阅读说明：本技术 十米直径的线性菲涅尔透镜系统 (Ten-meter diameter linear Fresnel lens system ) 是由 杨金玉 于 2018-08-01 设计创作，主要内容包括：十米直径的线性菲涅尔透镜系统,从高聚光太阳能发电系统整体考虑,逐一改变各组成,比如菲涅尔透镜的设计、直接利用大型平板玻璃生产线热压成型线性菲涅尔透镜、改变自动跟踪太阳的方式、抵抗恶劣环境的方法等,为高聚光太阳能利用闯低成本新路。(The linear Fresnel lens system with the diameter of ten meters is considered from the whole high-concentration solar power generation system, and the components are changed one by one, such as the design of a Fresnel lens, the hot-pressing molding of the linear Fresnel lens by directly utilizing a large-sized flat glass production line, the change of a solar automatic tracking mode, a method for resisting a severe environment and the like, so that a new way for utilizing high-concentration solar energy with low cost is provided.)

1. The utility model provides a linear fresnel lens system, includes fresnel lens's design, directly utilizes large-scale flat glass production line hot briquetting linear fresnel lens, changes the mode of automatic tracking sun, resists the method of adverse circumstances, its characterized in that:

a. the design of the Fresnel lens is divided into two steps:

after the glasses n and f are determined, the delta, f are calculated according to the fact that r is listed from small to large one by one,

TABLE 1

The data for each r point is then further processed with a sphere algorithm, see fig. 4:

s is a variable, for example, the increase is gradually carried out by taking 0.001mm as a basic unit; first, 0 to r in Table 1 are calculated₁Data of (1), this time equation

b. directly utilize large-scale plate glass production line, hot briquetting linear fresnel lens: the linear Fresnel lens with the diameter of 10 meters is directly hot-pressed by utilizing the existing plate glass production line and adding a carved roll shaft; the production of the engraved roll shaft, i.e. the production of the negative mold of the linear fresnel lens, is discussed first: the female die is 5 meters long as the pattern shown in figure 3, and can be machined by a horizontal numerical control lathe more than 5 meters; the data designed above can be used for machine tool processing only through the conversion of yin and yang; however, it should be noted that all arcs of all points in the above design are located on a horizontal line; the lathe machining needs to have the depth shown in figure 3, wherein x corresponds to s, but is not identical, x continuously rises from 0 to 0.5mm, then jumps to 0, and then repeatedly rises from 0 to 0.5 mm; the purpose of repeating the steps is to translate various curvature arcs of each point on the line into a complete and continuously-changed curve, namely the pattern of the figure 3; the roll shaft of 5 meters is just matched with a production line of 5 meters of plate glass, and two pieces of linear Fresnel lenses with the diameter of 10 meters can be manufactured by mirror image butt joint;

c. the method for changing the automatic sun tracking mode and resisting the severe environment comprises the following steps: in consideration of the requirements of resisting severe environment and reducing cost, a 10-meter linear Fresnel lens system is made into patterns of fig. 5 and 6; FIG. 5 is a diagram of an automatic tracking sunlight type, in which FIG. 1 is a 10 m × 10 m linear Fresnel lens; 2 is a solar cell on the focusing surface; the front wall 3 is fixed on the rotary chassis 7 and is connected with the linear Fresnel lens 1 in a hinge mode, and if the foundation can be dug deeply, the wall height can be reduced; the 4 is a rear wall, and a hydraulic and electric jacking bar 5 is arranged on the rear wall and used for supporting the linear Fresnel lens 1 to perform high-low opening and closing so as to play a role in precisely tracking the sun in the meridian direction; because the sun moves very slowly in the direction of the meridian, the change is imperceptible by day and changes greatly by seasons; the precise tracking of slow change is well processed, even manually operated; because the focusing surface of the linear Fresnel lens is laid in the horizontal direction, and the control direction is just opposite to the meridian, even in a cheap large-area linear Fresnel lens system figure 6, a hydraulic and electric jacking bar 5 is required; the rear wall is higher than the front wall, the linear Fresnel lens 1 is placed down and leans against the rear wall, and the linear Fresnel lens is provided with the front wall, the rear wall and connecting walls on two sides of the front wall and the rear wall to automatically form a protection ring for resisting severe environment; namely when encountering severe weather, the linear Fresnel lens 1 is selected to be put down immediately to lean against the rear wall 4; the rotating chassis 7 is circular, pulleys are arranged on the periphery of the rotating chassis, and can slide in a channel steel 6 which is connected with a foundation and bent into a circular ring shape, and the sliding rotation of the rotating chassis is controlled by a latitude direction sun controller to track the sun; the control precision requirement of the weft direction rotation controller is not high, and the controller is particularly firm and reliable.

