steps: S1. Determine that the multiple rows of photovoltaic power generation units in the photovoltaic system constitute a first array group and a second array group, the first array group and the second array group are arranged in an alternating manner, the ratio of the width of each row of photovoltaic power generation units in the first array group to the width of each row of photovoltaic power generation units in the second array group is greater than 1 and greater than a first threshold; wherein, at least the first array group can be attitude adjusted; and there is a gap between the first array group and the second array group. S2. Based on the row spacing between each row of photovoltaic power generation units in the first array group and the current solar angle, calculate the target attitude of the photovoltaic power generation unit in the first array group corresponding to the current solar angle; S3. Based on the current solar angle and target attitude, determine the occlusion of the second array group by the first array group; S4. If the first array group completely blocks the second array group, then each row of photovoltaic power generation units in the first array group is adjusted to the target orientation, and the second array group is hidden in the shadow formed by the first array group, so that only the first array group receives sunlight. If the first array group does not obstruct the second array group, or only partially obstructs it, then the first and second array groups are adjusted to an attitude in which they do not obstruct each other or do not significantly obstruct each other, so that the first and second array groups can jointly receive sunlight.

[0041] In a further embodiment, the first threshold is greater than or equal to 2. Through calculation, when the preset ratio is 2, the above adjustment scheme can achieve a better adjustment effect; when the preset ratio is about 3, the adjustment effect of the above adjustment scheme tends to the optimal result. The value of the preset ratio is calculated and determined according to the actual application conditions.

[0042] The portion of a photovoltaic system capable of attitude adjustment can be a single-axis photovoltaic system (such as...) Figure 4 As shown), oblique single-axis photovoltaic system (such as...) Figure 9 (as shown) or a biaxial photovoltaic system (such as...) Figure 10 (as shown in the image) etc.

[0043] In actual engineering projects, the layout direction of photovoltaic systems can be adjusted according to site conditions. That is, it is not necessary to strictly follow the direction of east, south, west, and north. The installation foundation surface can be a slope or have various undulating shapes. The above factors will not have a substantial impact on the implementation of the disclosed scheme.

[0044] Single-axis tracking systems are theoretically divided into north-south axis and east-west axis. In the existing technology, the power generation of north-south axis tracking systems is slightly higher than that of east-west axis tracking systems. Therefore, north-south axis tracking systems are more common. North-south axis tracking systems mainly track the solar azimuth angle, so the tracking angle changes greatly throughout the day and requires more frequent adjustments. East-west axis tracking systems mainly track the solar altitude angle, so their advantage is that the tracking angle changes very little throughout the day and they can achieve higher power generation in winter. This invention is suitable for using an east-west axis tracking system.

[0045] In the first example, such as Figure 2 As shown, this is a ground-mounted photovoltaic power station employing a north-south axis tracking system. Specifically: the first array group is equipped with a first attitude adjustment mechanism for adjusting the attitude of each row of photovoltaic power generation units within the first array group; the second array group is equipped with a second attitude adjustment mechanism for adjusting the attitude of each row of photovoltaic power generation units within the second array group; based on changes in the solar angle, the first and second array groups execute the same attitude adjustment command, or they execute different attitude adjustment commands. Both the first and second attitude adjustment mechanisms are north-south axis single-axis adjustment mechanisms, which can adopt existing flat single-axis adjustment mechanisms, i.e., the rotation axis is located in the middle, supporting tracking angle adjustments of ±45º or ±60º.

[0046] The width of each row of photovoltaic (PV) units in the first array group (including L11, L12, L13, L14, and L15) is W1, and the width of each row of PV units in the second array group (including L21, L22, L23, and L24) is W2. The spacing between each row of PV units in the first array group is D1, and the spacing between each row of PV units in the second array group is also D1. The front and rear gaps between each row of PV units in the second array group and the adjacent rows of PV units in the first array group are both D2. The specific dimensional relationships are as follows: W1 = 3 * W2; D2 = 0.1 * W1; D1 = W1 + W2 + 2 * D2 = 4.6 * W2; The ground cover in this example is GCR1≈(W1+W2) / D1≈0.87.

[0047] It should be noted that the second array group is sandwiched within the first array group, so setting the number of rows in the second array group to be one less than the number of rows in the first array group is a reasonable choice, and this measure is also applicable to other embodiments. Furthermore, the calculated gap is based on the gap formed when all rows of photovoltaic power generation units are in their initial state (i.e., parallel to the mounting base surface).

