JPS63271978A - Solar battery array - Google Patents

Abstract

PURPOSE:To improve the efficiency of the operation by applying an insulation filler to conductive parts of solar battery cells or vacant areas or by filling the above parts or vacant areas with the insulation filler. CONSTITUTION:An insulation filler 6 is applied to conductive parts such as regions except for light receiving planes of solar battery cells 1, in other words, edge parts of the solar battery cells 1, electrodes 1a and 1b of the solar battery cells 1, surfaces of an interconnector 2, bus burs 7, terminal plates and the like as well as to vacant areas between the solar battery cells 1 and also the above conductive parts as well as the vacant areas are filled with the insulation filler 6. A coating material where resins, for example, those of silicon, epoxy, urethane systems and the like, each of which is stable in a space, are mixed with a white coating is used as the insulation filler 6. As a solar battery array is coated by this filler over a wide range, an operational temperature increase in the solar battery array is suppressed and its array can be operated efficiently.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a solar cell array, and is used as a power source in space equipment such as a space base or a satellite, or as a ground power source.

(Prior Art) In recent years, as satellites have become more sophisticated and multifunctional, the amount of electric power handled by these satellites has also tended to increase significantly. In particular, in space bases and solar power generation satellite systems that conduct experiments using the space environment, huge amounts of power are required, ranging from several hundred kW to several MW to several GW, rather than several hundred watts and several kilowatts like conventional satellites. is required. therefore,
When supplying such high power from the solar cell array to the necessary equipment, if the supply voltage is set to a lower voltage (<80 V) than conventional satellites, a very large four-body resistance loss will occur. It was necessary to make the supply voltage high.

(Problem to be solved by the invention) However, outer space is a vacuum, and in relatively low orbit, the power supply circuit must be kept at low voltage due to the interaction between the space plasma that exists and the solar cell circuit. However, conductor resistance loss due to this cannot be avoided, and
Although it is possible to eliminate conductor resistance loss by configuring a power supply path using superconductivity, the problem arises that the equipment required for this increases the weight.

By the way, the output power of silicon solar cells and gallium arsenic solar cells, which are most commonly used for the purpose of solar power generation, has a negative temperature coefficient. It has been found that more power can be obtained by lowering the operating temperature of constructed solar arrays. Here, the operating temperature of the solar cell array is determined by the heat balance between the heat input due to sunlight irradiation and the earth's albedo, and the energy radiated from the solar cell array to space, and the heat balance is as follows. In a highly efficient solar cell, α/ε≧1.

α: absorption rate of energy by sunlight ε: emissivity (balance is the same at α/ε-1) As a result, the temperature of this solar cell array tends to rise. Conventionally, the empty areas between each solar cell were coated with paint (thermal paint) in order to suppress the rise in the operating temperature of the solar array, but this method was not expected to have a sufficient effect, and There has been a desire to lower the operating temperature of battery arrays.

(Means for Solving the Problems) The solar cell array of the present invention is a solar cell array in which a plurality of solar cells are arranged on a substrate and these solar cells are electrically connected. An insulating filler is coated or filled in the conductive parts of the battery cells or in the empty areas between the solar cells.

(Operation) By coating or filling the conductive portion of the solar cell with an insulating filler, the conductive portion does not come into contact with the space plasma, and interaction with the space plasma is reduced or eliminated. Furthermore, by applying or filling the insulating filler on areas other than the light-receiving surface of the solar cell, the insulating filler covers a wide range of the solar cell array.

(Example) Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a plan view showing a part of the solar cell array of the present invention;
Figure 2 is an enlarged view of part A in Figure 1, and Figure 3 is an enlarged view of part A in Figure 1.
4 is a cross-sectional view taken along the line BB' in the figure, and FIG. 4 is a cross-sectional view taken along the line c-c' in FIG.

