JPH0199443A - Sequential shunt apparatus - Google Patents

Abstract

PURPOSE:To relax sharp voltage change, by connecting superconducting coils in series respectively to switches. CONSTITUTION:To switches S1-Sn parallel-connected to solar batteries SA1-SAn in quantity n of a generating set 11, superconducting coils L1-Ln are connected in series. From the respective solar batteries SA1-SAn, power is fed to a load 12. When surplus power is generated and feed voltage is heightened, then output generated from a differential amplifier OP is increased, and by the working of a sequential shunt driving circuit SS14, the switches Sn, Sn-1,... are closed in order, and the input voltage of the load 12 is controlled to be constant. In this case, the solar battery SAn, the switch Sn, and the superconducting coil Ln form a closed loop, and power is stored in the superconducting coil Ln. For the coil Ln, superconducting material is used, and so there is no heat loss. Besides, at the transient time of closing the switch Sn, current change is relaxed.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) This invention provides a method for controlling surplus power generated by solar cells in electrical equipment that is operated while receiving power from solar cells. This invention relates to a sequential shunt device that stabilizes the power supply to electrical equipment.

(Prior art) In a power generation device configured with a solar cell that generates power slightly higher than the maximum power required by the load during sunshine, the output voltage is controlled in accordance with fluctuations in the power required by the load. is equipped with a sequential shunt device.

This sequential shunt device stabilizes the output voltage by installing a switch such as a non-contact switch between P and N of each solar cell, and opening and closing these as appropriate to suppress the surplus power generated by the solar cell. It was designed to make the

An example is shown in FIG. That is, the power generation device 11 has n
The solar battery cells SAI to SAn and the blocking diodes DAI to DAn for preventing backflow are connected in series, and each cell circuit is connected in parallel to each other.
The generated voltage is supplied to the load 12.

For such a power generation device 11, a sequential shunt device 13 connects switching elements (for example, transistors) Ql to Qn such as non-contact switches in parallel to each of the solar cells SAI to SAn.

Then, the output voltage (load supply voltage) of the power generation device 11 and the voltage of the Zener diode ZD corresponding to the set voltage are input to the differential amplifier OP, and the sequential shunt drive circuit SS is activated according to the amount of the difference voltage.

n switching elements Q are sequentially driven so that power can be supplied by a number of cells commensurate with the amount of load and the amount of generated power. Note that the capacitor C is for absorbing transient fluctuations in the output voltage when the switching element Q is opened and closed.

Figure 4 shows the output voltage-current characteristics of one solar cell SA when the amount of light is constant, and Figure 5 shows the output voltage-current characteristics of one solar cell SA when the amount of light changes. . That is, as is clear from FIGS. 4 and 5, the generated voltage of the solar cell SA fluctuates due to load fluctuations, and the generated voltage also fluctuates due to solar energy fluctuations.

The sequential shunt device detects a change in the generated voltage and short-circuits a number of cell circuits corresponding to the change, thereby stabilizing the load supply voltage.

However, in the conventional sequential shunt device as described above, the cell circuit is simply short-circuited step by step using a switching element, so the load supply voltage fluctuates greatly during transients, and in order to reduce the ripple caused by this fluctuation, a large capacitance Requires capacitor. Further, since the stepwise opening and closing is accompanied by steep voltage changes, EMI (electromagnetic induction interference) is likely to occur.

(Problems to be Solved by the Invention) As described above, the conventional sequential shunt device is a digital type that short-circuits multiple solar cell circuits step by step, so fluctuations in the load supply voltage during transient A large capacity capacitor is required to suppress E.
There was a drawback that MI was likely to occur.

In addition, there are some devices that control the generated voltage in an analog manner rather than stepwise by operating the transistor as a switch in an analog manner in a non-saturation region, but this has the disadvantage that the heat loss generated in the switching transistor is large. was there.

This invention was made to solve the above problems, and even when controlling the load supply voltage in stages, it is possible to alleviate the sudden voltage changes that occur at that time, and to reduce the EMI that occurs at this time. In addition, it is possible to store a portion of surplus power and temporarily supply it to a secondary storage battery for power supply in the shade. The purpose is to provide a shunt device.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the sequential shunt device according to the present invention provides A switch is placed between P and N of the battery cells, and the required number of cells are short-circuited through these switches to suppress the power generated by the solar cell to the required power and control surplus power. It is configured to include a plurality of superconducting coils each connected in series to the switch.

