JPS60146310A - Solar battery power supply device - Google Patents

Abstract

PURPOSE:To prevent the generation of a shunt current by providing an array part for limiter to a solar battery array part and then unfolding and storing a part of the array part for limiter. CONSTITUTION:Plural solar battery elements 1 are connected in parallel and in series to form a solar battery array 10, and a limiter array part 1a and a main array part 1b are formed to each element 1. The electric power produced from the array 10 is supplied to a load 3 through a power control part 11 as well as to an accumulator 4. In this case, a reference power control signal is transmitted to a solar battery array control part 12 to drive a motor to unfold and store the array 10 when the part 11 detects an overcurrent, etc. in order to prevent the overstress to the load 3 and the battery 4. Then the part 12 decides the unfolding/storing width of the part 1a of the part 10 in response to said control signal and then unfolds and stores the part 1a through an array unfolding mechanism 7.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a solar cell power supply device used as a power supply device for a satellite, etc., and more specifically, to a solar cell power supply device that has improved control of surplus power generated in a solar cell array.

FIG. 1 shows an example of a conventional solar cell power supply device, which has a shunt circuit for consuming surplus power generated from a solar cell array.

In the figure, a plurality of solar cell elements 1 that convert light energy into electrical energy are connected in series and parallel to form a solar cell array 2. Energy generated by the solar cell array 2 is supplied to the load 3 through the power controller 5. The storage battery 4, which is connected in parallel to the load 3 through the power controller 5, is connected to the load when the load power becomes larger than the power generated by the solar cell array 2, or when the power generated by the solar cell array decreases. This is for supplying power to 3. The shunt circuit 6 consumes the surplus power generated by the solar cell array 2.

The power controller 5 receives the generated power from the solar cell 2,
The shunt circuit 6, the storage battery 4, and the load 3 are controlled to maintain a balance against surplus power and power shortage occurring between the power generated by the solar cell array and the load power.

That is, if the power generated by the solar cell array is insufficient, the storage battery 4 is controlled to supply the insufficient power to the load 3, and if there is surplus power, the necessary amount of power is charged to the storage battery 4. Control as follows. If power is still generated by the solar cell array after supplying power to the load 3 and charging the storage battery 4, the shunt circuit 6 is operated to consume the surplus power.

The solar cell array 2 is pulled out from the storage section 19 by the unfolding mechanism 7 and unfolded. The deployment mechanism 7 is driven by a drive motor and an extension boom driven by the motors, and the solar cell array 2 is deployed by the extension boom. The drive circuit section 8 is a circuit for controlling the drive motor.

As is clear from the above description, the conventional method for controlling the power generated by a solar battery power supply device is a method for dealing with the power that has already been generated.

In the above device, the current (power) generated by the solar cell array 2 is Isc, and the current consumed by the load is IL.

If the current charged to the storage battery is IBAT, Isc is (
When it becomes larger than IL + IBAT ), that is, when the relationship is Isc ) (IL + IBAT ), Isc - (IL + IBAT ) becomes surplus current = shunt magnetic current l5HNT9, and it must be completely consumed in the shunt circuit. That's it.

These relationships are shown in Figure 2 as voltage-current (V
- I) Explain in terms of characteristics. Curve 9 is the output of the solar cell array 2 shown in FIG. 1 obtained by applying the VI characteristic. VBL
18 is the operating voltage of this circuit, the intersection of Vaus and the VI characteristic 9 is set to E, and the E point is moved parallel to the voltage axis.
The point down to the current axis is A1. Similarly, point E is moved parallel to the current axis, and the point down to the voltage axis is H1. If the zero point is D, the area surrounded by A, D, H, and E is the solar cell array. The generated power at the operating voltage VBU8 of 2 is the generated current, and A is the generated current. Here, if the current consumed by load 3 is 0 and the charging current to the storage battery is B-0, then A-((B-0) +
O) = A - B is the surplus current k, that is, the shunt current A
, B, F, and B is the shunt power.

The shunt circuit 6 generally uses a power type resistor 6a. If this resistance value is R, then the shunt flow is
By flowing I 8 HPI T, I288NT
×Since the average power is consumed in the shunt circuit 6,
Most of it is converted into heat.

