JP2000340825A - Solar generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a solar generator which can be used as a self-illuminated advertisement, signpost, etc., by a method, wherein bypass diodes arranged in parallel with respective solar cells are replaced with light emitting diodes and a lighting circuit which applies currents to the light emitting diodes when there is no sunlight such as at a nighttime. SOLUTION: A solar cell group comprise a series circuit composed of a plurality of solar cells connected in series with each other, a 1st diode connected in series with the series circuit in the direction of taking out a current generated by the soar cells and 2nd diodes connected in parallel to the respective solar cells in directions giving reverse-bias voltages to the voltages generated by the respective solar cells. A solar generator comprises a plurality of the solar cell groups connected in parallel with each other. The 2nd diodes are replaced with light emitting diodes, and a diode lighting circuit 4 which applies currents to the light emitting diodes 2 is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photovoltaic power generation inverter device for supplying power to a load in connection with a commercial grid-connected power supply. The present invention relates to a photovoltaic power generation device in which a plurality of inverter devices supply electric power to the same single load by operating the photovoltaic power generation inverter devices in parallel.

[0002]

2. Description of the Related Art As disclosed in Japanese Patent Publication No. 7-44991, when a large number of solar cells are connected to secure output power, an input voltage required for a next-stage power converter is obtained. , Solar cells are connected in series, and the series circuits are connected in parallel as many as a required current can be obtained.
Here, when the series circuits of the solar cells are connected in parallel, a difference in the series total voltage generally occurs due to variations in solar radiation and variations in the characteristics of the solar cells themselves. To prevent current from flowing from the battery, insert a diode to prevent backflow and connect in parallel.

When a part of solar cells connected in series is blocked from solar radiation by a nearby building or fallen leaves, the output power of other solar cells in the same series part is interrupted. . In order to avoid the influence of shadows and fallen leaves of the neighboring buildings, a diode called a bypass diode is installed in a direction in which the power generation voltage of the solar cell is reversely biased. Through this diode,
The power generated by the solar cells other than the shaded portion in the same series portion can flow to the output side.

[0004]

However, the photovoltaic power generator having the above-described configuration performs power generation when there is daytime sunshine and plays a role as a device. However, since it has no function, there is a problem that the actual operation time of the device with respect to the service life is short.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to replace a bypass diode installed in parallel with each solar cell with a light emitting diode so as to provide an insolation at night or the like. In the case where there is no light emitting diode, by providing a lighting circuit for flowing a current to the light emitting diode, it is possible to provide an excellent solar power generation device that can be used as a self-illuminated advertisement or sign.

[0006]

According to the first aspect of the present invention,
A plurality of solar cells are connected in series, a first diode is further connected in series to the series circuit in a direction in which a generated current of the solar cells can be taken out, and a second diode is connected to the generated voltage of each solar cell. In a photovoltaic power generator in which a plurality of solar cells connected in parallel in a reverse bias direction are connected in parallel, a light emitting diode is provided instead of the second diode, and a light emitting diode lighting circuit for supplying a constant current to the light emitting diode is provided. It is characterized by having been provided.

The invention according to claim 2 is characterized in that a plurality of the light emitting diodes are connected in parallel.

The invention according to claim 3 is characterized in that a part of the second diode attached to the series-parallel solar cell is selectively replaced with the light emitting diode.

According to a fourth aspect of the present invention, a switch element is connected in parallel to the light emitting diode.

The invention according to claim 5 is characterized in that any one or all of the solar cell, the second diode, the light emitting diode, and the switch element are formed on the same semiconductor substrate.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention is shown in FIG. 1, a second embodiment is shown in FIG. 2, a third embodiment is shown in FIG. 3, and a fourth embodiment is shown in FIG. The fifth embodiment will be described in detail with reference to FIG.

