RU2848580C1 - Photoelectric concentrator device - Google Patents

Abstract

FIELD: photoenergy.

SUBSTANCE: photovoltaic concentrator device includes a rectangular Fresnel lens panel designed to focus solar or laser radiation onto photovoltaic cells located on a heat-dissipating base, and support means for compact deployment of the device during launch and flight until deployment in orbit. The support means are in the form of four struts attached at one end to the corners of the rectangular Fresnel lens panel by means of cylindrical hinges with an opening angle of 180 degrees, and the other ends of the struts are attached to the corners of the base by means of cylindrical hinges with an opening angle of 90 degrees. Each strut is made of two rods of equal length connected to each other by cylindrical hinges with an opening angle of 180 degrees, spring-loaded by torsion cylindrical springs. The axes of all joints are parallel to the long sides of the base and the Fresnel lens panel, and the length of the short sides of the Fresnel lens panel and the base is set to be no less than the focal length of the Fresnel lenses.

EFFECT: ensuring compact folding of the device in the transport state and unfolding of the device when the spacecraft is deployed in orbit, while ensuring high efficiency of photoelectric conversion of laser and solar radiation.

1 cl, 4 dwg

Description

The invention relates to photovoltaics, specifically solar and laser photovoltaic systems designed to generate electricity on spacecraft. Photovoltaic conversion of concentrated solar and laser radiation is one of the most efficient methods for generating electrical energy from the Sun and laser radiation in space using highly efficient cascade solar cells, photovoltaic converters of laser radiation, and devices for orienting modules toward the Sun or a laser source.

A photovoltaic concentrator device is known (see US20110017875, IPC B64G 1/44, HOIL 31/042, published 27.01.2011), comprising a supporting structure of a spacecraft, on which photovoltaic concentrator modules are mounted, including a plurality of Fresnel reflectors directing light onto a panel of photovoltaic cells thermally connected to the central supporting structure via a heat pipe radiator. The heat pipe ensures the transfer of heat from the panel of photovoltaic cells and its dissipation on the heat pipe radiator and elements of the supporting structure.

The disadvantages of the known photovoltaic concentrator device are the low specific energy output due to the lack of a solar tracking system for the photovoltaic modules and the significant volume of the module when launched into space due to the lack of a system for folding the device during transport.

A photovoltaic device with a parabolic trough solar radiation concentrator is known (see RU2554674, IPC H01L 31/054, published 06/27/2015), comprising an asymmetric parabolic trough concentrator with a mirror-like internal reflective surface and a linear photovoltaic converter (PVC) located in the focal region with a uniform distribution of concentrated radiation along the axis. The linear PVC is equipped with a coolant flow system. The shape of the concentrator's reflective surface is determined by a system of equations corresponding to the condition of uniform illumination of the PVC surface, made in the form of a linear array of switched PVCs and located at an angle to the concentrator's midsection. The invention ensures operation of the photovoltaic device at high concentrations and uniform illumination of the PVC, obtaining a technically acceptable voltage on one PVC and increasing the conversion efficiency.

The disadvantages of the known photovoltaic device include the need to organize heat removal by circulating the coolant, as well as the low compactness of the device in the absence of a design for folding the module for its transportation into space, which leads to an increase in the mass and dimensions of the device when it is launched for installation on a spacecraft.

A photovoltaic concentrator device is known (see RU2740437, IPC H01L 31/02, published 14.01.2021), comprising a series of concentrator photovoltaic modules with rectangular or square housings with flanges for attaching Fresnel lens panels and solar cells, located at the foci of the Fresnel lenses, using silicone sealant. The photovoltaic concentrator modules are joined by overlapping flanges along the height in a staggered pattern. Moreover, in the outer row of concentrator photovoltaic modules and in rows of photovoltaic concentrator modules parallel to the outer row, the flanges of adjacent photovoltaic concentrator modules along the row are joined by an overlapping flange. In the rows of modules perpendicular to this outer row, the flanges of adjacent photovoltaic concentrator modules along the row are spaced from each other in height by a distance at least equal to the total thickness of the flange, silicone sealant, and Fresnel lens panel.

A disadvantage of the known photovoltaic concentrator device is the lack of compactness of the modules due to the lack of a design for folding the module during transport, which makes its transportation into space more difficult and expensive, which does not allow the use of a photovoltaic concentrator device on a spacecraft.

