JPH07101400A - Solar battery paddle control device - Google Patents

Abstract

PURPOSE:To provide a solar battery paddle control device which is constituted to reduce the generation of a surplus power through regulation of inclination of a solar battery paddle based on the irradiation direction of solar light and simultaneously reduce deterioration of the solar battery through reduction of an irradiation amount of radiation, and reduce the size and the weight of the solar battery paddle. CONSTITUTION:A solar battery paddle control device comprises a solar battery 12 arranged to a solar battery paddle 11; a shunt dissipater 13 to consume a surplus content of a power generated by the solar battery 12: a power control device 16 to detect the surplus content of the power generated by the solar battery; and a paddle drive device 15 to regulate the direction of the solar battery paddle 11 so that the surplus content of a power detected by the power control device 16 is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar cell paddle control device mounted on an artificial satellite or the like.

[0002]

2. Description of the Related Art A conventional solar cell paddle controller will be described with reference to FIG.

Reference numeral 31 denotes a solar cell paddle, and the solar cell paddle 31 is provided with a solar cell 32 and a shunt dessicator 33 for consuming excess power generated by the solar cell. For example, the solar cell 32 is divided into an upper group 32a and a lower group 32b, and each group 32a, 3
Both 2b are connected to the shunt dessicator 33 via the diodes D1 and D2.

The electric power generated by the solar cell 32 is sent to the satellite body 34. The electric power sent from the solar cell 32 to the satellite body 34 is applied to the electric power control device 36 via the paddle drive device 35. Then, the electric power distribution device 37 distributes the electric power to a plurality of parts and supplies it to a load (not shown). The battery B is connected to the power control device 36, and when the satellite itself enters the shadow of the earth or the like and the solar cell 32 cannot generate power, the power supplied from the battery B is applied to the load.

A control signal is sent from the attitude control device 38 to the paddle drive device 35. And the solar cell 32
In order to generate the maximum electric power, the direction of the solar cell paddle 31 is controlled so that the surface of the solar cell 32 is perpendicular to the irradiation direction of sunlight, or as perpendicular as possible.

[0006]

The solar cell 32 arranged on the surface of the solar cell paddle 31 is composed of a semiconductor element of silicon or gallium arsenide. Therefore,
When the solar cell 32 is exposed to the radiation contained in the sunlight or the radiation supplemented to the Van Allen band of the earth in the space or the like, the crystal structure of the semiconductor element is destroyed and the solar cell 32
Power generation capacity will deteriorate.

Therefore, the power generation capacity of the solar cell 32 is designed by adding the power reduction due to deterioration to the power required for the satellite system in which the solar cell 32 is mounted. In this case, the size and gravity of the solar cell paddle 31 depends on the solar cell 3
It is almost determined by the generated power of 2. Therefore, as the amount of decrease in generated power due to irradiation of radiation increases, the size and weight of the solar cell paddle 31 increase.

By the way, the power generation capacity of the solar cell 32 is expected to decrease due to subsequent deterioration.
There is excess power in the early stages of the satellite launch.
If there is excess power, the bus voltage may exceed the specified upper limit value, and the power control device 36 monitors the bus voltage. Then, the shunt desicator signal S corresponding to the bus voltage is sent to the shunt dessicator 33, and the surplus power is consumed by the shunt dessicator 33 so that the bus voltage does not exceed the upper limit value.

When the solar cell 32 is made of, for example, silicon, the solar cell 3 is used when the artificial satellite is in a geostationary orbit.
The power generation capacity of 2 is about 2 in 10 years by irradiation of radiation.
Relatively deteriorates. Therefore, even if the power generation capacity of the solar cell 32 is reduced, in order to secure the necessary power, it is designed to generate about 1.25 times the load power immediately after the artificial satellite is launched. It

This pattern will be described with reference to FIG. The horizontal axis of FIG. 2 represents the period (year), and the vertical axis represents the generated power (W). 1
Assuming that the power required after 0 years is W1, the power generated immediately after the launch of the artificial satellite is W2 (about 1.25 times W1), and the power W2 decreases with the passage of the period (year).

