JPS6037000B2 - Spacecraft power system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power supply system for a spacecraft that uses power from a solar cell array as an AC power source without using a switch circuit.

Conventionally, in a spacecraft whose power source is a solar cell array formed by electrically connecting multiple solar cells, the output from the solar cell array is set to a constant voltage or a DC voltage below a certain voltage using the configuration shown in Figure 1. It was used as a power source for the spacecraft. That is, in Fig. 1, la is a solar cell array, lb is a solar cell array (for control), 2a and 2b are backflow prevention diodes, 5 is a control circuit, 6 is a load circuit, and solar cell array la and solar cell array ( Control circuit 5 adjusts the output voltage to a constant value by using the non-linearity characteristic of solar cells in which the solar cell output voltage decreases as the load current of the solar cells increases. Or solar cell array (for control) lb so that it is below a certain value.
The current flowing through the load circuit 6 is increased or decreased to control the output voltage shown in FIG. 1 to a constant value or below a constant value, and the power generated by the solar cell is converted to DC power and used as a power source for the spacecraft. Therefore, although there are a large number of electronic devices that generally use AC power, if they are to be used in conventional spacecraft in the future, it will be necessary to add a device to convert DC to AC. Alternatively, the electronic devices that can be used are limited to those that use a DC power source. Furthermore, when a spacecraft such as an artificial satellite has a mission to measure magnetic fields in outer space, the current flowing through the power supply wiring generates a DC magnetic field, which disturbs the magnetic field near the spacecraft and affects the spacecraft's magnetic field measurements. Some conventional spacecraft have built-in devices that convert DC power to AC power. In such conventional systems, it is not possible to directly operate AC equipment with the power from the solar cell array as described above.

Furthermore, a device was required to convert direct current to alternating current. The purpose of this invention is to eliminate the above-mentioned drawbacks of the prior art and supply AC power to a spacecraft with a simple device.The feature of this invention is to electrically combine and connect multiple solar cells. A solar cell array consisting of the above is attached to the outer peripheral surface of the spacecraft so that the light-receiving surfaces of the two solar cell arrays, which are symmetrical about the rotational axis of the rotating spacecraft, face in opposite directions, and as the spacecraft rotates, the solar cell arrays are attached to the outer peripheral surface of the spacecraft. The above 2 facing each other in sequence
The output generated from the two large photovoltaic battery arrays is applied to the primary winding of the output transformer, and the directions of the output currents from the secondary windings of the output transformer are opposite to each other to obtain an AC power source. It's because I did it.

FIG. 2 is a conceptual diagram showing a configuration example of a spacecraft power supply according to the present invention when two solar cell arrays are used, la, lb
is a solar cell array, 2a and 2b are backflow prevention diodes,
3 is a transformer, 4 is a spacecraft body, and SP is a rotation axis of the rotating spacecraft body 4.

The solar cell arrays la, lb are two solar cell arrays la, lb that are symmetrical about the rotation axis SP of the spacecraft body 4.
The outputs generated from the two solar cell arrays la and lb, which are attached to the outer peripheral surface of the spacecraft body so that the light-receiving surfaces thereof face in opposite directions, and which face the sun sequentially as the spacecraft body 4 rotates, are transferred to the primary side of the transformer 3. The directions of the output currents applied to the windings and output from the primary winding of the transformer 3 are opposite to each other. In such a device, 2
Assuming that the outputs of the two solar cell arrays la and lb are the same,
In this case, due to the rotation of the spacecraft, the solar arrays la, l
Output currents as shown in FIG. 3a and b can be obtained from the output currents b. Therefore, these solar arrays la
, lb are connected to backflow prevention diodes 2a and 2b as shown in Figure 2.
is connected to the - secondary winding of the output transformer, and the electrical phases of the two primary windings from the solar cell arrays la and lb of the transformer with respect to the secondary winding are mutually opposite, that is, the secondary winding of the transformer 3. If the directions of the output currents from the windings are opposite to each other, a single-phase alternating current can be easily obtained as the output of the transformer 3. In this invention, a solar cell array consisting of a plurality of solar cells electrically connected together is arranged such that the light-receiving surfaces of the two solar cell arrays, which are symmetrical to the axis of rotation of a rotating spacecraft, are oriented in opposite directions. The two solar cell arrays are attached to the outer circumferential surface of the spacecraft so as to face the sun sequentially as the spacecraft rotates. Since the output of each solar cell array is combined by the transformer, an alternating current power source can be formed without the need for a special changeover switch circuit. , Therefore, the configuration of the power supply circuit can also be simplified.

Further, the total weight can be reduced, which is particularly preferable when weight reduction is required in a spacecraft such as an artificial satellite.

Furthermore, the present invention has the advantage that the magnetic field caused by the DC current loop is also extremely small. Brief explanation of drawings 1st
The figure is a power supply configuration diagram of a spacecraft using a conventional solar cell array, Figure 2 is a conceptual diagram showing an example of the equipment configuration for realizing the system according to the present invention, and Figure 3 is a diagram necessary for explaining the present invention. FIG. 2 is a diagram showing an example of a solar cell array output current.

In the figure, la and lb are solar cell arrays, 2a and 2b
is a backflow prevention diode, 3 is a transformer, and 4 is a spacecraft body.

Figure 3 Figure 1 Figure 2

Claims (1)

[Claims] 1. A solar cell array formed by electrically combining and connecting a plurality of solar cells is placed around the outer periphery of the spacecraft so that the light-receiving surfaces of the two solar cell arrays, which are symmetrical about the axis of rotation of the rotating spacecraft, are oriented in opposite directions. In the method of obtaining AC power from the output generated from the two solar cell arrays, which are mounted on a surface and face the sun sequentially as the spacecraft rotates, the output of each solar cell array is magnetically coupled to a secondary winding. is applied to two primary windings whose directions are opposite to each other, so that the output of each of the solar cell arrays is combined by a transformer consisting of the two primary windings and the secondary winding, A spacecraft power supply system characterized in that AC power is obtained from the secondary winding of the transformer.