JP2015228736A - Photovoltaic power generation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photovoltaic power generation system capable of implementing cost reduction while ensuring safety.SOLUTION: The photovoltaic power generation system includes a solar cell array group including a plurality of solar cell arrays. An inclination angle of at least one of the solar cell arrays positioned at both ends of the solar cell array group is larger than an inclination angle of any other solar cell array of the solar cell array group.

Description

  Embodiments described herein relate generally to a large-scale photovoltaic power generation system.

  In recent years, due to consideration for environmental issues, the introduction of solar power generation systems that generate power using sunlight has increased worldwide, and mega solar power plants with large-scale solar power generation systems are being constructed around the world. . In the photovoltaic power generation system, a stand (including a foundation) for supporting and fixing a large number of solar battery panels is necessary. The ratio of costs related to the base (material costs, construction costs, etc.) in the total construction cost of the solar power generation system is large, especially in the case of a solar power generation system in which 10,000 or more solar panels are arranged. It gets bigger and bigger. Therefore, it is required to reduce the cost of the gantry while ensuring the safety of the gantry.

JP 2004-225280 A JP 2003-124495 A JP 2011-181670 A

  The problem to be solved by the present invention is to provide a solar power generation system capable of realizing cost reduction while ensuring safety.

  A photovoltaic power generation system according to an embodiment includes a solar cell array group including a plurality of solar cell arrays. The inclination angle of at least one of the solar cell arrays located at both ends of the solar cell array group is larger than the inclination angle of the other solar cell array in the solar cell array group.

1 is a top view schematically showing a solar power generation system according to one embodiment. The side view which shows roughly the one solar cell array contained in the solar energy power generation system shown in FIG. The side view which shows roughly the solar energy power generation system which concerns on the 1st example of 1st Embodiment. The figure which shows the simulation result regarding the flow of a wind in case a wind blows from the back to the solar cell array group in which the solar cell array was installed with the inclination angle of 30 degrees. FIG. 5 is a diagram schematically showing the simulation result shown in FIG. 4. The contour figure which shows the simulation result regarding the flow of a wind in case a wind blows from the back to the solar cell array group in which the solar cell array was installed with the inclination angle of 5 degrees. The contour figure which shows the simulation result regarding the flow of a wind in case a wind blows from the back to the solar cell array group in which the solar cell array was installed with the inclination angle of 10 degrees. The contour figure which shows the simulation result regarding the flow of a wind in case a wind blows from the back to the solar cell array group in which the solar cell array was installed with the inclination angle of 15 degrees. The figure which shows the simulation result shown in FIG. 7 typically. The contour figure which shows the result of having simulated the flow of the wind which blows on a barrier. The side view which shows roughly the solar energy power generation system which concerns on the 2nd example of 1st Embodiment. The side view which shows roughly the solar energy power generation system which concerns on the 3rd example of 1st Embodiment. The side view which shows an example of the method of implement | achieving the photovoltaic power generation array which has an inclination angle larger than the inclination angle of another solar cell array. The side view which shows the other example of the method of implement | achieving the photovoltaic power generation array which has an inclination angle larger than the inclination angle of another solar cell array. The side view which shows the further another example of the method of implement | achieving the photovoltaic power generation array which has an inclination angle larger than the inclination angle of another solar cell array. The top view which shows roughly the solar energy power generation system which concerns on other embodiment. The side view which shows roughly the solar energy power generation system which concerns on 2nd Embodiment.

  Hereinafter, embodiments will be described with reference to the drawings. In the following embodiments, the same components are denoted by the same reference numerals, and repeated description is omitted.

(First embodiment)
FIG. 1 is a top view schematically showing the photovoltaic power generation system according to the first embodiment. The solar power generation system shown in FIG. 1 includes a solar cell array group 10 including a plurality of solar cell arrays 11. In the example of FIG. 1, the solar cell array group 10 includes six solar cell arrays 11-1 to 11-6, and these solar cell arrays 11-1 to 11-6 are equal in width W, and both ends are It arrange | positions with the space | interval L in the state which prepared. Here, the width W is a dimension in a direction orthogonal to the direction in which the solar cell arrays 11-1 to 11-6 are arranged. Each of the solar cell arrays 11-1 to 11-6 includes a plurality of solar cell panels 12 that convert sunlight into electric power. In FIG. 1, each rectangular block represents one solar cell panel 12. In each of the solar cell arrays 11-1 to 11-6, ten solar cell panels 12 connected by a conductive connection member are linearly arranged.

