JP2000197271A - Generation apparatus tied to power system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To operate properly fan in accordance with the driving of an inverter a ventilation for ventilating the inside of a housing for storing therein the inverter. SOLUTION: The power outputted from an inverter 14 is fed to a power supply 16 of a power system via contacts 64A, 64B of a parallel-off contactor 30 opened or closed through a microcomputer in an accompanied way by the driving of the inverter 14. Also, to a motor 62 of a ventilation fan 60 for ventilating the inside of a housing for storing therein the inverter 14, a power is fed via contacts 64B, 64C of the parallel-off contactor 30. As a result, the ventilation fan 60 is also operated/stopped according to the starting/stopping of the driving of the inverter 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system link which is provided in a photovoltaic power generator or the like for supplying power generated by using sunlight as an energy source to a system, and which operates in cooperation with the generated power and a system power supply. The present invention relates to a system power generator.

[0002]

2. Description of the Related Art In recent years, photovoltaic power generators have become widespread as grid-connected power generators that not only use electric power generated by sunlight for their own use but also regenerate surplus power not used for their own use to a system power supply line. I am doing it.

In a grid-connected power generator, DC power generated by a photovoltaic power generator is converted by an inverter circuit into AC power that matches the system power supply, and output to the line as system power.

[0004] When the inverter provided in such a grid-connected power generation device is housed in a tightly sealed enclosure strong body, it generates heat from a loss of conversion efficiency (usually 90% or more), and the temperature inside the enclosure increases. Therefore, in consideration of the reliability of the operation, a forced ventilation (cooling) device, for example, a ventilation fan is provided.

Further, another control device (for example, a timer or a solar radiation detecting device) for linking the ventilation fan with the operation of the inverter has been provided.

[0006]

However, in order to start power generation according to the amount of sunlight, the photovoltaic power generator operates the ventilation fan by extending the operation time to include the operation time of the inverter by using a timer or the like. You need to make it happen. For this reason, there is a problem that a time period during which the ventilation fan operates even though the inverter circuit is not operating occurs. Further, in order to detect the amount of solar radiation and operate the ventilation fan, it is necessary to always operate the solar radiation detecting device.

[0007] The present invention has been made in view of the above facts, and various types of cooling devices and pumps, such as cooling devices and pumps, which are operated only while a grid-connected power generation device such as a photovoltaic power generation device is operating as well as a ventilation fan. The purpose of the present invention is to propose a grid-connected power generation device that enables efficient use of electric power of equipment.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a power generation means and a power supply line of a system power supply after converting the power generated by the power generation means in accordance with the system power of the system power supply. An inverter to be output, and a power supply line provided between the inverter and the power supply line of the system power supply, which shuts off output of power from the inverter to the power supply line of the system power supply in response to a stop of the operation of the inverter. And a disconnection means for connecting the load to the load from the system power supply via the disconnection means so that power output from the inverter can be supplied to the load. Features.

According to the present invention, a predetermined load is connected to the inverter or the disconnection means, and when the inverter operates to start supplying power to the system power supply, power is supplied to the connected load. Like that.

Thus, the connected load can be operated when the inverter is operating, and the operation of the load can be stopped in accordance with the stop of the operation of the inverter.

[0011] As such a load, a ventilation fan for ventilating the inside of the housing accommodating the inverter can be connected. Thus, the ventilation fan can be properly operated only when the inverter is operating to generate heat, and ventilation in the housing can be performed.

Further, when the inverter is stopped, the ventilation fan is also stopped, so that the electric power for operating the ventilation fan can be used more efficiently than when a timer is used.

The present invention is not limited to the ventilation fan, and can connect various loads which are preferably operated in accordance with the operation of the inverter.

In the present invention, the load may be connected to operating means for controlling the operation of the disconnecting means.

Further, in the present invention, the power generation means may include a solar cell which generates electric power in accordance with the amount of sunlight received.

By operating the operating means in accordance with the operation of the inverter, for example, the load can be operated by the electric power supplied from the system power supply when the operation of the inverter is stopped.

Further, by using the solar power generation apparatus having a solar cell, the load can be operated in the daytime when the power is generated by the solar cell or at night when the power generation of the solar cell is stopped. Further, it is possible to connect a load in which only the operation time is limited such as a predetermined time or more within a day or within a predetermined time.

[0018]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of a grid-connected power generator according to the present invention.

FIG. 1 shows a schematic configuration of a photovoltaic power generator 10 to which the system interconnection device of the present invention is applied. The photovoltaic power generator 10 is connected to a solar cell 12 composed of a plurality of modules and a system interconnection device (hereinafter referred to as an “
4 ”), and the DC power generated by the solar cell 12 receiving sunlight is converted by the inverter 14 into AC power having a frequency corresponding to the system power supply 16.

The photovoltaic power generator 10 supplies the generated power to a distribution board 46 connected to the system power supply 16. The distribution board 46 is provided with a wiring breaker 48 serving as a main switch and a plurality of wiring breakers 50 serving as branch switches, and the power supplied from the system power supply 16 is supplied to the wiring breaker 48. ,
The power is supplied to the load 52 through the power supply 50.

The photovoltaic power generator 10 is connected to, for example, a distribution board 46 via a protective relay 54 and a circuit breaker 56.
Inside, it is connected to the line of the system power supply 16. In the photovoltaic power generator 10, the protection relay 54 can disconnect the power supply from the system power supply 16. This prevents abnormalities occurring in the system power supply 16 from spreading to the inverter 14. In addition, the solar power generation device 10
0V AC power is supplied to the line of the system power supply 16 of single-phase three-wire 100V / 200V.

