JP2015153055A - Solar power generation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve simplification and improvement of maintenance workability in a biaxial tracking drive system of a solar power generation device.SOLUTION: Both of azimuth angle adjustment and elevation angle adjustment of a solar panel 40 are performed by fluid pressure type linear driving devices 60 and 110.

Description

  The present invention relates to a solar power generation device, and more particularly to a two-axis tracking solar power generation device that performs solar tracking by adjusting an elevation angle and an azimuth angle of a solar panel.

  The two-axis tracking type solar power generation apparatus has an elevation angle that is an inclination angle around the horizontal axis of the solar panel and the solar panel according to the height and direction of the solar panel so that the light-receiving surface of the solar panel faces the sun. The azimuth, which is the rotation angle around the vertical line, is automatically adjusted.

  Conventionally known two-axis tracking type solar power generation devices that perform both elevation angle adjustment and azimuth angle adjustment of a solar panel with an electric motor with a reduction gear device (for example, Patent Documents 1 and 2), There is one in which the elevation angle adjustment of the solar panel is performed by a fluid pressure cylinder device, and the azimuth angle adjustment of the solar panel is performed by an electric motor with a reduction gear device (for example, Patent Document 1).

JP-A-6-250739 Republished Patent (A1) WO2009 / 128422

  The changes in the elevation angle and azimuth angle of the sun from sunrise to sunset (sunset) are at the summer solstice, with the maximum elevation angle being about 80 degrees and the maximum azimuth angle being about 240 degrees at the latitude of Japan. For this reason, when the solar panel is tracked by the sun from sunrise to sunset, elevation angle adjustment (tilting) is performed in an angle range of about 80 degrees, and azimuth adjustment is performed in an angle range of about 240 degrees ( Rotation) needs to be performed.

  If the elevation angle adjustment is about 80 degrees, the adjustment can be performed by the fluid pressure cylinder device, but the azimuth angle adjustment rotation by the rotation angle of 180 degrees or more is performed without interference by the fluid pressure cylinder device. Is difficult.

  Therefore, in the conventional two-axis tracking type solar power generation apparatus, even if the elevation angle adjustment of the solar panel is performed by the fluid pressure cylinder device, the azimuth angle adjustment of the solar panel is performed without using the fluid pressure cylinder device. It is done with an electric motor with a device. The use of an electric motor with a reduction gear device complicates the two-axis tracking drive system of the photovoltaic power generation device, and errors due to backlash of the reduction gear device cannot be avoided and maintenance work is troublesome. become.

  The present inventor has shown that the solar position is low and the solar power generation efficiency is low at the time around sunrise or sunset, and the solar panel faces the sun at the time near sunrise or sunset. It has been found that even if azimuth adjustment is not performed, the total amount of solar power generation per day does not drop significantly.

  The problem to be solved by the present invention is to simplify the two-axis tracking drive system of the photovoltaic power generation apparatus and improve maintenance workability based on the knowledge of the inventors as described above.

  A solar power generator according to the present invention is a two-axis tracking solar power generator that performs solar tracking by adjusting the elevation angle and azimuth of a solar panel (40) having a light receiving surface (38) of a solar cell on one side. The base (10), the first shaft member (18) attached to the base (10) and rotatable about a vertical axis, and the first shaft member (18) A second shaft member (24) that is attached to support the solar panel (40) and is rotatable about a horizontal axis, and a first end that is fixed to the first shaft member (18). A swing arm (46), a second swing arm (52) having one end fixed to the second shaft member (24), and one end attached to the base (10), The other end is connected to the first swing arm (46) to change the azimuth angle of the solar panel (40). The fluid pressure type linear drive device (60), one end portion of which can be attached to the first shaft member (18), the other end portion is connected to the second swing arm (52), and the solar panel (40) ) Of the second fluid pressure type linear drive device (110) for changing the elevation angle.

  According to this configuration, since both the azimuth angle adjustment and the elevation angle adjustment of the solar panel (40) are performed by the fluid pressure type linear drive device, the biaxial tracking drive system is simplified and the maintenance workability is improved.

  In the photovoltaic power generator according to the present invention, preferably, the first fluid pressure linear drive device (60) and the second fluid pressure linear drive device (110) have the same structure.

  According to this configuration, the azimuth adjusting device and the elevation adjusting device are shared, and the number of maintenance parts can be reduced by sharing the maintenance parts.

