RU2645800C1 - Solar module with concentrator - Google Patents

Abstract

FIELD: solar engineering.

SUBSTANCE: invention relates to solar engineering, in particular, to solar modules with concentrators and photoelectrical and thermal detectors of solar irradiation. Solar module with the concentrator contains an annular semitoroidal mirror reflector and a radiation detector with a dual working area, installed in the center of symmetry of the module in flat surface of maximum cross-section, on which solar radiation with angle of entry of rays β_0. Diameter of the radiation detector is equal to the diameter of the cross section. On flat surface of maximum cross-section, free from receiver, a circular optical beam-deflection system, transparent to radiation, is established from n = 1, 2, 3…m, where n is a counting number, annular wedges with an acute angle ψ between the surface of entrance and exit of the rays, the plane of entrance face of the rays of the deflecting circular optical system are parallel to flat surface of maximum cross-section, and the angle of entry of the rays β₀, sharp corner ψ and the refracting index n of the material of deflecting optical system are connected with the angle of emergence of the rays β₄ by the relationship indicated in the formula of invention.

EFFECT: as a result of using the invention, it becomes possible to increase the use of solar radiation with a large angle of entry of the rays with a low position of the sun above the horizon.

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Description

The invention relates to the field of solar technology, in particular to solar modules with concentrators and photovoltaic and thermal receivers of solar radiation.

A solar module with a concentrator is known, containing a ring-shaped one-and-a-half mirror reflector and a radiation receiver with a two-sided working surface, mounted in the center of symmetry of the module in the midsection plane, onto which solar radiation is incident with a beam entry angle β ₀ , the diameter of the radiation receiver is equal to the diameter of the torus cross section (patent RF No. 2295675, IPC F24J 2/06, published March 20, 2007 Bull. No. 8). A sesquicidal hub is formed by cutting the toroid into two symmetrical surfaces with a plane passing through the centers of the cross section of the toroid. The cross-section of a half-toroidal reflector consists of two semicircles, which are the generators of the ring-shaped half-toroidal reflector. The radiation receiver front and rear working surface is installed in the plane of the midsection. The cross section of the reflector has a radius r and is removed from the center of symmetry of the reflector by a distance R, R = r. The center of symmetry of the receiver coincides with the center of symmetry of the reflector.

A disadvantage of the known solar module is the incomplete collection of solar radiation at the receiver at large angles of entry of the rays.

The proposed invention solves the following technical problem: it increases the optical efficiency of the solar module due to the concentration of radiation at the radiation receiver at large angles of incidence of the rays.

As a result of the application of the invention, it becomes possible to increase the use of solar radiation with a large angle of entry of rays at a low position of the Sun above the horizon.

The technical result is achieved by the fact that in a solar module with a concentrator containing a ring-shaped one and a half toroidal reflector and a radiation receiver with a two-sided working surface, mounted in the center of symmetry of the module in the midsection plane, onto which the solar radiation with a beam entry angle β ₀ falls, the diameter of the radiation receiver is according to the invention, a circular optical deflecting radiation transparent for radiation is mounted on the surface of the midsection plane free of the receiver according to the invention I am a system of n = 1, 2, 3 ... m, where n is a natural number, ring-shaped prisms with an acute angle ψ between the input and output surfaces of the rays, the plane of the input surface of the rays of the deflecting circular optical system are parallel to the midsection plane, and the angle of entry of the rays is β ₀ , the acute angle ψ and the refractive index n of the material of the deflecting optical system are related to the beam exit angle β _{4 by the} following relation:

In the design variant of the solar module with a concentrator, the acute angle ψ between the surfaces of the entrance and exit of the rays of the circular deflecting optical system is the same for all ring-shaped prisms.

In another embodiment of the design of a solar module with a concentrator, the acute angle ψ between the input and output surfaces of the rays of the circular deflecting optical system increases with the removal of ring-shaped prisms from the center of symmetry of the module with the formation of a Fresnel lens with a focal region.

The invention is illustrated by drawings, where

in FIG. 1 is a general view of a solar module with a concentrator;

in FIG. 2 is a cross section of a solar module with a concentrator in the meridional plane;

in FIG. 3 - the path of the rays in a circular optical deflecting system.

In FIG. 1, the solar module with a hub has a radiation receiver 1 of a round or square (shown by a dotted line) shape mounted on the axis of symmetry 2 of the module in the midsection plane 3, and a circular optical deflecting system 4 with a refractive index n based on the set of ring-shaped prisms 5 mounted on the working surface 6 (Fig. 2) of the module onto which the radiation is incident 7. The optical deflection system 4 is located between the outer boundary 8 of the diameter D of the solar module with the concentrator and the outer boundary 9 of the receiver 1 of diameter d.

In FIG. 2, a circular optical deflecting system 4 is made of two ring-shaped prisms 5 oriented from the outer boundary 8 to the center of symmetry 2 with an acute angle ψ between the entrance surface 10 and the beam exit surface 11. A circular optical deflecting system 4 and a one and a half toroidal reflector 12 of diameter D are mounted axisymmetrically with respect to the axis of symmetry 2. The diameter D of the one and a half toroidal reflector 12 and the diameter of the receiver 1 d are connected by the relation D = 2d. The receiver 1 is integrated axisymmetrically in the circular optical deflecting system 4 and has two working surfaces: the front 13, on which the solar radiation 7 falls, and the inner 14, on which the solar radiation arrives after reflection from the one and a half toroidal reflector 12.