Technical Field

The invention belongs to the technical field of Fresnel lenses.

Technical Field

Fresnel lenses have been widely used in the fields of optical projection, solar energy light-gathering power generation, and the like. At present, high concentration solar power generation has high cost and is not competitive with common flat-panel solar cells.

Disclosure of Invention

The purpose of the invention is as follows: considering the whole high-concentration solar power generation system, the design of Fresnel lenses, the hot-press molding of linear Fresnel lenses by directly utilizing a large-scale flat glass production line, the change of a solar automatic tracking mode, a method for resisting severe environment and the like are changed one by one, and a new way for utilizing high-concentration solar energy with low cost is provided. The following is described with reference to the accompanying drawings:

incident light is parallel light, but it is required that all the incident light after being refracted by glass (refractive index n) is concentrated on the same focal point F (see fig. 1), and the distance from the point a to the lens center O is OA ═ r, the focal length OF ═ F, and the included angle is set

Ab in the figure is the glass surface at point a,as the angle of incidence,

angle of refraction according to the law of optics

Can be derived from fig. 1

If the linear Fresnel lens is designed with equal spacing requirements, the result of FIG. 2 is that, for example, the spacing is 0.02mm, then

x represents depth, and although the difference points have different slopes, all are straight lines within the range of 0.02 mm. Replacing the original curve with a straight line will produce errors, especially in the edge portions further from the center.

We design the linear fresnel lens according to the equal depth type requirement (fig. 3, for example, 0.5mm depth), and each segment is processed according to the spherical curve, and the precision is naturally high. The curve of the central area is gentle, the curve of the edge area is steep, the total step number is much less than that of an equidistant type, and the processing and the manufacturing are also convenient. The radius of the spherical curve R ≠ f, which is determined according to the feature that all points on the spherical surface must be perpendicular to the sphere center: the length of the intersection of the perpendicular line of point A and the central axis of the lens in FIG. 1 is R, has

Where R is not constant and varies from one R to another. The specific design steps are divided into two steps: after determination of the glasses n and f

Firstly, calculating delta according to the list of r from small to large,

And (3) waiting for data:

TABLE 1

The data for each, point is then further processed with a sphere algorithm (fig. 4):

where s is a variable, such as increasing in steps with a base unit of 0.001 mm. First, 0 to r in Table 1 are calculated₁Data of (1), this time equation

Wherein R is R₁And (6) substituting. R gradually increases along with the gradual increase of s until r is more than or equal to r₂In the form of

Wherein R is replaced by R₂Substituting; then continuously increasing until r is more than or equal to r₃，Wherein R is replaced by R₃Substituting; then. This completes all calculations. We explain the calculation: when r is equal to r₁Increase to r₂R is used in the process₂Substitution, corresponding to the maintenance of half channel R₂A section of circular arc is drawn without change. The arc of the circle is 0 to r₁The arcs of (a) slightly differ in slope. But only 0 to r₁Is sufficiently small, the curve formed by the two arcs can be regarded as a continuous change.