  FIG. 2 is a side view schematically showing one of the solar cell arrays 11-1 to 11-6. As shown in FIG. 2, the solar cell panel 12 is supported by the gantry 20. The gantry 20 is fixed to the ground G by the foundation 30. The gantry 20 includes an attachment portion 21 for attaching the solar cell panel 12, a support 22, and a lateral member 23. The attachment portion 21 is supported and fixed by a support column 22. The struts 22 are fixed to the foundation 30 using, for example, anchor bolts, and are coupled to each other by a lateral member 23. The mounting portion 21 includes, for example, a frame-shaped support base 24 and a mounting bar 25 that is horizontally mounted on the support base 24. Bolt holes for passing bolts are formed in the mounting bar 25. Bolt holes through which the bolts are passed are also formed in the frame attached to the back surface 14 of the solar cell panel 12. With the bolt holes of the frame of the solar cell panel 12 and the bolt holes of the mounting bar 25 aligned, the bolts are inserted into the bolt holes and engaged with engaging members such as nuts, so that the solar cell panel 12 is mounted on the base. 20 is fixed.

  In general, the solar cell panel 12 is installed at an inclination from the viewpoint of power generation efficiency. For example, in a high latitude region in the northern hemisphere such as Japan, the solar cell panel 12 is fixed to the gantry 20 with the light receiving surface 13 inclined toward the south. That is, the solar cell array 11 is installed facing south. The inclination angle of the solar cell array 11, that is, the angle (elevation angle) θ formed between the horizontal plane and the light receiving surface 13 of the solar cell panel 12 is determined in consideration of various conditions such as the latitude of the installation location and the environment.

  In this embodiment, the case where the solar cell array 11 is installed southward is assumed. Here, the direction in which the plurality of solar cell arrays 11 are arranged is defined as the front-rear direction, and the direction in which the light receiving surface 13 of the solar cell array 11 is directed (south side in the present embodiment) is the front. In the example shown in FIG. 1, the solar cell arrays 11-1 to 11-6 are such that the solar cell array 11-1 is located at the north end (rear end) of the solar cell array group 10, and further the solar cell array 11-6. Are arranged side by side in the north-south direction so as to be located at the south end (front end) of the solar cell array group 10. In each of the solar cell arrays 11-1 to 11-6, the direction in which the solar cell panels 12 are arranged corresponds to the east-west direction.

  In the photovoltaic power generation system according to this embodiment, the inclination angle of at least one of the solar cell arrays 11 of the solar cell array 11 positioned at both ends of the solar cell array group 10 is another solar cell array in the solar cell array group 10. It is designed to be larger than 11 inclination angles. Here, the solar cell arrays 11 positioned at both ends of the solar cell array group 10 indicate the solar cell arrays 11 positioned on the outermost side in the direction in which the solar cell arrays 11 are arranged. In the example where the solar cell arrays 11-1 to 11-6 as shown in FIG. 1 are arranged in the north-south direction, the solar cell arrays 11 located at both ends of the solar cell array group 10 are the solar cell arrays 11- at the north end. 1 and the solar cell array 11-6 at the south end.

  In Japan, the gantry is usually designed according to JIS C8955 (2004), which is a design guide on structures for photovoltaic array established by Japanese Industrial Standards. According to JIS C8955 (2004), a fixed load due to the mass of a solar cell array (a plurality of solar cell panels arranged and wired), a wind load due to wind pressure, a snow load due to snow accumulated on the surface of the solar cell panel, and an earthquake due to seismic force It is stipulated that the gantry should be designed after assuming four types of loads. Although the combination of these loads varies depending on the installation environment, the wind pressure load is a load that must be considered in many photovoltaic power plants. According to JIS C8955 (2004), the wind pressure load is calculated according to the following formula (1).