A foldable photovoltaic concentrator device is known (see RU193323, IPC H02S 10/40, H02S 30/20, F24H1/06, H02S 40/44, published 24.10.2019), comprising a parabolic trough concentrator, double-sided solar cells located in a photodetector, and a coolant. The concentrator is foldable, equipped with cylindrical hinges for folding and posts with openings for the solar cells. When folded, the device has the function of protecting the double-sided solar cells, and its profile ensures illumination of one or both receiving surfaces of the solar cell simultaneously. The solar cell housing is made of metal, has combined cavities for various functions, and provides cavities for the coolant with an inlet and outlet, with the ability to directly remove heat from the coolant. Bifacial solar cells have p-n junctions parallel to the flow of concentrated solar radiation. Thermal insulation of the coolant and the bifacial solar cells is provided on both sides. The coolant flows directly over the sealed bifacial solar cells, which are protected by transparent tempered glass.

A drawback of the known photovoltaic concentrator device is the insufficient rigidity of the concentrator structure. The presence of a joint between the folding elements of the concentrator leads to increased optical loss during solar radiation concentration. Furthermore, the chosen placement of the solar cell leads to a shift in the concentrator's focus relative to the solar cell, reducing the uniformity of solar cell illumination, and increasing solar radiation reflection.

A photovoltaic concentrator device is known (see US20140078607 IPC G02B 5/10, published 20.03.2014), comprising a base equipped with a rotating element, parabolic trough concentrators with a mirror-like internal reflective surface, mounted on the base, the cylindrical guides of which are parallel to the base and to each other, linear strings of solar cells mounted on the upper edge of the rear side of each subsequent concentrator in the focal line of each previous concentrator. Moreover, the cross-section of each parabolic trough concentrator, perpendicular to the cylindrical guides, is half a parabola. The rear surface of the first concentrator and the rear surface of the second concentrator face the rotating element, and the front surfaces of the first and second concentrators face in different directions, so that the center of equilibrium is located on the rotating element.

The disadvantages of the known photovoltaic concentrator device include its increased weight and dimensions due to the location of the rotating element on the light-receiving area. Furthermore, the lack of a folding design complicates and increases the cost of transporting the modules into space and installing them on a spacecraft.

A photovoltaic concentrator device is known (see patent US6111190, IPC H01L 31/045, IPC H01L 31/052, B64G 1/44, F24J 2/36, B64G 1/50, published 08/29/2000) based on an inflatable Fresnel lens. The device consists of a flexible Fresnel lens, flexible sides and a rear surface, which together cover the volume of a cavity that can be filled with a low-pressure gas for deploying the concentrator device in orbit. A solar energy photoconverter is located on the rear surface of the device, located in the focal region of the Fresnel lens. In addition, the rear surface can serve as a heat sink. Before deployment, the deflated flexible lens and sides are folded onto the rear surface to form a flat, low-volume package for efficient launch into space. A photovoltaic concentrator device using an inflatable lens allows for the reduction of the device's mass and volume before its launch into space.

A significant disadvantage of the known inflatable concentrator device is its low efficiency due to the low optical efficiency of the inflatable Fresnel lens.

A photoelectric concentrator device is known (see patent US6075200, IPC H01L 31/052, H01L 31/0232, B64G 1/22, F24J 2/08, B64G 1/44, published 13.06.2000), which coincides with the present technical solution in the greatest number of essential features and is adopted as a prototype. The photoelectric concentrator device includes a folding housing with folding end walls and with a device for deploying it, located in the folding housing, a panel of Fresnel lenses and a photogenerating panel parallel to it with solar cells located at the foci of the Fresnel lenses on the front surface of the rectangular base of the photogenerating panel, the back side of which is fixed to the solar orientation system. The Fresnel lens panel is flexible and attached to collapsible end walls. The end walls stretch the Fresnel lens panel to maintain its proper position and shape in space. The housing includes means for deploying the Fresnel lens panel in space. Before deployment, the flexible Fresnel lens panel and the housing end walls fold into a flat, compact package for launch into space.

The disadvantages of the known photoelectric concentrator prototype are low efficiency and insufficient rigidity of the folding structure, leading to defocusing of the Fresnel lenses.

The objective of this technical solution is to develop a photovoltaic concentrator device that would have a reduced volume in the folded transport state during flight and increased rigidity in the open working state in orbit.

The stated problem is solved in that the photoelectric concentrator device includes a rectangular panel of square Fresnel lenses, configured to focus solar or laser radiation into focal areas on photocells located in focal areas on a flat heat-dissipating base parallel to the plane of the Fresnel lens panel, made with a length and width equal to the dimensions of the projection of the rectangular Fresnel lens panel onto the flat base, deployable support means for installing the Fresnel lens panel in an appropriate position relative to the photocells, including mechanical means for compactly placing the photoelectric device during launch before deployment in orbit, characterized in that the deployable support means are made in the form of four racks attached at one end to the corners of the rectangular Fresnel lens panel by means of cylindrical hinges, and the other ends of the racks are attached to the corners of the base, coinciding with the projections of the corresponding corners of the Fresnel lens panel onto the base, by means of cylindrical hinges with an opening angle of 90 angular degrees between the racks and the short sides of the base and the lens panel Fresnel, where each stand is made of two rods of equal length, connected to each other by cylindrical hinges with an opening angle of 180 angular degrees, spring-loaded torsion cylindrical springs, while the axes of all the mentioned hinges are installed parallel to the long sides of the base and the panel of Fresnel lenses, and the length of the short sides of the panel of Fresnel lenses and the base is set to be no less than the focal length of the Fresnel lenses.