[0048] It should be noted that large-scale photovoltaic power plants are usually composed of several photovoltaic arrays with intervals between them. This embodiment simplifies the calculation of the ground coverage rate (GCR) of the photovoltaic system by using a single photovoltaic array as the basis for calculation and ignoring the impact of the intervals between the arrays on the GCR. Of course, the impact of the intervals between the arrays is very small.

[0049] Furthermore, using the angular component a1 (hereinafter referred to as "a1") of the solar altitude angle projected onto the projection plane (AA) perpendicular to the central axis of each row of photovoltaic power generation units as the adjustment basis, with the tracking angle of the first array group being T11 and the tracking angle of the second array group being T12, then: As shown in Figure ① of the optical simulation results comparison chart, when a1 is close to 90º, the first array group and the second array group execute the same attitude adjustment command (positive tracking algorithm), and the first array group and the second array group jointly receive sunlight to generate electricity; at this time, there are some "gap light", and the ground utilization rate GUR is less than or equal to 1. As shown in Figure ② of the optical simulation results comparison chart, when a1 gradually decreases, the first array group and the second array group still execute the same attitude adjustment command (inverse tracking algorithm), and the first array group and the second array group jointly receive sunlight to generate electricity; at this time, the adjustment goal is to eliminate "gap light" as much as possible, and the ground utilization rate GUR is approximately equal to 1. As shown in Figure ③ of the optical simulation results comparison chart, when a1 is small, the first array group and the second array group execute differentiated attitude adjustment commands. The first array group receives sunlight to generate electricity, and the second array group is hidden in the shadow formed by the first array group after being illuminated by sunlight. The first array group executes the inverse tracking algorithm command that ignores the second array group. At this time, the adjustment goal is to eliminate "gap light" as much as possible, and the ground utilization rate GUR is approximately equal to 1.

[0050] In the first example, a better application effect can also be achieved by appropriately reducing the installation height of the second array group.

[0051] It should be noted that changes in the width of the photovoltaic panels do not necessarily mean that different specifications of photovoltaic modules must be produced. For example, if each row of the first array group uses three rows of photovoltaic modules laid horizontally side by side, and each row of the second array group uses a single row of photovoltaic modules laid horizontally, then a ratio of W1=3*W2 will naturally be formed.

[0052] In the second example, such as Figure 3As shown, a rooftop photovoltaic system employs an east-west axis (partial) tracking system. The roof can be a flat roof or a pitched roof, with a flat roof being the preferred choice. The same applies to ground-mounted or floating photovoltaic power plants. Specifically: the first array group is equipped with a first attitude adjustment mechanism for adjusting the attitude of each row of photovoltaic power generation units in the first array group; the second array group is equipped with a second fixing structure for maintaining each row of photovoltaic power generation units in the second array group at a fixed attitude; based on changes in the solar angle, the photovoltaic power generation units in the first array group are adjusted to a posture that completely blocks the photovoltaic power generation units in the second array group behind them, or to a posture that does not block the photovoltaic power generation units in the second array group behind them, or to a posture that does not significantly block the photovoltaic power generation units in the second array group behind them.

[0053] The first attitude adjustment mechanism is a single-axis adjustment mechanism, with the rotation axis located at the lower edge of each row of photovoltaic power generation units in the first array group; the attitude of each row of photovoltaic power generation units in the second array group is parallel to the mounting base surface, the mounting height is consistent with the height of the lower edge of each row of photovoltaic power generation units in the first array group, and the rear side is close to or fits against the lower edge of the adjacent row of photovoltaic power generation units in the first array group, and the front side of each row of photovoltaic power generation units in the second array group is provided with a gap.

[0054] The width of each row of photovoltaic power generation units in the first array group is W1, and the width of each row of photovoltaic power generation units in the second array group is W2. The spacing between each row of photovoltaic power generation units in the first array group is D1, and the spacing between each row of photovoltaic power generation units in the second array group is also D1. The front gap between each row of photovoltaic power generation units in the second array group and the adjacent two rows of photovoltaic power generation units in the first array group is D2, and the rear gap is zero or close to zero. The specific dimensional relationships are: W1 = 3 * W2; D2 = 0.1 * W1; D1 = W1 + W2 + D2 = 4.3 * W2; The ground cover in this example is GCR2≈(W1+W2) / D1≈0.93.

[0055] Here, taking into account the characteristics of the rooftop photovoltaic system, the rotation axis of the first attitude adjustment mechanism is positioned close to the roof, and a relatively small adjustment range can be used, such as a tracking angle of 0-30º. This improves safety, achieves a higher GCR, and provides higher power generation per unit area compared to other rooftop installation methods.