Here, W _p is a wind pressure load (N), C _w is a wind force coefficient, q _p is a wind speed pressure (N / m ² ), and A _w is a wind receiving area (m ² ). . In the embodiment in which the solar cell array 11 is installed on the ground, the wind force coefficient _Cw is calculated according to an approximate expression using the inclination angle of the solar cell array as a parameter. Wind pressure q _p is determined according to the installation environment. JIS C8955 (2004) states that in the form of ground installation, when there are a plurality of mounts, the value of the approximate expression may be used for the peripheral edge and the value of the approximate expression may be used for the central part. It is described. In JIS C8955 (2004), there is no clear description about the division of the peripheral end portion and the central portion. In the case where no windbreak countermeasures are taken, considering safety, for example, it is appropriate to consider the region 51 shown in FIG. 1 as the central portion. In the photovoltaic power generation system according to the present embodiment, a windproof effect as described later can be obtained by increasing the inclination angle of at least one of the solar cell arrays 11 located at both ends of the solar cell array group 10. For this reason, safety can be ensured even if the region 52 wider than the region 51 is regarded as the central portion. The region 52 includes, for example, solar cell arrays 11-2 to 11-5 excluding the solar cell arrays 11-1 and 11-6 located at both ends of the solar cell array group 10. When the area that can be regarded as the central portion is widened, the gantry 20 and the foundation 30 can be reduced in weight, and the costs related to the gantry 20 and the foundation 30 can be reduced.

FIG. 3 is a side view schematically showing the photovoltaic power generation system according to the first example of the present embodiment. In FIG. 3, the gantry 20 and the foundation 30 are omitted. In the photovoltaic power generation system shown in FIG. 3, the solar cell array group 10 includes N solar cell arrays 11-1 to 11 -N installed in the south direction. Here, N is an integer of 3 or more. The inclination angles of the solar cell array 11-1 at the north end and the solar cell array 11-N at the south end are arranged in the middle part of the solar cell array group 10, that is, the solar cell array 11-1 and the solar cell array 11-N. It is larger than the inclination angle of the solar cell arrays 11-2 to 11- (N-1) disposed between the two. Typically, the inclination angles of the solar cell arrays 11-2 to 11- (N-1) are equal to each other. In this case, when the inclination angles of the solar cell arrays 11-1 to 11-N are expressed as θ ₁ to θ _N , θ ₁ > θ ₂ , θ _N > θ ₂ , θ ₂ = θ ₃ =... = Θ _{N -1} . Inclination angle theta ₁ of the solar cell array 11-1 may be equal to the inclination angle theta _N of solar battery array 11-N, may be different.

  FIG. 4 shows the result of simulating the flow of wind when a cross wind blows from behind to the solar cell array group 10 in which the solar cell array 11 is installed at an inclination angle of 30 °. FIG. 5 schematically shows a wind flow based on the simulation result shown in FIG. In the simulation, the gantry 20 and the foundation 30 are not considered because the influence on the wind flow is small. As shown in FIGS. 4 and 5, the wind flow is blocked by the solar cell array 11-1 at the rear end, and the wind direction is changed. As a result, a wide stagnation region 60 is generated in the lee of the solar cell array 11-1, and the wind does not directly hit the solar cell array 11-2.

  6, 7, and 8 show results of simulating the flow of wind blown from the rear toward the solar cell array 11 when the inclination angle of the solar cell array 11 is 5 °, 10 °, and 15 °. . In FIG. 6, FIG. 7 and FIG. 8, contours showing a flow velocity of 20 m / s in the lee of the solar cell array 11 are highlighted by broken lines. The inside of the broken line is a region where the flow velocity is 20 m / s or less. 6, 7, and 8, it can be seen that the region where the flow velocity is relatively low in the lee of the solar cell array 11 becomes wider as the inclination angle increases, as indicated by the double-headed arrow. In particular, when the inclination angle is 15 °, the separation of the wind by the solar cell array 11 occurs, and as a result, the region where the flow velocity is low is dramatically widened. FIG. 9 schematically shows a wind flow based on the simulation result shown in FIG. As shown in FIG. 9, the wind flow is not sufficiently blocked by the solar cell array 11-1, and the wind direction is slightly changed. Therefore, the stagnation region 60 generated in the lee of the solar cell array 11 is small, and the wind directly hits the solar cell array 11-2. As a result, the wind pressure load acting on the solar cell array 11-2 does not become 1/2 or less of the wind pressure load of the solar cell array 11-1.

  From the simulation results shown in FIGS. 4, 6, 7, and 8, if the inclination angle of the solar cell array 11 is 15 ° or more, the other solar cell array 11 positioned leeward of the solar cell array 11. It can be seen that a sufficient windproof effect for the solar cell array 11 can be obtained, that is, the wind pressure acting on the other solar cell array 11 located leeward can be sufficiently reduced.