The technical result achieved by the given set of features is the provision of compact folding of the device in the transport state and the opening of the device during deployment of the spacecraft in orbit, while ensuring high efficiency of photoelectric conversion of laser and solar radiation, as well as stability of the characteristics of the device by ensuring the rigidity of the structure in the operating state.

The essence of the invention is explained by drawings, where:

Fig. 1 shows the design of the device in the open working condition during operation on a spacecraft: 1 - Fresnel lens panel; 2 - photocells; 3 - base; 4 - posts; 5 - corners of the Fresnel lens panel 1; 6 - cylindrical hinges; 7 - corners of the base 3; 8 - cylindrical hinges; 9-10 - rods that are integral parts of the posts 4; 11 - cylindrical spring-loaded hinges;

Fig. 2 shows the design of the device in an axonometric projection: 2 - photocells, 4 - stand, 8 - cylindrical hinges; 9-10 - rods, 11 - cylindrical hinges, 12 - Fresnel lenses;

Fig. 3 shows a view of the device from the side illuminated by a laser or the Sun: 13 - short sides of panel 1 of Fresnel lenses 12, 14 - long sides of panel 1 of Fresnel lenses 12, 15 - hinge axes;

Fig. 4 shows a view of the device in a folded state: 6, 8, - hinges, 9-10 - rods, 11 - cylindrical spring-loaded hinges connecting rods 9-10.

The photoelectric concentrator device includes a rectangular panel 1 (Fig. 1) of square Fresnel lenses 12, configured to focus solar or laser radiation into focal areas on photocells 2 located in the focal areas on a flat heat-dissipating base 3 parallel to the plane of the panel 1 of Fresnel lenses 12, configured with a length and width equal to the dimensions of the projection of the rectangular panel 1 of Fresnel lenses 12 onto the flat base 3. The device includes deployable support means for installing the panel 1 of Fresnel lenses 12 in the appropriate position relative to the photocells 2, including mechanical means for compact placement of the photoelectric device during launch before deployment in orbit. The deployable support means are made in the form of four posts 4 (Fig. 1), attached at one end to the corners 5 of the rectangular panel 1 of the Fresnel lenses 12 by means of cylindrical hinges 6 (Fig. 1), and the other ends of the posts 4 (Fig. 1) are attached to the corners 7 of the base 3, coinciding with the projections of the corresponding corners 5 of the panel 1 of the Fresnel lenses 12 onto the base 3, by means of cylindrical hinges 8 (Fig. 1), wherein the opening angle of the hinges 8 is set equal to 90 angular degrees between the posts 4 and the short sides 13 (Fig. 3) of the base 3 and the panel 1 of the Fresnel lenses 12, and each post 4 is made of two rods 9-10 of equal length (Fig. 1), connected to each other by cylindrical hinges 11 (Fig. 1) with an opening angle of 180 angular degrees, spring-loaded torsion cylindrical springs (not shown in the drawing), wherein the axes 15 of all the mentioned hinges 6, 8, and I are installed parallel to the long sides 14 of the base 3 and panel 1 of the Fresnel lenses 12, and the length of the short sides 13 of the panel 1 of the Fresnel lenses 12 and the base 3 is set to be no less than the focal length of the Fresnel lenses 12.

The implementation of deployable support means in the form of four posts 4 (Fig. 1), attached at one end to the corners 5 of the rectangular panel 1 of the Fresnel lenses 12 by means of cylindrical hinges 6, and at the other end of the posts 4 to the corners 7 of the base 3, coinciding with the projections of the corresponding corners 5 of the panel 1 of the Fresnel lenses 12 onto the base 3, by means of cylindrical hinges 8, ensures the possibility of compact folding of the device on Earth before its deployment in space orbit.

The implementation of the opening angle of hinges 6, 8 (Fig. 1) equal to 90 angular degrees ensures the fixation of the racks in the direction perpendicular to the plane of the panel 1 of the Fresnel lenses 12 and the base 3, which must be ensured in the deployed state of the device in space orbits.

The design of each stand 4 (Fig. 1) from two rods 9 and 10 of equal length, connected to each other by cylindrical hinges 11 with an opening angle of 180 angular degrees, spring-loaded torsion cylindrical springs (not shown in the drawing) ensures compact folding of the stands 4 in the transport state of the device (Fig. 4) and subsequent opening of the device in the working deployed state in orbit.