[0056] It should be noted that, to adapt to rooftop application conditions, lightweight photovoltaic modules should be used, and the width of each row of photovoltaic modules should be minimized to reduce the design complexity and operational risks of the regulation mechanism. Therefore, the dimensions of the second array group need to be smaller than those of conventional modules. However, changing the dimensions is relatively easier when using lightweight photovoltaic modules.

[0057] Furthermore, using the angular component a1 (hereinafter referred to as "a1") of the solar altitude angle projected onto the projection plane (AA) perpendicular to the central axis of each row of photovoltaic power generation units as the adjustment basis, with the tracking angle of the first array group being T21 and the fixed installation angle of the first array group being T22=0º, then: As shown in Figure ④ of the optical simulation results comparison chart, when a1 is close to 90º, the first array group executes the positive tracking algorithm command, and the first and second array groups jointly receive sunlight to generate electricity; at this time, there are some "gap lights", and the ground utilization rate GUR is less than or equal to 1. As shown in Figure ⑤ of the optical simulation results comparison chart, when a1 gradually decreases, the first array group executes the inverse tracking algorithm command to not block the second array group; the first array group and the second array group jointly receive sunlight to generate electricity; at this time, the adjustment goal is to eliminate "gap light" as much as possible, and the ground utilization rate GUR is approximately equal to 1. As shown in Figure ⑥ of the optical simulation results comparison chart, when a1 is small, only the first array group is used to receive sunlight to generate electricity, and the second array group is hidden in the shadow formed by the first array group after being illuminated by sunlight. The first array group executes the inverse tracking algorithm command that ignores the second array group. At this time, the adjustment goal is to eliminate "gap light" as much as possible, and the ground utilization rate GUR is approximately equal to 1.

[0058] It should be noted that the main difference between the first and second examples lies in whether the second array group can be tracked and adjusted. Because the second array group is subordinate and has a smaller size, the benefits of tracking and adjusting it are relatively low; therefore, the second example is a better choice in terms of overall performance, simplifying the system structure and control logic.

[0059] This example primarily applies to distributed photovoltaic systems, i.e., rooftops of various buildings, especially flat roofs.

[0060] Taking this example, since the rear edge of the photovoltaic power generation unit in the second array group is close to or abuts the lower edge of the photovoltaic power generation unit in the adjacent first array group, in specific implementation, the first and second photovoltaic power generation units constituting the first and second array groups can be pre-connected and assembled through an outer frame structure to form a combined photovoltaic module. The combined photovoltaic module is easy to transport and can be installed using an installation process similar to that of ordinary photovoltaic modules, reducing on-site assembly workload; only gaps need to be reserved between rows during installation.

[0061] For example, such as Figure 6 As shown, the modular photovoltaic module includes an outer frame structure 13, a first photovoltaic power generation unit 11, a second photovoltaic power generation unit 12, and a rotating shaft 14. The second photovoltaic power generation unit, the rotating shaft, and the first photovoltaic power generation unit are fixedly installed in sequence within the outer frame structure. The rotating shaft is used to drive the first photovoltaic power generation unit to rotate around its bottom axis.

[0062] like Figure 7 As shown, during installation, several modular photovoltaic modules are arranged and combined using an outer frame structure. Several first photovoltaic power generation units are combined to form a first array group, and several second photovoltaic power generation units are combined to form a second array group. The first array group can be rotated to adjust its attitude. A gap D2 is maintained between each row of the first array group and the second array group.

[0063] The third example primarily focuses on the retrofitting and upgrading of existing fixed ground-mounted photovoltaic power stations. For example... Figure 4 As shown (including L11, L12, L13, L14, and L15), in existing fixed ground-mounted photovoltaic power stations, according to the photovoltaic power station design specifications, "the spacing between rows and columns of photovoltaic arrays should ensure that there is no shading between the front, back, left, and right sides during the period from 9:00 to 15:00 (local true solar time) each day." Considering the most unfavorable conditions on the winter solstice, the design value for the spacing is relatively large, and the GCR value is generally around 0.5. Based on this, if... Figure 5 As shown, an existing array can be set as the first array group, and a second array group can be added to it to improve land utilization.