In the photovoltaic power generator according to the present invention, preferably, the first hydraulic linear drive device (60) and the second hydraulic linear drive device (110) have pistons (78, 128), A piston (78, 128) has a first working chamber (80, 130) on one side and a piston (78, 128) on the other side has a second working chamber (82, 132). Dynamic hydraulic cylinder device (70, 120), reservoir (62, 112) for storing hydraulic oil, first discharge port (64A, 114A) and second discharge port (64B, 114B) Then, hydraulic oil is supplied from the reservoir (62, 112), and pressure oil is discharged from the first discharge port (64A, 114A) by forward rotation of the electric motor (66, 116), and the electric motor (66, 116). By reversing Bidirectional electric hydraulic pumps (64, 114) for discharging pressure oil from two discharge ports (64B, 114B), the first discharge ports (64A, 114A) and the first working chamber (80, 130) connecting the first oil passage (84, 88, 134, 138), the second discharge port (64B, 114B) and the second working chamber (82, 132). Two oil passages ( 90 , 94, 140, 144) and the first working chamber (80, 130), and the internal pressure of the first working chamber (80, 130) is not less than a first predetermined value. A first relief valve (100, 150) for returning the hydraulic oil (80, 130) of the first working chamber to the reservoir (62, 112), and the second working chamber (82, 132). The internal pressure of the second working chamber (82, 132) is And a second relief valve (102, 152) for returning the hydraulic fluid in the second working chamber (82, 132) to the reservoir (62, 112) when the second predetermined value or more is reached.

  According to this configuration, the hydraulic cylinder device (70, 120) is moved back by controlling the rotation direction of the electric motor (66, 116), and no electromagnetic switching valve is used. Improves.

  According to the photovoltaic power generation apparatus of the present invention, both the azimuth angle adjustment and the elevation angle adjustment of the solar panel are performed by the fluid pressure linear drive device, and the two-axis tracking drive system is simplified and the maintenance workability is improved. .

The side view which shows one Embodiment of the solar power generation device by this invention. The rear view of the solar power generation device by this embodiment. FIG. 3 is a sectional view taken along line III-III in FIG. 1. The mechanism figure of the azimuth angle adjustment part of the solar power generation device by this embodiment. The mechanism figure of the elevation angle adjustment part of the solar power generation device by this embodiment. The hydraulic circuit diagram of the hydraulic type linear drive device used for the solar power generation device by this embodiment.

  Hereinafter, one embodiment of a photovoltaic power generation apparatus according to the present invention will be described with reference to FIGS.

  As shown in FIGS. 1 to 3, the photovoltaic power generation apparatus has a base 10 installed on a ground base (not shown). A cylindrical post support member 12 is fixed to the central portion of the base 10 in a vertical posture (a posture in which the central axis extends in the vertical direction). The post support member 12 supports the lower end portion of a post member (first shaft member) 18 that is an orientation adjusting shaft by rolling bearings 14 and 16 so as to be rotatable (rotatable) around a vertical axis.

  The post member 18 extends in the vertical direction, and an elevation angle shaft support plate 20 is attached to the upper end portion. Bearing brackets 22 are fixed to the left and right ends of the elevation shaft support plate 20. The left and right bearing brackets 22 support a single elevation angle adjusting shaft (second shaft member) 24 extending in the horizontal direction so as to be rotatable (rotated) around a horizontal axis.

  A panel support frame 26 is fixed to the elevation adjustment shaft 24. Next, details of a fixing structure between the elevation angle adjusting shaft 24 and the panel support frame 26 will be described. The panel support frame 26 includes a rectangular frame-shaped outer frame 28, two upper and lower horizontal rails 30 that are fixed to the left and right frame portions of the outer frame 28 and extend in the horizontal direction, and both ends of the outer frame 28. The two vertical bars 31 are fixed to the upper and lower frame portions and extend in the vertical direction.

  The top and bottom leg members 32 </ b> A of a panel fixing member 32 that is U-shaped when viewed from the left and right sides are fixed to the upper and lower horizontal rails 30. The panel fixing member 32 is provided at two positions on the left and right sides, and has intermediate portions 32B that extend vertically at positions separated from the back of the panel support frame 26 by the length of the leg members 32A. A bearing sleeve 34 having a central axis that penetrates in the horizontal direction and concentric with each other is fixed to the intermediate portion 32B of the left and right panel fixing members 32.