FIG. 10 shows the result of simulating the flow of wind blowing on the barrier with height h. This simulation corresponds to the case where the inclination angle of the solar cell array 11 is 90 °. FIG. 10 shows that the windbreak effect by the solar cell array can be obtained up to the vicinity of the distance of 5.5 × h from the barrier. The height h of the barrier can be regarded as the maximum height of the solar cell array 11. Therefore, the pitch between the end solar cell array 11 and the solar cell array 11 adjacent to the end solar cell array 11 is desirably 5.5 times or less the maximum height of the end solar cell array 11. As shown in FIG. 3, the pitch between the solar cell array 11-1 at the rear end and the solar cell array 11-2 adjacent to the rear end solar cell array 11-1 is the rear end (position of the maximum height). from the corresponding) to point to the horizontal distance L ₁ to the rear end of the solar cell array 11-2. The pitch between the solar cell array 11-N at the front end and the solar cell array 11- (N-1) adjacent thereto is from the rear end (corresponding to the position of the maximum height) of the solar cell array 11-N. The horizontal distance L to the front end of the solar cell array 11- (N-1) is indicated.

FIG. 11 is a side view schematically showing a photovoltaic power generation system according to the second example of the present embodiment. In FIG. 11, the gantry 20 and the foundation 30 are omitted. In the solar power generation system shown in FIG. 11, solar cell array group 10 includes M solar cell arrays 11-1 to 11 -M installed in the south direction. Here, M is an integer of 2 or more. Inclination angle theta _M of the southern tip of the solar cell array 11-M is larger than the inclination angle θ ₁ ~θ _M-1 of the solar cell array 11-1~11- (M-1). In the second example, typically, the inclination angle θ ₁ ~θ _M-1 of the solar cell array 11-1~11- (M-1) are equal to each other. That is, θ _M > θ ₁ = θ ₂ =... = Θ _M−1 . In the solar power generation system shown in FIG. 11, the south wind is effectively blocked by the solar cell array 11 -M at the south end, so that the wind pressure acting on the solar cell arrays 11-1 to 11-(M−1) is reduced. can do.

FIG. 12 is a side view schematically showing a photovoltaic power generation system according to the third example of the present embodiment. In FIG. 12, the gantry 20 and the foundation 30 are omitted. In the solar power generation system shown in FIG. 12, the solar cell array group 10 includes M solar cell arrays 11-1 to 11-M installed in the south direction. Inclination angle theta ₁ of the northern end of the solar cell array 11-1 is larger than the inclination angle θ ₂ ~θ _M-1 of the solar cell array 11-2~11- (M-1). In a third example, typically, the inclination angle theta ₂ through? _M of the solar cell array 11-2 to 11-M are equal to each other. That is, θ ₁ > θ ₂ = θ ₃ =... = Θ _M. In the photovoltaic power generation system shown in FIG. 12, the north wind is effectively blocked by the solar cell array 11-1 at the northern end, so that the wind pressure acting on the solar cell arrays 11-2 to 11-M can be reduced.

  In general, when the solar cell array 11 is installed at an inclination, the wind from the rear acts a larger wind pressure on the solar cell array 11 than the wind from the front. For this reason, the form (3rd example) which makes the inclination angle of the solar cell array 11 of a rear end larger than the form (2nd example) which makes the inclination angle of the solar cell array 11 of a front end larger.

  One method of installing a solar power generation system is a method of assembling a solar cell panel, a gantry, and a foundation at a factory, and transporting an assembly (referred to as a solar cell unit) to an installation location. When this method is used, solar cell units having different inclination angles of solar cell panels are usually prepared. Instead, as shown in FIG. 13, the ground G is dug diagonally, and a solar cell unit in which the solar cell panel is fixed at a normal inclination angle is installed there, so that it is more than other solar cell arrays. The solar cell array 11 may be installed with a large inclination angle. In another example, as shown in FIG. 14, by using a foundation 30 in which a cross section perpendicular to the width direction (east-west direction) is formed in a substantially trapezoidal shape, the solar cell unit is more than the other solar cell array. The solar cell array 11 may be installed with a large inclination angle. These examples have the advantage that the gantry 20 having the same structure as other solar cell arrays can be used. In yet another example, a solar cell unit in which a plurality of solar cell panels are fixed to a gantry at different inclination angles is prepared. Specifically, as shown in FIG. 15, the solar cell panel 12B is fixed to the gantry 20 at the same angle as the inclination angle of the other solar cell array, and the solar cell panel 12A is determined from the inclination angle of the other solar cell array. Is fixed to the gantry 20 at a large angle. The solar cell panel 12A is located on the rear side of the solar cell panel 12B, and the lower end of the solar cell panel 12A is opposed to the upper end of the solar cell panel 12B.