A front electrode 1a is formed on the light receiving surface of the solar cell 1, and a back electrode 1b is formed on the bottom surface of the solar cell 1. A plurality of solar cells 1 are electrically connected in series or in series and parallel by interconnectors 2 to produce a solar cell module 4, and this solar cell module 4 is bonded and placed on a substrate 3 with an adhesive 5. A solar cell array 10 is constructed. The reference numeral 7 in the figure is a bus bar for connecting the folded portion of the solar cell 1 in the solar cell module 4, and the reference numeral 8 is a cover glass attached to the light-receiving surface of the solar cell 1.

Furthermore, in this solar cell array 10, areas other than the light-receiving surface of the solar cell 1 (that is, the edge portion of the solar cell 1, the electrode 1a of the solar cell 1).

1b, the surface of the ink connector 2, the busper 7, conductive parts such as the terminal plate, and the empty area between the solar cells 1) are coated or filled with an insulating filler 6.

As the insulating filler 6, a mixture of a white paint and a silicone-based, epoxy-based, or urethane-based resin whose performance is stable in space is used. By mixing the insulating filler 6 with a white paint, it has a low absorption rate for solar irradiation light, and can suppress a rise in temperature due to solar irradiation light. The insulating filler 6 having such optical properties is applied to the conductive portion of the solar cell array by hand painting with a brush or by printing. At this time, the thickness of the applied insulating filler 6 is determined to minimize the increase in weight of the solar cell array.
It is preferable to make it as thin as possible.

Furthermore, the solar cell module 4 constituting this solar cell array can also be used on the ground. On the ground, interactions due to space plasma are not a problem, so
An insulating filler 6 is applied to improve weather resistance.

As the insulating filler 6 applied to the terrestrial solar cell module 4, a mixture of silicone-based, epoxy-based, urethane-based resin, or the like with black paint or white paint is used. Here, the cell temperature on the ground is not affected by thermal radiation like in space, and reflectance (1-α) and convection are important, so mixing black paint and white paint with the resin is used. They are used differently depending on the environment. That is, when used in a place where the annual average temperature is high, white paint is mixed. In addition, when the annual average temperature is low and the influence of snow blocking sunlight cannot be ignored, black paint is mixed in to increase absorption of solar heat and melt snow faster.

In this way, by selectively mixing the white paint and the black paint according to the environment in which they are used, and adjusting the optical properties of the insulating filler 6, that is, the absorption rate α for solar irradiation, Solar cells can be operated efficiently.

In addition, in terrestrial solar cell modules, insulating filler 6
Since the weight increase due to the coating is somewhat reduced, it is also possible to cover the entire solar cell l except for the light-receiving surface by filling it with this insulating filler 6.

(Effects of the Invention) As described above, according to the present invention, by coating or filling the conductive portion of the solar cell with an insulating filler,
Because interaction with space plasma is reduced or eliminated,
The supply voltage is expected to increase, making high-voltage power supply possible. In addition, in order to coat or fill an area other than the light-receiving surface of the solar cell with an insulating filler to cover a wide area of the solar cell array,
It is possible to suppress an increase in operating temperature in the solar cell array, and the solar cell array can be operated efficiently.

[Brief explanation of drawings]

FIG. 1 is a plan view showing a part of the solar cell array of the present invention;
Figure 2 is an enlarged view of part A in Figure 1, and Figure 3 is an enlarged view of part A in Figure 1.
FIG. 4 is a cross-sectional view taken along the line BB' in FIG. 2, and FIG. 4 is a cross-sectional view taken along the line c-c' in FIG. 1... Solar cell 4... Solar cell module 6... Insulating filler 10... Solar cell array 11
Figure 7 lI26! l! Lc′

Claims (1)

[Scope of Claims] 1) In a solar cell array formed by arranging a plurality of solar cells on a substrate and electrically connecting these solar cells, the conductive portion of the solar cell or the solar cell A solar cell array characterized in that an insulating filler is applied or filled in the empty area between.