JPS59186378A - Collecting-type solar power generating device - Google Patents

Abstract

PURPOSE:To increase the output of a solar cell device and to simplify the structure of the driving system by a method wherein the tilt angle of a linear Fresnel lens to the horizontal plane, the incident angle of the solar ray, which passes through the central part of the lens, to the vertical line, and the like are set at the prescribed values according to the installed places of the lens. CONSTITUTION:A linear Fresnel lens 2 provided with a solar generating device is inclinedly fixed, facing to the south, and is trnsferred by a position controlling device with the transfer of the sun in the daytime in such a way that a solar cell element 1 keeps on coinciding with the focus part of the lens 2. The inclined fixing angle theta of this lens 2 to the horizontal plane is set at the value of phi-24 deg.<theta<phi+24 deg. to the latitude phi at the installed plate of the device and the element 1 is arranged so as to be able to transfer on the circumference of a radius equivalent to the focal distance of the lens 2, centering the center line 8 of the lens 2. Moreover, the relation between the incident angle alpha of the sunlight, which passes through the central part of the lens 2 in the southing time, to the vertical line and the angle beta, which is made by the straight line, which reaches to the element 1 from the center line 8 of the lens 2, with the solar ray, is set at alpha=beta=0, and the relation other than the one in the southing time is set as 0.9alpha<beta<13alpha for increasing the output of the device.

Description

[Detailed description of the invention] The present invention relates to the structure of a concentrating solar power generation device.

Concentrating solar power generation devices generally generate solar power by concentrating sunlight irradiated onto the ground using a lens or reflecting mirror, and placing, for example, a solar cell element at its focal point (or focal line). It is possible to significantly increase the power generation amount (per unit area of the solar cell element), and when compared with a non-concentrating solar power generation device, it requires fewer solar cell elements to obtain the same generated power. The advantage is that it can be done with In order to obtain a light concentrating system at a low cost, these concentrating solar power generation devices generally use Fresnel lenses made of transparent plastic materials, especially those with a low concentrating power of about 10 to 50 times. A linear Fresnel lens is used for the power generator. On the other hand, since concentrating solar power generation devices utilize only the direct sunlight that is irradiated onto the ground, they must track the sun as it changes time and position. The position of the sun changes due to temporal movement corresponding to the Earth's rotation and seasonal movement corresponding to the Earth's revolution. Therefore, in order to keep the concentrating solar power generation device directly facing the sunlight, it is necessary to prepare a tracking mechanism, for example, with two axes, which can track the sun according to the time and declination. However, the two-axis tracking mechanism has a complicated structure and a complicated tracking control method, so it has a high light concentration (for example, 100 times to 10 times more) that requires high tracking accuracy.
Although it is essential for a concentrating solar power generation device with a light concentration of about 0 times 0), it is not economical for a solar power generation device with a lower light concentration of υ. Therefore, conventionally, a method of tracking only the east-west axis, as shown in FIG. 1, in which the tracking mechanism is simplified, has been common. In FIG. 1, 1 is a solar cell element, 2 is a linear Fresnel lens, 3 is a movable frame for fixing the solar cell element and the linear Fresnel lens, and 5 and 6 are bearing parts for installing the movable frame at an angle. and 4 indicates the center of rotation of the movable frame. In the same figure, the movable frame is installed by a support to face due south as shown in the direction S, and the movable frame is angularly controlled using the rotation center. It can rotate in any direction and track sunlight.

On the other hand, the movable 7 frame for holding the linear 7 Renel lens and the solar cell element together must be designed to be strong considering the wind pressure, which increases the weight of the material used to support the movable frame. The pillars, including the bearings, will also become larger.
In order to stably track the sun over a long period of time, it is necessary to use strong members. The biggest reason for this is that the flat linear Fresnel lens, which is most susceptible to wind pressure, was mounted on the movable mechanism.

That is, in the conventional method, since the linear Fresnel lens and the solar cell element were mounted integrally on a movable frame, the movable frame and the pillars including the bearings for supporting the movable frame were damaged. Strong structural materials had to be used, and as a result, the structure of the bearing part and the structure of the drive system became larger, resulting in an unavoidable increase in material costs.Furthermore, the dimensions of the movable frame's constituent units also increased. The major drawback was that it was limited.

The present invention can eliminate such conventional drawbacks and provide a concentrating solar power generation device with a simple structure.