[0064] like Figure 5As shown, the first array group (including L11, L12, L13, L14, and L15) is equipped with a first fixing structure to maintain each row of photovoltaic power generation units in the first array group in a fixed posture. The posture of each row of photovoltaic power generation units in the first array group is a posture that forms a first tilt angle with the mounting base surface. The second array group (including L21, L22, L23, and L24) is equipped with a second fixing structure to maintain each row of photovoltaic power generation units in the second array group in a fixed posture. The posture of each row of photovoltaic power generation units in the second array group is a posture that is parallel to the mounting base surface. Furthermore, the installation height of each row of photovoltaic power generation units in the second array group is consistent with (or slightly lower than) the height of the lower edge of each row of photovoltaic power generation units in the first array group, and the rear side of each row of photovoltaic power generation units in the second array group is close to or abuts the lower edge of the adjacent row of photovoltaic power generation units in the first array group. A gap is provided on the front side of each row of photovoltaic power generation units in the second array group.

[0065] The width of each row of photovoltaic power generation units in the first array group is W1, and the width of each row of photovoltaic power generation units in the second array group is W2. The spacing between each row of photovoltaic power generation units in the first array group is D1, and the spacing between each row of photovoltaic power generation units in the second array group is also D1. The front gap between each row of photovoltaic power generation units in the second array group and the adjacent two rows of photovoltaic power generation units in the first array group is D2, and the rear gap is close to zero or equal to zero (this rear gap is ignored in the following calculations). The specific dimensional relationships are: GCR3a represents the initial ground coverage of the photovoltaic array, which is set to 0.5 according to existing design specifications. The first array group adopts a fixed south tilt angle (Northern Hemisphere), where the fixed tilt angle is 30º. D1 = W1 / GCR3a = 2 * W1; W1 = 3 * W2; D2 = D1 - W1 - W2 = 2 * W2; Therefore, after adding the second array group, the ground coverage rate of the new system is GCR3b≈(W1+W2) / D1≈0.67, which is 33% more photovoltaic modules than the initial system, and the power generation increases by about 20%.

[0066] Furthermore, in this example, each photovoltaic power generation unit maintains a fixed orientation, and the analysis is based on the angular component a1 (hereinafter referred to as "a1") of the solar altitude angle projected onto the projection plane (AA) perpendicular to the central axis of each row of photovoltaic power generation units: As shown in Figure ⑦ of the optical simulation results comparison chart, when a1 is close to 90º, the first array group and the second array group jointly receive sunlight to generate electricity; at this time, there are some "gap lights", and the ground utilization rate GUR is less than or equal to 1. As shown in Figure ⑧ of the optical simulation results comparison chart, when a1 gradually decreases, the first array group and the second array group jointly receive solar power; during this period, the first array group does not cause mutual shading or significant mutual shading to the second array group; the ground utilization rate GUR is approximately equal to 1. As shown in Figure 9 of the optical simulation results comparison chart, when a1 is small, only the first array group receives sunlight to generate electricity, and the second array group is hidden in the shadow formed by the first array group after being illuminated by sunlight, resulting in a ground utilization rate (GUR) of approximately 1. Then, the power generation will rapidly decrease until the rows of photovoltaic power generation units in the first array group significantly shade each other.

[0067] It should be noted that when both the first and second array groups are installed at a fixed angle, photovoltaic modules with a high tolerance for shading should be used to reduce the adverse effects caused by the inability to dynamically adjust the tilt angle of the photovoltaic modules.

[0068] Furthermore, in this example, the design of using a smaller width for each row of photovoltaic power generation units in the second array group is of great significance. This is because it can minimize the time period during which the second array group is partially shaded in a fixed photovoltaic system, thereby reducing its impact.

[0069] When modifying existing projects, in order to reduce workload and minimize conflicts and impacts on the existing system, the second fixed structure adopted by the second array group is a flexible fixed support structure. This avoids construction such as piling and burying supports in the existing array. Only a prestressed cable structure needs to be erected on the periphery of the photovoltaic array, thereby minimizing the impact on the existing system.

[0070] Furthermore, given the rapid pace of technological advancements in photovoltaic modules, to maximize the effectiveness of technological upgrades, the first array group can be prioritized for replacement with new photovoltaic modules. The dismantled old modules can then be used to construct the second array group, eliminating the need to scrap them. Since the utilization rate of the second array group is relatively lower than that of the first, this upgrade not only better utilizes the first array group but also ensures that the lifespans of both array groups are more consistent, thus achieving optimal performance.

[0071] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and all such equivalent transformations fall within the protection scope of the present invention.