Therefore, if the load is constant over the entire period, the shaded portion is consumed as excess power by the shunt dessicator. As described above, since it is necessary to anticipate a decrease in power generation capacity due to deterioration of the solar cell, the power generation capacity of the solar cell must be increased accordingly, and the size and weight of the solar cell paddle also increase. By the way, after the artificial satellite is launched, when the solar cell deteriorates with the passage of time, the surplus power gradually decreases and the bus voltage decreases. Therefore, the power controller 36 monitors the bus voltage and sends the shunt drive signal S corresponding to the bus voltage to the shunt desiccator 33. Then, the power consumed by the shunt dessicator 33 is reduced so that the bus voltage does not drop. It should be noted that the magnitude of the shunt drive signal S corresponds to the operating condition of the shunt dessicator 33, and also corresponds to the magnitude of the surplus power.

Further, in order to reduce the size and weight of the solar cell paddle, a method of suppressing deterioration of the solar cell due to radiation can be considered. For example, a method of covering the surface of the solar cell with a thick cover glass. However, if the cover glass is made thick, the weight of the solar cell paddle becomes heavy. Further, there is a problem that the amount of transmitted sunlight decreases and the generated power decreases.

As described above, in the conventional solar cell paddle control device, in order to make the best use of the power generation capacity of the solar cell, the solar cell surface is perpendicular to the irradiation direction of sunlight, and the surplus power is shunt-decided. It is configured to be consumed by peta. At this time, since the surface of the solar cell faces the irradiation direction of sunlight, the irradiation amount of the radiation from the sun also increases, and the deterioration is large accordingly. Therefore, it is necessary to expect a large amount of decrease in generated power due to deterioration of the solar cell over time, and the size and weight of the solar cell paddle are correspondingly large.

The present invention solves the above-mentioned drawbacks.
By adjusting the inclination of the solar array paddle with respect to the direction of sunlight irradiation, excess power can be reduced, and at the same time, the amount of radiation can be reduced to reduce deterioration of the solar cell and reduce the size and weight of the solar array paddle. An object is to provide a solar cell paddle control device.

[0015]

A solar cell paddle control device according to the present invention comprises a solar cell provided in the solar cell paddle,
A shunt dessicator that consumes the surplus of the electric power generated by the solar cell, a power control device that detects the surplus of the electric power generated by the solar cell, and the surplus of the power detected by the power control device. And a paddle drive device that adjusts the direction of the solar cell paddle so that the amount becomes smaller.

[0016]

According to the above construction, when there is surplus in the generated power of the solar cell immediately after launch, the direction of the solar cell paddle surface with respect to the irradiation direction of sunlight is shifted from the vertical direction to reduce the surplus power. At this time, the direction of the solar cell paddle surface deviates from the vertical direction, so that the solar radiation on the solar cell paddle surface of the solar cell also decreases. Therefore, it is possible to suppress the deterioration of the solar cell at a time when the surplus power is large such as immediately after the launch. For this reason,
Since the decrease in the power generation capacity due to the deterioration of the solar cell is small, the initial power generation capacity of the solar cell can be designed small. Therefore, the size and weight of the solar cell paddle can be reduced.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

Reference numeral 11 denotes a solar cell paddle. The solar cell paddle 11 is provided with a solar cell 12 and a shunt dessicator 13 for consuming excess power generated by the solar cell. The solar cell 12 is divided into an upper group 12a and a lower group 12b, and each of the groups 12a and 12b has a shunt desicator 1 through diodes D1 and D2.
Connected to 3.

The electric power generated by the solar cell 12 is sent to the satellite body 14. The electric power sent to the satellite body 14 is supplied to the electric power control device 16 via the paddle drive device 15. After that, the electric power distribution device 17 divides the electric power into a plurality of pieces and supplies them to a load (not shown). A battery B is connected to the power control device 16. When the satellite itself enters the shadow of the earth and the solar cell 12 cannot generate electric power, the electric power supplied from the battery B is applied to the load.