The 180° opening angle of the hinges 11 ensures that the position of the rods 9 and 10 is fixed in the position (Fig. 1, 2) perpendicular to the planes of the panel 1 of the Fresnel lenses 12 and the base 3, which is necessary to bring the device into a working condition in which the projections of the panel 1 of the Fresnel lenses 12 onto the base 3 coincide with the overall dimensions of the base 3.

The springing of the hinges 11 by torsion cylindrical springs is necessary for the automatic opening of the device into the working state in space orbit during the release (shooting off) of the protective shell of the spacecraft body, which protects the photoelectric device from the effects of unfavorable environmental conditions during the launch of the spacecraft into space orbit.

The axes 15 (Fig. 3) of all the mentioned hinges 6, 8, 11 are installed parallel to the long sides 14 of the base 3 and panel 1. This orientation of the axes 15 of the cylindrical hinges 6, 8, 11 ensures compact folding of the device (Fig. 4) on Earth in the transport state and subsequent automatic opening of the device into the working position (Fig. 1, 2) when deploying the device in space orbit.

The length of the short sides 13, panel 1 of the Fresnel lenses 12 and base 3 is set to be no less than the focal length of the Fresnel lenses 12. This condition must be met for compact folding of the device in the transport state. As can be seen from Fig. 4, the length of the short sides 13 of base 3 and panel 1 of the Fresnel lenses 12 must be no less than twice the length of rods 9-10, i.e. no less than the length of posts 4, which in turn must have a length equal to the focal length of the Fresnel lenses 12, which ensures the necessary coincidence of the focal areas with photocells 2. Thus, with the length of the short sides of panel 1 of the Fresnel lenses 12 and base 3 no less than the focal length of the Fresnel lenses 12, compact folding of the photoelectric device in the transport state and bringing the device into the working state when the device is deployed in space orbit are ensured.

The photovoltaic concentrator device operates as follows. In the folded transport state, the device is housed in a rectangular container with internal dimensions equal to the overall dimensions of the folded device shown in Fig. 4. The container is equipped with a removable lid, closely adjacent to the inner surface of the spacecraft skin, protecting the device from environmental influences during the launch of the spacecraft into orbit. During the deployment of the spacecraft in orbit, a portion of the spacecraft skin is removed along with the lid of the aforementioned container adjacent to the skin. As a result of these operations, the device opens under the action of four torsion springs built into cylindrical hinges and four struts 4 connecting the panel 1 of the Fresnel lenses 12 and the base 3. The device is activated by orienting the device toward the laser radiation source or the Sun using a laser radiation source position sensor or a Sun position sensor.

Example. A photoelectric concentrator device was constructed using a panel of six Fresnel lenses, each measuring 12 cm x 12 cm and having a focal length of 22 cm. The overall dimensions of the device are 22 cm x 24 cm x 36 cm when open (operating) and 1 cm x 24 cm x 36 cm when folded (for transport). As shown in Fig. 4, the thickness of the device when folded is equal to the sum of the diameters of the two hinges. In the developed device, the hinge diameter is 5 mm, and the thickness of the device is 1 cm. Thus, the developed device made it possible to reduce the volume of the container on the spacecraft by a factor of 22, which provides a significant economic effect, since the cost of delivering the device to orbit increases proportionally to the volume occupied by the device during transport.

Claims (1)

A photovoltaic concentrator device comprising a rectangular panel of square Fresnel lenses configured to focus solar or laser radiation into focal areas on photocells located in focal areas on a flat heat-dissipating base parallel to the plane of the Fresnel lens panel, configured with a length and width equal to the dimensions of the projection of the rectangular Fresnel lens panel onto the flat base, deployable support means for installing the Fresnel lens panel in an appropriate position relative to the photocells, including mechanical means for compactly placing the photovoltaic device during launch before deployment in orbit, characterized in that the deployable support means are made in the form of four posts attached at one end to the corners of the rectangular Fresnel lens panel by means of cylindrical hinges, and the other ends of the posts are attached to the corners of the base, coinciding with the projections of the corresponding corners of the Fresnel lens panel onto the base, by means of cylindrical hinges, wherein the opening angle of the hinges is set equal to 90 angular degrees between the posts and the short sides of the base and the lens panel Fresnel, where each stand is made of two rods of equal length, connected to each other by cylindrical hinges with an opening angle of 180 angular degrees, spring-loaded torsion cylindrical springs, while the axes of all the mentioned hinges are installed parallel to the long sides of the base and the panel of Fresnel lenses, and the length of the short sides of the panel of Fresnel lenses and the base is set to be no less than the focal length of the Fresnel lenses.