(Function) In the sequential shunt device with the above configuration, since the superconducting coil is connected in series with the switch, the superconducting coil becomes high impedance during the transition during opening and closing, and the solar cells are branched and the solar cells are short-circuited. It is possible to moderate the cell current change rate and suppress electromagnetic induction interference. Since a superconducting coil is used for the coil, the power generated by the short circuit current is stored in the superconducting coil, and when the switch is opened, this power can be stored in the secondary storage battery.Furthermore, by using the superconducting coil, heat loss can be reduced. can be reduced. - (Example) Hereinafter, the present invention will be explained in detail with reference to FIGS. 1 and 2.

FIG. 1 shows a configuration in which the present invention is applied to the sequential shunt device shown in FIG. 3. 1st
In the figure, the same parts as in FIG. 3 are designated by the same reference numerals.

In FIG. 1, n solar cells S of a power generation device 11
Superconducting coils 1 to Ln are connected in series to each of the switches 81 to Sn connected in parallel to AI to SAn, and further connected to the charging control circuit 141 via blocking diodes DBI to DBn.

This charging control circuit 141 includes each blocking diode D.
A charging current is supplied from the currents from BL to DBn to the secondary storage battery 143 according to the adjusted value by the charging amount adjustment circuit 142. The charging voltage of this secondary storage battery 143 is supplied to the load 12 via a blocking diode DC.

That is, each of the solar cells SAI to SAn supplies power to the load 12 via the 7' locking diodes DAI to DAn, but if surplus power is generated here and the supply voltage decreases, the difference in the sequential shunt device 14 The output of the dynamic amplifier OP increases, and the switches Sn, 5n-1, . As a result, the power generated by the solar cell power generation device 11 and the power consumption of the load 12 are balanced, and the input voltage of the load 12 is controlled to be constant.

On the other hand, if the switch Sn is closed due to an increase in the generated power,
An -3n-Ln becomes a closed loop, and the superconducting coil L
The power of 15c2/2 (where Isc is the inductance of Ln and Isc is the current flowing through Ln) is stored in n. At this time, since a superconducting material is used for the coil Ln, there is no heat loss. Also, during the transition period when the switch Sn closes, the superconducting coil Ln moderates the current change, so E
The occurrence of MI is also suppressed. In addition, when the generated power decreases or the load power consumption increases rapidly, the switch Sn is opened, the generated power of the solar cell SAn is input to the load 12, and the power stored in the superconducting coil Ln is transferred to the secondary battery by the charging control circuit 141. The storage battery 143 is charged.

Therefore, the sequential shunt device 1 having the above configuration
4, a superconducting coil and a switch are installed in series for each solar cell, so there is less EMI and no heat loss compared to conventional digital shunt devices. Further, since a part of the shunt power can be stored in the superconducting coil, it can be stored in the secondary storage battery 143 as part of the shade special power.

Figure 2 shows an example of application as a partial sequential shunt device, where the solar cells are 5A1n and 5A1n.
It is divided into two stages of cell A2n, and the above-mentioned shunt device is placed in the lower cell 5A2n.

In this case as well, the operation of the shunt device including the lower cell 5A2n is as described above, but at the moment when 5A2n is short-circuited by Sn, the change in the short-circuit current of 5A2n is slow, so the series terminal voltage of 5A1n and 5A2n is Change becomes slow. Therefore, the ripple in the load supply voltage is suppressed and
Power will be supplied at a more stable voltage.

[Effects of the Invention] As described above, according to the present invention, even when the load supply voltage is controlled in stages, it is possible to alleviate the sudden voltage change that occurs at that time, and to reduce the EM that occurs at this time.
In addition, it is possible to store a portion of the surplus power and temporarily supply it to a secondary storage battery for power supply in the shade, making it possible to operate it rationally as a power source. A sequential shunt device can be provided.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing one embodiment of a sequential shunt device according to the present invention, FIG. 2 is a circuit diagram showing another embodiment of the present invention, and FIG. 3 is a circuit diagram showing a conventional sequential shunt device. The circuit diagram showing the configuration, and FIGS. 4 and 5 are characteristic diagrams showing the output voltage-current characteristics of the solar battery cell, respectively. 11... Generator, 12... Load, 13.14...
・Sequential shunt device, Ll ~ Ln... superconducting coil, 31 ~ Sn = switch, DAI ~ DAn,
DBI~DBn, DC...blocking diode,
SS...Sequential shunt drive circuit, SAI~
SAn, 5All ~ 5Aln, 5A21 ~ 5A2n
・=Solar battery cell. Applicant's agent Patent attorney Takehiko Suzue

Claims (1)

[Claims] For solar cells formed by connecting multiple solar cells in parallel, a switch is placed between the electrodes of each solar cell, and the required number of cells are short-circuited through these switches. A sequential shunt device for controlling surplus power by suppressing generated power to a required power level, the sequential shunt device comprising a plurality of superconducting coils each connected in series to the switch.