The Fresnel lens with the diameter of 10 meters is manufactured by a method of directly hot-pressing and molding by utilizing the existing plate glass production line and adding a carved roll shaft. Firstly, the manufacturing of the engraved roll shaft, namely the manufacturing of a female die of the Fresnel lens: if the linear Fresnel lens scheme is adopted, the diameter of a roll shaft can be made to be as small as that of a roll shaft for ordinary embossing, a female die is 5 meters long as a pattern shown in figure 3 and can be machined by directly using a horizontal numerical control lathe with the length of more than 5 meters, and the polishing requirement can be slightly lower in consideration of the surface tension of hot glass. The designed data can be used for machine tool processing only through the yin-yang conversion. However, it is specifically noted that all arcs at all points in the above design are also on a horizontal line. The depth of the lathe is shown in FIG. 3, where x corresponds to s, but is not exactly the same, and x continuously rises from 0 to 0.5mm, then jumps to 0, and then repeatedly rises from 0 to 0.5 mm. The repeated aim is to translate the arcs of various curvatures of each point on the line into a complete and continuously-changed curve, such as the pattern shown in fig. 3. The roller shaft of 5 meters is just matched with a production line of 5 meters of plate glass, and two pieces of linear Fresnel lenses with the diameter of 10 meters can be manufactured by mirror image butt joint. Theoretically, if the width of a focusing spot of a 10-meter linear Fresnel lens is 1cm, the focusing spot is equivalent to 1000 suns. Thus, secondary focusing is not necessary because each time focusing is performed, the cost of the device is increased, and the loss of the light transmittance of 0.92 glass is increased. The energy per unit area of sunlight is changed by changing the setting of the upper and lower positions of the focal plane.

Drawings

FIG. 1 is a schematic diagram of the optical path of the present invention

FIG. 2 is a schematic view of an equidistant Fresnel lens according to the present invention

FIG. 3 is a schematic view of an equal depth Fresnel lens according to the present invention

FIG. 4 is a schematic diagram of the spherical surface calculation of the present invention

FIG. 5 is a view showing the structure of an automatic sunlight tracking type 10-meter linear Fresnel lens system according to the present invention

FIG. 6 is a view showing the configuration of an inexpensive large-area linear Fresnel lens system according to the present invention

Detailed Description

Considering the requirements of resisting severe environment and reducing cost, the linear Fresnel lens system with the length of 10 meters is made into the patterns of figures 5 and 6. FIG. 5 is a diagram of an automatic tracking sunlight type, in which FIG. 1 is a 10 m × 10 m linear Fresnel lens; 2 is a solar cell on the focusing surface; 3 is a front wall fixed on the rotating chassis 7 (if the foundation can be dug deeply, the wall height can be reduced), and is connected with the linear Fresnel lens 1 in a hinge mode; and 4, a rear wall is provided with a hydraulic and electric jacking bar 5 for supporting the linear Fresnel lens 1 to open and close in height, and the precise tracking function of the meridian direction on the sun is realized. Because the sun moves very slowly in the direction of the meridian, the change is imperceptible by day, and changes are large by season. The precise tracking of the slow change is easy to process, and even the manual operation is carried out. Because the focusing surface of the linear Fresnel lens is laid in the horizontal direction, and the control direction is just directed at the meridian, even though the civil heat supply cheap large-area linear Fresnel lens system is shown in a figure 6, a hydraulic and electric jacking bar 5 is required, so that the heat exchange tube in the horizontal direction can be ensured to track the sun all the time, and the position of the focal plane is lifted in the vertical direction, and meanwhile, the area of the heat exchange tube is increased. The rear wall is higher than the front wall, the linear Fresnel lens 1 is placed down to lean against the rear wall, and the linear Fresnel lens is provided with the front wall, the rear wall and connecting walls on two sides of the front wall and the rear wall to automatically form a protection ring for resisting severe environment. I.e. when subjected to inclement weather, the linear fresnel lens 1 is chosen to be set down immediately against the rear wall 4. The rotating chassis 7 is circular, pulleys are arranged on the periphery of the rotating chassis, and can slide in a channel steel 6 which is connected with a foundation and bent into a circular ring shape, and the sliding and the rotation of the rotating chassis are controlled by a latitude direction sun controller to track the sun; the control precision requirement of the weft direction rotation controller is not high, and the controller is particularly firm and reliable.