That is, according to the present invention, the linear (
A concentrating solar power generation device consisting of a linear) 7-Resnel lens and a solar cell element equipped with a position control mechanism so as to match the focal point of the 1-senior Fresnel lens that moves time-by-time with the movement of the sun during the day. , the fixed inclination angle θ between the linear Fresnel lens and the horizontal plane is ψ−24° with respect to the latitude ψ of the installation location of the concentrating solar power generation device.
ψ + 24°, and the position of the solar cell element is the center mfr: center of the linear 7-Resnel lens,
An incident angle α of sunlight with respect to a perpendicular line passing through the center of the linear Fresnel lens when the lens is moved on a circumference with a radius corresponding to the focal length of the linear Fresnel lens, and when the linear Fresnel lens is centered;
The angle β formed by the straight line from the center line of the linear Fresnel lens to the thick 1# battery element is α = β = 0 when the center line is in the south, and 09α〈β〈1,3α when it is outside the center line. A concentrating solar power generation device characterized by control can be obtained.

FIG. 2 shows a perspective view of an embodiment of the present invention.

In FIG. 2, 1 is a solar cell element, 2 is a linear Fresnel lens, 3 is a fixing frame for tilting and fixing the linear Fresnel lens, 7 is a paralysis 7' is a center line 80 of the linear Fresnel lens, both ends C2C' This is an arm that allows the solar cell element to move circumferentially around the center.

In the figure, the linear Fresnel lens is fixed by an ID fixing frame at an angle of inclination θ with respect to the horizontal plane, as indicated by 9 and S. On the other hand, the solar cell element 1 is located at the center point c+C of the linear 7-lens lens at arm 7.7'.
It is controlled so that it moves around the circumference in the a direction in the morning and in the p direction in the afternoon, centering on '. The focal line of the light incident obliquely on the linear Fresnel lens is generally fully concentrated near the optical axis passing through the center 8 of the linear Fresnel lens, and the focal line position changes depending on the position of the sun, which changes with time. also changes. The situation is shown in Figure 3.

In Figure 3, 1 is a solar cell element, ]' is a heat sink, and 2
indicates a linear Fresnel lens, and L indicates incident sunlight. Figure 3(a) shows sunlight incident on the linear Fresnel lens at right angles (i.e., incidence at the center of the sun), and Figure 3(f)
b) shows an example when sunlight is incident at an oblique angle.

In the same figure, the focal line is exactly located on the perpendicular line to the center of the linear 7 Renel lens at midday, but when sunlight is incident at an angle, the focal line is not necessarily the same as the light that has passed through the center of the linear 7 Renel lens. In other words, the angle α between the perpendicular to the linear Fresnel lens and the incident sunlight
The angle β formed by and the straight line from the center of the linear Fresnel lens to the solar cell element is not always equal. The reason for this is that oblique incidence of sunlight changes the focal line width and causes a bias in the intensity distribution of the focused light, and the bias depends on the incident angle α of the sunlight. However, it is not a constant value. However, by selecting the optimum value of the angle β within the range of 0.9α<β<1.3α with respect to the incident angle α, it is possible to place the solar cell element at the position of the peak value of the intensity distribution of the focused light. This makes it possible to obtain good solar cell output. On the other hand, the installation angle θ of the frame is ψ− relative to the latitude ψ of the installation location of the concentrating solar power generation device, in accordance with the declination.
It is unnecessary to explain that by taking a value of 24°<θ<ψ+24°, even better solar cell output can be obtained.

Furthermore, it is clear that the above explanation can be easily applied to a north-south single tracking type concentrating solar power generation device.

[Brief explanation of the drawing]

Fig. 1 is a perspective view schematically showing a conventional east-west single-axis tracking type concentrating solar power generation device, Fig. 2 is a perspective view showing an embodiment of the present invention, and Fig. 3 is a linear 7 Lennel lens. FIG. 2 is a schematic diagram showing the incident light angle and the state of condensation. In the figure, 1... solar cell element, 1'... heat sink, 2... linear 7 renel lens, 3... frame, 4... frame rotation center line, 5, 6 degrees. Support column including bearing part, 7... Arm, 8-...
Linear Fresnel lens center line. Agent Patent Attorney Susumu Uchihara [゛○ Matter 2 Figure

Claims (1)

[Claims] A concentrating solar power generation system equipped with a linear Fresnel lens fixedly tilted toward the south and a position control mechanism that moves the solar cell element as the sun moves during the day so that the solar cell element coincides with the focal line of the linear Fresnel lens. In the device, the fixed angle θ of inclination between the linear 7-Renel lens and the horizontal plane has a value of ψ −24° × θ + ψ + 24° with respect to the latitude ψ of the installation location of the concentrating solar power generation device, and the solar cell The element moves on a circumference centered on the center line of the linear Fresnel lens and has a radius corresponding to the focal line distance of the linear Fresnel lens, and when the element is placed in steel, sunlight is directed to a perpendicular line passing through the center of the linear Fresnel lens. The relationship between the incident angle α and the angle β formed by a straight line from the linear Fresnel lens center line to the solar cell element is α − β = 0 when it is raining, and Q when it is not raining, 9 α < β < 1 A concentrating solar power generation device characterized by .3α.