[First Embodiment] As shown in FIG. 1, a solar cell 1, a light emitting diode 2, a diode 3, a light emitting diode lighting circuit 4, and a power converter 5 are provided. A plurality of solar cells 1 are connected in series, and a light emitting diode 2 is connected in parallel with each solar cell in a direction in which the generated voltage of the solar cell becomes reverse bias. The light emitting diodes 2 may be provided at a single ratio with respect to the plurality of solar cells 1.

A predetermined number of circuits in which the cathode of the diode 3 is connected to the negative electrode of the series circuit of the solar cell 1 are connected in parallel to obtain a required power generation. The power generated by the solar cell 1 is input to the power converter 5 via the diode 3, where it is converted into AC power and supplied to the grid. In addition, supply to a preset load is not limited to the system.

In addition to this configuration, the output of the light emitting diode lighting circuit 4 for obtaining a constant current output is connected to a series circuit of the light emitting diodes 2 to convert the system power supply 6 into a constant current necessary for lighting, and A current is supplied to the diode 2 to light it.

In this configuration, the power converter 5 and the LED
By controlling the lighting circuit 4, the power converter 5
Is driven to generate electric power from the solar cell 1 and LE is used at night.
The D lighting circuit 4 is driven to light the light emitting diodes on the panel.

[Second Embodiment] FIG. 2 shows a configuration in which a plurality of light emitting diodes 2 are connected in parallel in addition to the configuration of the first embodiment described above. With this configuration, the amount of light emitted by the light emitting diode 2 at night is increased.

The basic configuration of the photovoltaic power generator of this embodiment is very similar to that of the first embodiment, and the same parts are denoted by the same reference numerals and will not be described in detail. Omitted.

[Third Embodiment] FIG. 3 shows a configuration in which solar cells 1 are arranged in a panel shape in addition to the configuration of the above-described first embodiment. Here, as shown in FIG. 3 (a), a light emitting diode 2a is installed in parallel with the solar cell 1 in a portion 11 where characters and pictures are desired to be illuminated, as shown in FIG. 3 (b). FIG.
As shown in (b), the solar cell 1 has a configuration in which a normal diode 2b is provided.

[Fourth Embodiment] FIG. 4 shows, in addition to the configuration of the above-described first embodiment, a switching element 7 such as a transistor connected in parallel to a light emitting diode 2 connected in parallel to a solar cell 1. It has the following configuration. With this configuration, an arbitrary picture or character can be displayed on the solar cell / light emitting diode group arranged in a panel by selectively turning on / off the switch element 7.

[Fifth Embodiment] FIG. 5 shows that one unit of the solar cell 1, the light emitting diode 2, and the switch element 7 in the configuration of the fourth embodiment described above is one sheet. 1 shows a structure formed on a semiconductor substrate. Here, the region A constitutes the light emitting diode 2, the region A constitutes the switch element 7 (in this figure, an NPN bipolar transistor), and the region C constitutes the solar cell 1.

In the region A, a p-type semiconductor b is formed by impurity diffusion on an n-type semiconductor a serving as a base, and an n-type semiconductor c is formed so as to be joined to the p-type semiconductor b. b
And electrodes n and g are deposited on the n-type semiconductor c. In this configuration, when a current flows between the electrodes i and g, the light emitting diode emits light from the pn junction surface.

In the region A, a p-type semiconductor d is formed by impurity diffusion on an n-type semiconductor a serving as a base, and an n-type semiconductor e is further formed by impurity diffusion or the like to form an NPN bipolar transistor. An electrode i is formed as a collector electrode, an electrode h is formed as a base electrode, and an electrode g is formed as an emitter electrode.

In the region c, an n + layer having an impurity concentration required for solar cell characteristics is formed on the n-type semiconductor a by impurity diffusion, and a p-type semiconductor f is formed on the upper surface of the n + layer to form an electrode. Electric power is extracted from i and g to form a solar cell structure.

Note that an insulating layer j of silicon oxide or the like is formed in a portion where contact is prohibited when the common electrode portions of the regions A, A, and C are connected by vapor deposition.