Further, the paddle drive device 15 is supplied with a control signal from the attitude control device 18, and controls the direction of the solar cell paddle with respect to the irradiation direction of sunlight. Further, the power control device 16 monitors the bus voltage and generates the shunt drive signal S corresponding to the magnitude of the bus voltage when the bus voltage rises and falls due to increase and decrease of surplus power. The shunt drive signal S is sent to the shunt dessicator 13 to adjust the surplus of the power consumed by the shunt dessicator 13.

The shunt drive signal S generated by the power controller 16 is also sent to the attitude controller 18.
The shunt drive signal S is a signal corresponding to the surplus of electric power, and the attitude control device 18 determines that the shunt drive signal S
The surplus of electric power is detected from the size of.

By the way, there are three operation modes for driving the solar cell paddle 11, that is, a clock mode, an automatic tracking mode, and a manual mode. For example, in the automatic tracking mode, the signal of the sun sensor is used to detect the sunlight. The direction of the solar cell paddle 11 is controlled so that the surface of the solar cell 12 is perpendicular to the irradiation direction.

However, when the surface of the solar cell 12 is vertically irradiated with sunlight, the power generation capacity of the solar cell 12 increases and the surplus of electric power increases. Therefore, the attitude control device 18 detects an increase / decrease in surplus power from the shunt drive signal S, and when the shunt drive signal S becomes equal to or greater than the specified value, the direction of the solar cell paddle 11 with respect to the irradiation direction of the sunlight is tilted more greatly. The power generated by the solar cell 12 is reduced to reduce the surplus power.

It should be noted that the solar cell 12
When the generated power decreases due to the deterioration of No. 1 and the surplus power decreases, the direction of the surface of the solar cell paddle 11 with respect to the irradiation direction of the sunlight is brought close to vertical, and the generated power of the solar cell 12 is increased.

As described above, when there is a surplus in the generated power of the solar cell, the surplus power is reduced by shifting the direction of the solar cell paddle surface with respect to the irradiation direction of sunlight from the vertical direction. At this time, by tilting the solar array paddle surface,
The amount of radiation emitted from the sun on the surface of the solar array paddle is reduced.

Therefore, when the surplus power is large such as immediately after the launch, the inclination of the solar cell paddle surface is large, the irradiation amount of the sun's radiation is small, and the deterioration of the solar cell is suppressed.

The relationship between the elapsed time after launch and the generated power will be described with reference to FIG. In FIG. 2, the horizontal axis represents the period (year) and the vertical axis represents the generated power (W). Assuming that the power required after 10 years is W1, it is expected that the solar cells will deteriorate in the conventional device, and the power generated immediately after the launch of the artificial satellite will be W2.
(About 1.25 times W1). However, in the case of the present embodiment, since the deterioration of the solar cell due to radiation is small, the power generated immediately after the artificial satellite is launched can be set to W0, which is smaller than W2, for example. Therefore, the power generation capacity of the solar cell can be designed to be small, and the size and weight of the solar cell paddle can be reduced.

[0028]

According to the present invention, it is possible to realize a solar cell paddle control device capable of reducing the generated power, size and weight of the solar cell paddle.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram showing an embodiment of the present invention.

FIG. 2 is a diagram illustrating an embodiment of the present invention.

FIG. 3 is a circuit configuration diagram showing a conventional example.

FIG. 4 is a diagram illustrating a conventional example.

[Explanation of symbols]

 11 ... Solar cell paddle 12 ... Solar cell 13 ... Shunt decipator 14 ... Satellite body 15 ... Paddle drive device 16 ... Power control device 17 ... Power distribution device 18 ... Attitude control device B ... Battery S ... Shunt drive signal

Claims (1)

[Claims] 1. A solar cell provided in a solar cell paddle, a shunt dessicator that consumes excess power generated by the solar cell, and power control that detects excess power generated by the solar cell. A solar cell paddle control device comprising: a device; and a paddle drive device that adjusts the direction of the solar cell paddle so that the surplus of the electric power detected by the power control device becomes small.