  The left and right end portions of the elevation angle adjusting shaft 24 protrude outward in the left and right directions from the bearing bracket 22 on the corresponding side. The left and right projecting ends are fitted to the corresponding bearing sleeve 34 and fixed to the bearing sleeve 34 with a key or the like.

  A solar panel 40 having a light receiving surface 38 of a solar cell on the front surface is fixed to the front side of the panel support frame 26.

  As a result, the solar panel 40 changes the azimuth by rotating the post member 18 around the vertical axis relative to the base 10 with the central axis of the post member 18 as the rotation center, and tilts the central axis of the elevation adjustment shaft 24. The elevation angle is changed by turning the panel fixing member 32 at the center around the horizontal axis with respect to the post member 18.

  Since the panel support frame 26 and the solar panel 40 are attached to the elevation angle adjusting shaft 24 via the panel fixing member 32, the panel support frame 26 and the solar panel 40 are positioned at a position separated from the post member 18 by the length of the leg member 32A. Interference with the post member 18 is avoided in the movement of the solar panel 40 in the azimuth and elevation directions.

  Next, the two-axis tracking drive system of the azimuth angle axis and the elevation angle axis of the solar power generation device will be described.

  A first mounting bracket 42 is fixed to the base 10. The first mounting bracket 42 is connected to the base side of a hydraulic linear drive device (first fluid pressure linear drive device) 60 for adjusting the azimuth angle so as to be rotatable (pivotable) around a vertical axis by a pivot pin 44. Has been.

  A ring member 48 integrally having a first swing arm 46 is fixed to the outer peripheral portion near the lower end of the post member 18. The first swing arm 46 protrudes radially outward from the ring member 48, that is, the base end portion (one end portion) is fixed to the post member 18, and the hydraulic linear drive device 60 is provided at the protruding end portion. A pivot pin 47 is connected to the tip end portion of the piston rod 72, which is the working end, so as to be rotatable (pivotable) around the vertical axis. In this manner, the hydraulic linear drive device 60 is disposed in a substantially horizontal posture between the first mounting bracket 42 and the first swing arm 46.

  A second mounting bracket 49 is fixed near the lower end of the post member 18. The base side of a hydraulic linear drive device (second fluid pressure linear drive device) 110 for adjusting the elevation angle is connected to the second mounting bracket 49 by a pivot pin 50 so as to be rotatable (pivotable) around a horizontal axis. ing. Note that the second mounting bracket 49 is located above the ring member 48.

  A base end portion (one end portion) of the second swing arm 52 is fixed to a central portion of the elevation angle adjusting shaft 24 in the axial direction. The second swing arm 52 protrudes radially outward from the elevation adjustment shaft 24, and a protruding end portion is provided with a pivot pin 54 at a tip end portion of a piston rod 122 which is a working end of the hydraulic linear drive device 110. It is connected so as to be pivotable about a horizontal axis. In this way, the hydraulic linear drive device 110 is disposed between the second mounting bracket 49 and the second swing arm 52 in a substantially vertical posture.

  The hydraulic linear drive device 60 for adjusting the azimuth angle and the hydraulic linear drive device 110 for adjusting the elevation angle have the same structure, and reservoirs 62 and 112 (see FIG. 6) for storing hydraulic oil are integrated. The hydraulic cylinder devices 70 and 120 having the bidirectional hydraulic pumps 64 and 114, the electric motors 66 and 116 that drive the hydraulic pumps 64 and 114 to rotate forward and reverse, the valve cases 68 and 118, and the piston rods 72 and 122. It is comprised by the assembly. The hydraulic linear drive devices 60 and 110 are configured so that the pivot pins 44 and 50 pass through the base end portions of the hydraulic cylinder devices 70 and 120 (the side opposite to the side from which the piston rods 72 and 122 protrude). The connecting piece portions 74 and 124 that form attachment portions for the first attachment bracket 42 and the second attachment bracket 49 are integrally provided.

  Next, a hydraulic circuit of the hydraulic linear drive devices 60 and 110 will be described with reference to FIG. The hydraulic circuit of the hydraulic linear drive device 60 and the hydraulic circuit of the hydraulic linear drive device 110 have exactly the same structure.