For example, when this device is mounted on a satellite, the generation of surplus current causes the heat generated from the shunt circuit to gradually accumulate inside the satellite, gradually increasing the temperature of the entire satellite, and causing the temperature of the entire satellite to rise. The temperature exceeds the allowable temperature of each device.ttn
It is also conceivable that it may cause malfunction or fatal failure.

In addition, even when thermal design of a satellite is performed by predicting the amount of heat generated from the shunt circuit, the amount of current generated by the solar array will vary depending on the load current amount depending on the satellite's operation mode and the amount of sunlight incident. This becomes extremely difficult because the amount of surplus current remains constant.

Moreover, when designing a shunt circuit, it is necessary to take into consideration the times when the load current and the charging current to the storage battery are zero, and have the ability to consume all the power generated by the solar array.

Moreover, there are few cases in which a redundant circuit is required in consideration of reliability.

These factors greatly restrict the mounting design of the satellite in that the external dimensions of the shunt circuit become larger.

As mentioned above, conventional devices of this type suffer from satellite malfunctions and failures due to heat generation in the shunt circuit, complicated thermal design, and mounting design constraints due to large external dimensions. There were some drawbacks such as:

An object of the present invention is to eliminate the above-mentioned drawbacks, and to provide a solar battery power supply device that generates only an amount of current equal to the amount of current required by the load and the storage battery, and does not generate surplus current, that is, shunt current. There is a particular thing.

In order to achieve the above object, the solar cell power supply device according to the present invention includes a solar cell array in which a plurality of solar cell elements are electrically connected in series and parallel, a storage section for storing the solar cell array, and a storage section for the solar cell array. a play expansion mechanism that controls the amount of electricity, a load, a storage battery, and when the generated power received from the solar cell array is larger than the consumption amount of the load, it is supplied to the storage battery, and when there is a surplus, a power supply corresponding to the surplus is provided. a solar cell array control section that compares the power control signal with a predetermined setting value and outputs a drive control signal that determines the drive amount of the array deployment mechanism; The structure is such that surplus power from the solar cell array can be generated as needed by storing or expanding a portion of the battery array.

According to the above configuration, the conventional problems can be solved and the object of the present invention can be completely achieved.

Hereinafter, the present invention will be explained in more detail with reference to the drawings.

FIG. 3 is a block diagram showing an embodiment of the solar cell power supply device according to the present invention.

In the figure, a solar cell array 1 includes a plurality of solar cell elements 1 that convert light energy into electrical energy connected in parallel and series.
0 is formed. Each solar cell element consists of a limiter array section 1a and a main array section 1b. The α force generated in the solar cell array 10 is supplied to the load 3 through the power control section 11. The storage pond 4 is connected to the solar cell array 10 through the power control section 11.The power control section 1
1 controls the output of the solar cell array 10, controls the charging/discharging flow rate to prevent excessive stress on the load 3, and prevents performance deterioration of the storage battery 4, and detects surplus current;
Solar ridge array control unit 12 Sends a power control signal that serves as a reference for driving the motor of the hair array deployment/storage boom. Thick 1
11! When the battery array control unit 12 receives the power control signal from the power control unit 11, it outputs a drive control signal that determines the expansion/storage@(amount) of the solar battery array IO in accordance with the power control signal. The array deployment mechanism 7 consists of an extension boom for deploying/storing the array and a drive motor for driving the boom.
The drive motor is driven by a drive control signal from the solar cell array controller 12.

Next, the operation will be explained.

First, if the output current Iso of the solar cell array 10 is larger than the sum of the current IL flowing through the load 3 and the charging current IBAT to the storage battery, then
+ IBAT means Iso, -(IL +IBAT)
surplus current is generated. Then, the power controller 11 detects the amount of surplus current and sends a power control signal such as Iso=IL+IBAT to the solar cell array controller 12. Upon receiving this signal, the solar cell array control unit 12 compares it with a preset value and determines whether the solar cell array 10
The paper is sent to the drive mechanism 7 using the storage width (amount) as a drive control signal, and a part of the array is stored. This reduces the light-receiving surface of the solar cell array 10, and as a result, Iso is limited to 15o=IL+IBAT.

The feature of this method is that all generated peepers are controlled by deploying or retracting a portion of the solar cell array.
This point will be explained below.