  In addition, arrangement | positioning of the solar power generation system which concerns on this embodiment is not limited to the example of arrangement | positioning of the solar cell array 11 shown by FIG. For example, as shown in FIG. 16, the photovoltaic power generation system may have a different width for each solar cell array. More specifically, the solar cell array 11-2 is wider than the solar cell array 11-1, and the solar cell array 11-3 is wider than the solar cell array 11-2. The battery array 11 has a larger width in front (south side). On the contrary, the solar cell array 11 may have a smaller width toward the front (south side).

  As described above, in the solar power generation system according to the present embodiment, the inclination angle of at least one of the solar cell arrays positioned at both ends of the solar cell array group is the other sun of the solar cell array group. It is larger than the inclination angle of the battery array. Thereby, the wind pressure which acts on the solar cell array located in the center part of a solar cell array group is reduced. As a result, cost reduction of the foundation and the gantry can be realized while ensuring safety.

(Second Embodiment)
FIG. 17 is a side view schematically showing a photovoltaic power generation system according to the second embodiment. In FIG. 17, the gantry and the foundation are omitted. The solar power generation system shown in FIG. 17 includes a solar cell array group 10, and this solar cell array group 10 includes M solar cell arrays 11-1 to 11-M arranged in the south direction. The photovoltaic power generation system according to the present embodiment is designed so that the inclination angle of the solar cell array 11-1 at the northern end is smaller than the inclination angles of the other solar cell arrays 11-2 to 11-M. In this design, the wind pressure acting on the solar cell arrays 11-1 to 11-M is made uniform. Therefore, it is possible to make the strength of the bases and foundations of the solar cell arrays 11-1 to 11-M uniform, and to make the bases and base materials common to all the solar cell arrays 11-1 to 11-M. Can do. As a result, cost can be reduced.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 10 ... Solar cell array group, 11 ... Solar cell array, 12 ... Solar cell panel, 13 ... Light-receiving surface, 14 ... Back surface, 20 ... Mount, 21 ... Mounting part, 22 ... Support | pillar, 23 ... Cross member, 24 ... Support stand 25 ... Mounting bars, 30 ... Basics.

Claims (9)

A solar cell array group including a plurality of solar cell arrays;
The sun, wherein an inclination angle of at least one of the solar cell arrays located at both ends of the solar cell array group is larger than an inclination angle of another solar cell array in the solar cell array group. Photovoltaic system.   The solar power generation system according to claim 1, wherein the at least one solar cell array is a solar cell array located at a rear end of the solar cell array group.   2. The sunlight according to claim 1, wherein the plurality of solar cell arrays are installed facing south, and the at least one solar cell array is a solar cell array positioned at a north end of the solar cell array group. Power generation system.   The solar power generation system according to any one of claims 1 to 3, wherein an inclination angle of the at least one solar cell array is 15 ° or more.   The pitch between the at least one solar cell array and the solar cell array adjacent to the at least one solar cell array is not more than 5.5 times the maximum height of the at least one solar cell array. The photovoltaic power generation system according to any one of claims 1 to 4. A gantry supporting the at least one solar cell array;
A foundation for fixing the mount to the ground;
Further comprising
The said foundation is provided in the said ground dug diagonally, The solar power generation system as described in any one of the Claims 1 thru | or 5 characterized by the above-mentioned. A gantry supporting the at least one solar cell array;
A foundation for fixing the gantry to the ground, and a foundation in which a cross-sectional shape orthogonal to the width direction is formed in a substantially trapezoidal shape;
The solar power generation system according to any one of claims 1 to 5, further comprising: A gantry supporting the at least one solar cell array;
A foundation for fixing the mount to the ground;
Further comprising
The at least one solar cell array includes a first solar cell panel supported by the mount at the same angle as an inclination angle of the other solar cell array, and an angle larger than the inclination angle of the other solar cell array. A solar power generation system according to any one of claims 1 to 5, further comprising a second solar cell panel supported by the gantry.   The solar power generation system according to any one of claims 1 to 8, wherein the plurality of solar cell arrays have a larger width as they are positioned forward.