  The hydraulic pumps 64 and 114 are constituted by bidirectional gear pumps or the like having first discharge ports 64A and 114A and second discharge ports 64B and 114B, and are electrically driven hydraulically driven forward and reverse by electric motors 66 and 116. It is a pump, pumps up hydraulic oil from the reservoirs 62 and 112 by forward rotation of the electric motors 66 and 116, discharges hydraulic oil from the first discharge ports 64A and 114A, and from the reservoirs 62 and 112 by reverse rotation of the electric motors 66 and 116. The hydraulic oil is pumped up, and the pressure oil is discharged from the second discharge ports 64B and 114B.

  The hydraulic cylinder devices 70 and 120 have pistons 78 and 128 connected to piston rods 72 and 122 in cylinder tubes 76 and 126 so as to be slidable in the axial direction. And the second working chambers 82, 132 on the other side of the pistons 78, 128.

  The first discharge ports 64A and 114A are connected to the first working chambers 80 and 130 by oil passages 84 and 134, check valves 86 and 136, and oil passages 88 and 138, respectively. The second discharge ports 64B and 114B are connected to the second working chambers 82 and 132 by oil passages 90 and 140, check valves 92 and 142, and oil passages 94 and 144, respectively.

  The check valves 86 and 136 are check valves that allow only the flow of hydraulic oil toward the first working chambers 80 and 130 from the first discharge ports 64A and 114A. The check valves 92 and 142 are check valves that allow only the flow of hydraulic oil toward the second working chambers 82 and 132 from the second discharge ports 64B and 114B.

  Pressure regulating valves 96 and 146 are connected to the oil passages 84 and 134. The pressure adjusting valves 96 and 146 adjust the pressure of the hydraulic oil supplied to the first working chambers 80 and 130 to a constant value. Pressure regulating valves 98 and 148 are connected to the oil passages 90 and 140. The pressure adjusting valves 98 and 148 adjust the pressure of the hydraulic oil supplied to the second working chambers 82 and 132 to a constant value.

  The first relief valves 100 and 150 are connected to the oil passages 88 and 138. The first relief valves 100, 150 store the hydraulic oil in the first working chambers 80, 130 when the internal pressure (pressure of the hydraulic oil) in the first working chambers 80, 130 is equal to or higher than a first predetermined value. , 112.

  The second relief valves 102 and 152 are connected to the oil passages 94 and 144. The second relief valves 102 and 152 store the hydraulic oil in the second working chambers 82 and 132 when the internal pressure (pressure of the hydraulic oil) in the second working chambers 82 and 132 is equal to or higher than a second predetermined value. , 112. Note that the first predetermined value that is the relief pressure of the first relief valves 100 and 150 and the second predetermined value that is the relief pressure of the second relief valves 102 and 152 may be the same value, It is higher than the set pressure of the regulating valves 96, 146, 98, 148.

  The oil passages 84, 134, 88, 138, 90, 140, 94, 144, the check valves 86, 136, 92, 142, the pressure regulating valves 96, 146, 98, 148, and the first relief valve. 100 and 150 and the second relief valves 102 and 152 are modularized and incorporated in the valve cases 68 and 118.

  The electric motors 66 and 116 are controlled by a known solar tracking control device (not shown), and the rotation direction and the rotation angle are determined so that the solar panel 40 faces the sun.

  When adjusting the azimuth angle, when the electric motor 66 is driven in the forward rotation direction, the pressure oil from the first discharge port 64A of the hydraulic pump 64 passes through the oil passage 84, the check valve 86, and the oil passage 88, and the hydraulic cylinder. It is supplied to the first working chamber 80 of the device 70. When the pressure oil pressure acts on the piston 78, the internal pressure of the second working chamber 82 becomes higher than the relief pressure of the second relief valve 102, and the working oil in the second working chamber 82 becomes the second relief. While returning from the valve 102 to the reservoir 62, the piston rod 72 moves in a direction to increase the protrusion amount. As a result, the post member 18 rotates counterclockwise as viewed in FIG. 3, and the azimuth angle of the solar panel 40 is changed to the right when the solar panel 40 is viewed from the front.