4 to 6 show embodiments of the solar cell array section of the solar cell power supply device according to the present invention, in which FIG. 4(a) shows a folding storage method, and FIG. FIG. 2 is an external view of a solar cell array.

5 and 6 show the array configuration of the solar cell array section, in which 13 is a limiter array section (a), middle to (b), and 14 is a main array section. FIG. 5 shows an example in which the array section is divided into four circuits. Each circuit is divided into a limiter array section (a) to 2) and a main array section, and the limiter array section is mounted at the base of the paddle as shown in FIG. Array part for limiter (a)
~(b) is connected in series with the main array, so
If the limiter array part is folded or otherwise prevented from being irradiated with sunlight, the solar cell element in this part will have the opposite characteristics of a diode, and even if the main array part connected in series with it is not irradiated with sunlight, the solar cell element in this part will have the opposite characteristics of a diode. No current flows. FIG. 7 is a diagram showing one equinodal circuit in the solar cell array. The same figure (al is the case where the limiter array part and the main array part are irradiated with sunlight, the same figure (bl is the case where only the main array part is irradiated with sunlight. In addition, 15 in the figure is the case where the limiter array part and the main array part are irradiated with sunlight. 16 is an isochoric circuit of the main array section.

Next, the operating principle of this device will be explained using the VI characteristic shown in FIG. Fig. 6 (VI when sunlight is irradiated to all of the limiter array parts (A) to (A) as shown in al) (
Curve 17 represents the voltage-current ratio. Next, when the limiter array section (c) is housed and sunlight is irradiated only on (a) and (b), the V-IW property becomes curve 18. Here, assuming that the configuration of the four-circuit array and the characteristics of the solar cell elements are all the same, the current value at VBus of curve 18 is approximately V2K higher than that of curve 17.

Next, when all the ε ivy array parts are stored, the current generated by the solar cell array becomes zero.

The above is an example of controlling the solar cell array generated current in four stages, but it is also possible to control it in multiple stages as necessary, and it can also be controlled continuously depending on the configuration of the limiter array section. .

As explained above in detail, the present invention provides a limiter array section in the solar cell array section, and by expanding/retracting a portion of the array, the current generated by the array can be controlled, so that surplus power is avoided unlike in conventional devices. This eliminates the need for a shunt circuit to consume energy, prevents temperature rise inside the satellite due to heat generated by the shunt circuit, and has the advantage of significantly reducing mounting space.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of a conventional solar cell power supply device, FIG. 2 is a graph showing voltage-current characteristics of a solar cell array, and FIG. 3 is a block diagram showing an example of a solar cell power supply device according to the present invention. , FIG. 4 is a perspective view showing the appearance of the solar cell array in FIG. 3, FIGS. 5 and 6 are configuration diagrams of the solar cell array according to the present invention, and FIG. 7 is a diagram showing one circuit in the solar cell array. The equivalent circuit diagram, FIG. 8, is an operational diagram of FIG. 3. l...Solar cell element 2...Solar cell array 3...
・Load 4...Storage battery 5...Power controller 6...Shunt circuit 7...Array expansion mechanism 8...Drive circuit 9...V-I% property
10... Solar cell array 11... Power control section 12... Solar cell array control section 13... Limiter array section 14... Main array section 15... Equal node circuit of limiter array section 16... Equinodal circuit of main array section 17. V-I characteristics Engineering s. 11-1% property 19... Storage section Patent applicant NEC Corporation Representative Patent attorney Hisashi Inoro Figure 5 6 Figure 27 (a) (shi) Age 8 Figure VBLIS -m- ■

Claims (1)

[Claims] A solar cell array in which a plurality of solar cell elements are electrically connected in series and parallel, a storage section that stores the solar cell array, a play expansion mechanism that controls the amount of input of the solar cell array, a load, a storage battery, and , a power control unit that supplies the power to the storage battery when the generated power received from the solar cell array is larger than the consumption amount of the load, and further generates a power control signal corresponding to the surplus when there is a surplus; A solar cell array control unit that compares the control signal with a predetermined setting value and outputs a drive control signal that determines the drive amount of the array deployment mechanism, and stores or deploys a part of the solar battery array. 1. A solar battery power supply device characterized in that the solar battery power supply device is configured to generate a surplus amount of power from a solar battery array.