[0025]

According to the first aspect of the present invention, when there is no sunshine at night or the like, a lighting circuit for flowing current to a light emitting diode installed in place of the bypass diode is provided, so that a self-illuminated advertisement or sign is provided. It can be used as a device, etc., eliminating the disadvantage that the actual operation time of the equipment is short with respect to the service life of the equipment itself, making it possible to use the equipment effectively, and in the case of a short-circuit failure of the solar cell, Since the emitting diode cannot be tented, it is possible to easily determine the location of the failure based on whether the LED is lit.

According to the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, since a plurality of light emitting diodes are installed in parallel, the amount of light can be increased, and the recognition and attention at night can be reduced. It has the effect of improving.

According to the third aspect of the present invention, in addition to the effect of the first aspect of the present invention, by selectively replacing a part of the bypass diode with a light emitting diode, the light emitting portion can directly draw a picture or image. This has the effect that characters can be expressed.

According to the fourth aspect of the present invention, in addition to the effects of the first to third aspects of the present invention, by controlling the switch element provided in parallel with the light emitting diode, a linear picture or character can be obtained. In addition to the above expression, there is an effect that these can be changed in time series.

According to the fifth aspect of the present invention, in addition to the effects of the first to fourth aspects of the present invention, further, by forming the circuit on the same semiconductor substrate, it is possible to reduce wiring labor and cost. This has the effect that it can be achieved.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a first embodiment of a photovoltaic power generator according to the present invention.

FIG. 2 is a circuit diagram showing a second embodiment of the photovoltaic power generator according to the present invention.

FIG. 3 is a configuration diagram showing a third embodiment of the photovoltaic power generator according to the present invention.

FIG. 4 is a circuit diagram showing a fourth embodiment of the photovoltaic power generator according to the present invention.

FIG. 5 is a semiconductor configuration sectional view showing a fifth embodiment of the photovoltaic power generator according to the present invention.

FIG. 6 is a circuit configuration diagram showing an embodiment of a conventional solar power generation device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Solar cell 2 Light emitting diode 3 Diode 4 Light emitting diode lighting circuit 5 Power converter 6 System power supply a, b, c, d, e, f Various semiconductors g, h, i Electrode j Oxide insulating layer

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hisami Usui 1048 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Works, Ltd. (72) Inventor Akira Yoshitake 1048 Kadoma Kadoma, Kadoma City, Osaka Matsushita Electric Works (72) Inventor Shinichiro Okamoto 1048 Kadoma, Kazuma, Osaka Prefecture Inside Matsushita Electric Works Co., Ltd. (72) Inventor Tadayoshi Mukai 1048 Odaka, Kazuma, Kadoma City, Osaka Prefecture F-term (reference) DA20 EA20 GA04 GA20 JA17 KA03 5G003 AA06 EA08 GB06

Claims (5)

[Claims] 1. A plurality of solar cells are connected in series, a first diode is further connected to this series circuit in a direction in which a generated current of the solar cells can be taken out, and a second diode is connected to each solar cell. In a photovoltaic power generator in which a plurality of solar cells connected in parallel in a reverse bias direction with respect to a generated voltage are provided with light emitting diodes instead of the second diodes, and a constant current is supplied to the light emitting diodes. A solar power generation device comprising a light emitting diode lighting circuit. 2. The photovoltaic power generator according to claim 1, wherein a plurality of said light emitting diodes are connected in parallel. 3. The photovoltaic power generator according to claim 1, wherein a part of a second diode attached to the solar cell configured in series and parallel is selectively replaced with the light emitting diode. 4. The photovoltaic power generator according to claim 2, wherein a switch element is connected in parallel to said light emitting diode. 5. The solar cell, a second diode,
5. The photovoltaic power generator according to claim 1, wherein at least one of the light emitting diode and the switch element is formed on the same semiconductor substrate.