  On the other hand, when the electric motor 66 is driven in the reverse rotation direction, the pressure oil passes through the oil passage 90, the check valve 92, and the oil passage 94 from the second discharge port 64 </ b> B of the hydraulic pump 64. Is supplied to the second working chamber 82. When the pressure oil acts on the piston 78, the internal pressure of the first working chamber 80 becomes higher than the relief pressure of the first relief valve 100, and the working oil in the first working chamber 80 becomes the first relief. While returning from the valve 100 to the reservoir 62, the piston rod 72 moves in a direction that reduces the amount of protrusion. As a result, the post member 18 rotates clockwise as viewed in FIG. 3, and the azimuth angle of the solar panel 40 is changed to the left when the solar panel 40 is viewed from the front.

  When adjusting the elevation angle, when the electric motor 116 is driven in the forward rotation direction, the hydraulic oil from the first discharge port 114 </ b> A of the hydraulic pump 114 passes through the oil passage 134, the check valve 136, and the oil passage 138. 120 first working chambers 130 are supplied. When the pressure oil pressure acts on the piston 128, the internal pressure of the second working chamber 132 becomes higher than the relief pressure of the second relief valve 152, and the working oil in the second working chamber 132 becomes the second relief. The piston rod 122 moves in a direction to increase the protruding amount while being returned from the valve 152 to the reservoir 112. As a result, the elevation angle adjusting shaft 24 rotates counterclockwise as viewed in FIG. 1 and is changed to the side (vertical side) where the elevation angle of the solar panel 40 increases.

  On the other hand, when the electric motor 116 is driven in the reverse rotation direction, the pressure oil from the second discharge port 114B of the hydraulic pump 114 passes through the oil passage 140, the check valve 142, and the oil passage 144, and the hydraulic cylinder device 120. The second working chamber 132 is supplied. When the pressure oil acts on the piston 128, the internal pressure of the first working chamber 130 becomes higher than the relief pressure of the first relief valve 150, and the working oil in the first working chamber 130 becomes the first relief. While returning from the valve 150 to the reservoir 112, the piston rod 122 moves in a direction that reduces the amount of protrusion. As a result, the elevation angle adjusting shaft 24 rotates in the clockwise direction as viewed in FIG. 1 and is changed to the side (horizontal side) where the elevation angle of the solar panel 40 decreases.

  The maximum adjustment angle θa of the elevation angle by the hydraulic linear drive device 110 is about 70 to 80 degrees as shown in FIGS. 1 and 5, but the maximum adjustment angle of the azimuth angle by the hydraulic linear drive device 60. θb is set to about 110 to 130 degrees as shown in FIGS. 3 and 4.

  The maximum adjustment angle θb of the azimuth is set so that the solar position is low and the solar power generation efficiency is low at times near sunrise or sunset, and the solar panel faces the sun at times near sunrise or sunset. Thus, even if the azimuth angle is not adjusted, the total amount of solar power generation per day is not greatly reduced. As a result, the adjustment of the azimuth angle can be performed by the hydraulic linear drive device 60 equivalent to the hydraulic linear drive device 110 that adjusts the elevation angle, the two-axis tracking drive system is simplified, and maintenance workability is improved. Is improved.

  In addition, since no gear-type reduction gear is used, there is no problem of backlash in both the azimuth angle adjustment and the elevation angle adjustment, and the solar panel 40 is moved in the azimuth and elevation directions by wind or the like. It does not rattle in any direction.

  Further, since the hydraulic linear drive devices 60 and 110 have the same structure, not only the maintenance workability is improved, but also the azimuth angle adjustment device and the elevation angle adjustment device are shared, and the maintenance parts are shared. As a result, the number of maintenance parts can be reduced. This is useful in a large-scale solar power plant in which a large number of solar panels are juxtaposed.

  The hydraulic linear drive devices 60 and 110 are configured such that the hydraulic cylinder devices 70 and 120 are moved backward by controlling the rotation direction of the electric motors 66 and 116, and no electromagnetic switching valve is used. Therefore, the structure is simple. As a result, maintenance-free performance is improved.

  The sun tracking control device does not continuously track the sun, but may perform intermittent tracking such as once every 10 minutes or once every 15 minutes. In this case, even if the operation of the electric motors 66 and 116 is stopped during the tracking interval, the hydraulic pressures in the first working chambers 80 and 130 of the hydraulic cylinder devices 70 and 120 are determined by the check valves 86 and 136 and the first relief. Sealed by the valves 100, 150, the hydraulic pressure in the second working chambers 82, 132 is sealed by the check valves 92, 142 and the second relief valves 102, 152, and the hydraulic cylinder devices 70, 120 are in the piston position. Since it is self-maintaining, power necessary for tracking can be saved. Further, it is not necessary to add a brake mechanism for holding the position of the solar panel 40, and the maintainability is improved.