Claims

1. A photovoltaic system, characterized in that: The photovoltaic system includes multiple rows of photovoltaic power generation units, which respectively constitute a first array group and a second array group, and the first array group and the second array group are arranged alternately. The width of each row of photovoltaic power generation units in the first array group is greater than the width of each row of photovoltaic power generation units in the second array group; A gap is provided between the first array group and the second array group.

2. The photovoltaic system according to claim 1, characterized in that: The first array group is provided with a first attitude adjustment mechanism, which is used to adjust the attitude of each row of photovoltaic power generation units in the first array group; The second array group is provided with a second attitude adjustment mechanism, which is used to adjust the attitude of each row of photovoltaic power generation units in the second array group; Depending on the change in the solar angle, the first array group and the second array group execute uniform attitude adjustment commands, or the first array group and the second array group execute differentiated attitude adjustment commands.

3. A photovoltaic system according to claim 1, characterized in that: The first array group is provided with a first attitude adjustment mechanism, which is used to adjust the attitude of each row of photovoltaic power generation units in the first array group; The second array group is provided with a second fixing structure, which is used to keep each row of photovoltaic power generation units in the second array group in a fixed posture; Based on the change in the sun's angle, the photovoltaic power generation units in the first array group are adjusted to a posture that completely blocks the photovoltaic power generation units in the second array group behind them, or the photovoltaic power generation units in the first array group are adjusted to a posture that does not block or significantly block the photovoltaic power generation units in the second array group behind them.

4. A photovoltaic system according to claim 1, characterized in that: The first array group is provided with a first fixing structure, which is used to maintain each row of photovoltaic power generation units in the first array group in a fixed posture. The posture of each row of photovoltaic power generation units in the first array group is a posture that forms a first tilt angle with the mounting base surface. The second array group is provided with a second fixing structure, which is used to keep each row of photovoltaic power generation units in the second array group in a fixed posture, and the posture of each row of photovoltaic power generation units in the second array group is parallel to the mounting base surface.

5. A photovoltaic system according to claim 3, characterized in that: The first attitude adjustment mechanism is a single-axis adjustment mechanism, and the rotation axis of the single-axis adjustment mechanism is set at the lower edge of each row of photovoltaic power generation units in the first array group; The installation height of each row of photovoltaic power generation units in the second array group is consistent with the height of the lower edge of each row of photovoltaic power generation units in the first array group, and the rear side of each row of photovoltaic power generation units in the second array group is close to or attached to the lower edge of the adjacent row of photovoltaic power generation units in the first array group. A gap is provided on the front side of each row of photovoltaic power generation units in the second array group.

6. A photovoltaic system according to claim 4, characterized in that: The installation height of each row of photovoltaic power generation units in the second array group is consistent with the height of the lower edge of each row of photovoltaic power generation units in the first array group, and the rear side of each row of photovoltaic power generation units in the second array group is close to or abuts the lower edge of the adjacent row of photovoltaic power generation units in the first array group. The gap is provided on the front side of each row of photovoltaic power generation units in the second array group.

7. A photovoltaic system according to claim 3 or 4, characterized in that: The second fixing structure is a flexible fixing bracket structure.

8. A photovoltaic system according to claim 3 or 4, characterized in that: The photovoltaic power generation units that make up the first array group and the second array group are pre-connected and assembled through a frame structure.

9. A method for regulating a photovoltaic system, characterized in that: Includes the following steps: S1. Determine that the multiple rows of photovoltaic power generation units in the photovoltaic system constitute a first array group and a second array group, the first array group and the second array group are arranged in an alternating manner, the ratio of the width of each row of photovoltaic power generation units in the first array group to the width of each row of photovoltaic power generation units in the second array group is greater than 1 and greater than a first threshold; wherein, at least the first array group can be attitude adjusted; and there is a gap between the first array group and the second array group. S2. Based on the row spacing between each row of photovoltaic power generation units in the first array group and the current solar angle, calculate the target attitude of the photovoltaic power generation unit in the first array group corresponding to the current solar angle; S3. Based on the current solar angle and target attitude, determine the occlusion of the second array group by the first array group; S4. If the first array group completely blocks the second array group, then each row of photovoltaic power generation units in the first array group is adjusted to the target orientation, and the second array group is hidden in the shadow formed by the first array group, so that only the first array group receives sunlight. If the first array group does not obstruct the second array group, or only partially obstructs it, then the first and second array groups are adjusted to an attitude in which they do not obstruct each other or do not significantly obstruct each other, so that the first and second array groups can jointly receive sunlight.

10. A method for regulating a photovoltaic system according to claim 9, characterized in that: The first threshold is greater than or equal to 2.

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