In FIG. 3 shows the path of rays in a solar module with a concentrator, where β ₀ is the angle of entry of rays to the surface of the entrance 10 to the circular optical deflecting system 4, β ₁ is the angle between the refracted beam and the normal to the surface of the entrance of 10 rays within the circular optical deflecting system 4, β ₂ - the angle of the exit of the rays to the surface of the exit 11 inside the circular optical deflecting system 4, β ₃ - the angle of the exit of the rays on the surface of the exit 11 outside the circular optical deflecting system 4.

The angle β ₄ is the angle of entry of the rays at the input surface 15 of the one and a half toroidal reflector 12. The angles β ₀ , β ₁ , β ₂ , β ₃ , β ₄ are the angles between the directions of the rays and the normal to the corresponding surface. Since the surfaces of the entrance 10 and 15 of the rays are parallel, the angle β ₀ , responsible for cosine losses, is equal to the angle β _{4 of the} entrance to the sesquialoid mirror reflector 12.

The aperture angle α of the solar module with the concentrator is taken equal to α = ± 60 °, and one and a half of the mirror reflector 12 β _4max ± 90 °. For the positive direction of the angles α and β we take the angles of incidence of solar radiation 7, at which the angle between the beam 7 and the direction to the top of the prism with an acute angle ψ is less than 90 °, and negative if it is more than 90 °. The angle β ₀ = 0 corresponds to the normal incidence of solar radiation on the entrance surface of a circular optical deflecting system.

For the rays to the left of the radiation receiver in FIG. 2 and 3:

If β ₀ is given,

Then from formulas (1) - (4) the angle of entry of rays β ₀ , the acute angle ψ and the refractive index n of the material of the deflecting optical system are related to the angle of exit of rays β _{4 by the} following relation:

From formulas (5) - (8):

, солнечное излучение будет распространяться к приемнику 1 внутри круговой оптической отклоняющей системы 4.For angles β ₂ that are larger than the angle of total internal reflection

, solar radiation will propagate to the receiver 1 inside the circular optical deflection system 4.

Numerical calculation (1) - (4) for n = 1.5, ψ = 20 °, β_four= 50 °; β₃= 70 °; β₂= 40.49 °; β_one= 20.49 °; β₀= 31.47 °. According to formulas (5) - (8) for n = 1.5, ψ = 20 °, β₀= 30 °; β_one= 19.57 °; β₂= 39.57; β₃= 67.62 °: β_four= 47.62.

Formulas (1) - (8) are also valid for rays 7 to the right of receiver 1 in FIG. 2 and 3, but the angles of entry of the rays 7 β ₀ have negative values.

In the design variant of the solar module with a concentrator, the acute angle ψ between the surfaces of the input 10 and the output of the rays 11 of the circular deflecting optical system is not constant in magnitude for all ring-shaped prisms 5, but increases with the removal of the ring-shaped prisms 5 from the axis of symmetry 2 of the solar module with the concentrator, as this takes place in Fresnel lenses, in which refracted rays are collected in the focal region of the lens.

A solar module with a hub works as follows.

Solar radiation in the central zone of diameter d enters the front of the receiver 1, and solar radiation from the peripheral zone outside the receiver 1 after refraction in a circular optical deflecting system 4 is reflected from the surface of the sesqui-toroidal concentrator 12 and enters the inner surface of the receiver 1.

Geometric concentration coefficient of a solar module with a concentrator:

,

,

where D is the diameter of one and a half toroidal solar concentrator,

d is the diameter of the receiver.

With D = 312 mm, d = 156 mm, k = 4.

A silicon solar cell with a double-sided working surface, as well as a thermal solar collector for hot water supply and heating, can be used as a receiver.

The advantage of the proposed solar module compared to the prototype is its high optical efficiency due to the collection of a circular deflecting optical system of rays with a large angle of entry of the rays at a low position of the Sun above the horizon. The solar module within the aperture angle concentrates direct and scattered solar radiation.

Claims (5)

1. A solar module with a concentrator, containing a ring-shaped one and a half mirror reflector and a radiation receiver with a two-sided working surface, mounted in the center of symmetry of the module in the midsection plane, onto which the solar radiation is incident with a beam entry angle β ₀ , the diameter of the radiation receiver is equal to the diameter of the cross section, different the fact that on the surface of the midsection plane, free from the receiver, a circular optical deflecting system transparent for radiation is established from n = 1, 2, 3 ... m, where n is the natural number , Ring-shaped prisms with an acute angle ψ between the surface of the input and output rays entrance surface plane of rays deflecting circular optical system parallel to the plane of the midsection, and rays β entry angle _0, an acute angle ψ and the refractive index n of the material of the deflection optical system associated with an angle of output rays β _{4 by the} following relation:

,

. 2. A solar module with a concentrator according to claim 1, characterized in that the acute angle ψ between the input and output surfaces of the rays of the circular deflecting optical system is the same for all ring-shaped prisms. 3. A solar module with a concentrator according to claim 1, characterized in that the acute angle ψ between the input and output surfaces of the rays of the circular deflecting optical system increases with the removal of ring-shaped prisms from the center of symmetry of the module with the formation of a Fresnel lens with a focal region.

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