  Although the present invention has been described above with reference to preferred embodiments thereof, the present invention is not limited to such embodiments and can be deviated from the spirit of the present invention, as will be readily understood by those skilled in the art. It is possible to change appropriately within the range not to be. For example, the adjustment of the azimuth angle and the adjustment of the elevation angle may be performed by a pneumatic linear drive device instead of the hydraulic linear drive devices 60 and 110. In addition, all the components shown in the above embodiment are not necessarily essential, and can be appropriately selected without departing from the gist of the present invention.

10 base 18 post member (first shaft member)
20 Elevation shaft support plate 22 Bearing bracket 24 Elevation angle adjustment shaft (second shaft member)
26 Panel support frame 32 Panel fixing member 34 Bearing sleeve 38 Light receiving surface 40 Solar panel 42 First mounting bracket 46 First swing arm 48 Ring member 49 Second mounting bracket 52 Second swing arm 60 Hydraulic linear Drive device (first fluid pressure linear drive device)
62 Reservoir 64 Hydraulic Pump 64A First Discharge Port 64B Second Discharge Port 66 Electric Motor 68 Valve Case 70 Hydraulic Cylinder Device 72 Piston Rod 76 Cylinder Tube 78 Piston 80 First Working Chamber 82 Second Working Chamber 86 Check Valve 92 check valve 96 pressure regulating valve 98 pressure regulating valve 100 first relief valve 102 second relief valve 110 hydraulic linear drive device (second fluid pressure linear drive device)
DESCRIPTION OF SYMBOLS 112 Reservoir 114 Hydraulic pump 114A 1st discharge port 114B 2nd discharge port 116 Electric motor 118 Valve case 120 Hydraulic cylinder apparatus 122 Piston rod 124 Connection piece part 126 Cylinder tube 128 Piston 130 1st working chamber 132 2nd working chamber 134 Oil path 136 Check valve 142 Check valve 146 Pressure adjustment valve 148 Pressure adjustment valve 150 First relief valve 152 Second relief valve

Claims (3)

A solar power generation device of a two-axis tracking system that performs solar tracking by adjusting an elevation angle and an azimuth angle of a solar panel having a light receiving surface of a solar cell on one side,
The base,
A first shaft member attached to the base and rotatable about a vertical axis;
A second shaft member attached to the first shaft member to support the solar panel and rotatable about a horizontal axis;
A first swing arm having one end fixed to the first shaft member;
A second swinging arm having one end fixed to the second shaft member;
A first hydrodynamic linear drive device having one end portion attached to the base and the other end connected to a first swing arm, and changing an azimuth angle of the solar panel;
Photovoltaic power generation having one end portion attached to the first shaft member, the other end portion connected to a second swing arm, and a second hydraulic linear drive device that changes the elevation angle of the solar panel. apparatus.   The photovoltaic power generation apparatus according to claim 1, wherein the first fluid pressure linear drive device and the second fluid pressure linear drive device have the same structure. The first hydraulic linear drive device and the second hydraulic linear drive device are:
A double-acting hydraulic cylinder device having a piston, having a first working chamber on one side of the piston, and having a second working chamber on the other side of the piston;
A reservoir for storing hydraulic oil;
A first discharge port and a second discharge port; hydraulic oil is supplied from the reservoir; pressure oil is discharged from the first discharge port by forward rotation of the electric motor; and second oil is discharged by reverse rotation of the electric motor. A bidirectional electric hydraulic pump that discharges pressure oil from the discharge port;
A first oil passage connecting the first discharge port and the first working chamber;
A second oil passage connecting the second discharge port and the second working chamber;
A first relief valve that is connected to the first working chamber and returns the working oil of the first working chamber to the reservoir when an internal pressure of the first working chamber is equal to or higher than a first predetermined value;
A second relief valve which is connected to the second working chamber and returns the working oil of the second working chamber to the reservoir when the internal pressure of the second working chamber is equal to or higher than a second predetermined value. The solar power generation device according to claim 2.

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