As shown in FIG. 2, the inverter 14 of the photovoltaic power generator 10 includes a booster circuit 18, an inverter circuit 20, and a microcomputer 22 for controlling these. The DC current generated by the solar cell 12 is supplied to the booster circuit 18 via a diode 24 for preventing backflow, a circuit breaker (NFB) for protection, and a noise filter 26. FIG. 2 shows an example in which a plurality of solar cells 12 are connected in parallel.

The power output from the booster circuit 18 is supplied to the inverter circuit 20 and converted into AC power having substantially the same frequency as the system power supply 16. The AC power output from the inverter circuit 20 is supplied to the line of the system power supply 16 via the noise filter 28 and the parallel contactor 30.

On the other hand, the microcomputer 22 has a booster circuit 18 for boosting the DC power supplied from the solar cell 12 via the noise filter 26, and chops the DC power supplied from the booster circuit 18 based on the PWM theory. An inverter circuit 20 that outputs a pseudo sine wave having substantially the same frequency as the system power supply 16, a generated voltage detection unit 32 including an isolation amplifier that detects DC power input to the booster circuit 18, and a DC voltage input to the booster circuit 18. A generated current detection unit 34 including a current transformer (CT) for detecting current, a boosted voltage detection unit 36 including an isolation amplifier for detecting DC power output from the booster circuit 18, and an AC current output from the inverter circuit 20 Current transformer (CT) for detecting
And a voltage waveform detector 40 for detecting a system voltage and a voltage waveform of the system power supply 16 by a transformer (PT). In addition, the inverter circuit 2
At 0, a three-phase bridge is formed by the switching elements 42 connected in a bridge.

The microcomputer 22 includes a switching element (not shown) provided in the booster circuit 18 based on the generated power detected by the generated voltage detector 32 and the generated current detector 34 and the voltage detected by the voltage waveform detector 40. In addition to controlling the operation, the duty ratio of the switching signal for driving the switching element 42 of the inverter circuit 20 is controlled.

At this time, the microcomputer 22 operates the booster circuit 18 so as to output a DC voltage corresponding to the generated power and the system voltage.
And a switching signal is generated based on the voltage waveform of the system voltage detected by the voltage waveform detection unit 40 and output to the inverter circuit 20.

Thus, the microcomputer 22 outputs AC power whose phase and frequency match those of the system power supply 16 from the inverter circuit 20. Note that the on / off of the switching element 42 causes the inverter circuit 2
The AC power output from 0 has a sawtooth waveform, and the noise filter 28 removes harmonic components from the output power of the inverter circuit 20, so that the inverter 14 outputs sine-wave AC power.

On the other hand, the parallel contactor 30 is connected to the microcomputer 2
The microcomputer 22 connects and disconnects the photovoltaic power generator 10 and the system power supply 16 by the parallel contactor 30. For example,
The microcomputer 22 disconnects the photovoltaic power generator 10 from the system power supply 16 when the power generated by the solar cell 12 is low or does not generate power, and the operation of the inverter 14 is stopped. Immediately before starting, the photovoltaic power generator 10 and the system power supply 16 are connected.

The microcomputer 22 includes a voltage waveform detector 4
When it is determined from the voltage waveform detected by 0 that the system power supply 16 is in a power outage state, the solar power generation device 10 is quickly disconnected from the system power supply 16 by the disconnecting contactor 30,
The solar power generation device 10 (inverter 14) is prevented from operating alone. The configuration and control of the photovoltaic power generator 10 can be applied to a conventionally known configuration and control method, and a detailed description thereof will be omitted in the present embodiment.

By the way, as shown in FIGS. 1 and 2, the inverter 14 of the photovoltaic power generator 10 is housed in a housing 44. The housing 44 is attached to, for example, a wall surface of a building.

A ventilation fan 60 is attached to the housing 44. The ventilation fan 60 circulates air in the housing 44 and discharges the air in the housing 44 from an intake grill (not shown). The outside air is sucked and the air in the housing 44 is circulated.

As shown in FIG. 3, the ventilation fan 60 includes:
Electric power for driving the motor 62 is supplied via the parallel-off contactor 30.

The contact 64A, 6
A magnet switch having three contacts of 4B and 64C is used, and when the relay coil 66 is energized, the contacts 64A to 64C are closed. The microcomputer 22 operates the relay coil 66.

The power output from the noise filter 28 is supplied to the contacts 64A and 64C on the primary side of the disconnecting contactor 30. On the secondary side of the parallel contactor 30, the contacts 64A and 64C are connected to the system power supply 16, and the contact 64B is connected to the ground line. Thereby, the contact 6
100 between 4A and 64B and between contacts 64C and 64B.
V is applied.

On the other hand, the contact 64
The motor 62 of the ventilation fan 60 is connected to the primary side of B and 64C via the circuit breaker 68 for wiring. Thus, when the inverter 14 starts operating and outputs power to the system power supply 16, the contacts 64A to 64C of the parallel contactor 30 are closed to supply power to the motor of the ventilation fan 60, and the inverter 14 operates. Is stopped, the supply of power to the ventilation fan 60 is cut off. That is, in the solar power generation device 10, the ventilation fan 60 for ventilating the inside of the housing 44 in which the inverter 14 is accommodated is driven by the power generated by the solar cell 12 in accordance with the operation of the inverter 14. Has become.

The operation of the present embodiment will be described below.

When the solar cell 12 provided in the solar power generation device 10 receives sunlight, it generates electric power according to the amount of light. The solar power generation device 10 supplies power generated by the solar cell 12 to the inverter 14.

The microcomputer 22 provided in the inverter 14 monitors the power generated by the solar cell 12 by the generated voltage detector 32 and the generated current detector 34, and when the power exceeds a predetermined value, the operation of the inverter 14 is started. The boosted voltage output from the booster circuit 18 is set based on the system voltage detected by the voltage waveform detector 40 and the like.
The booster circuit 18 is operated so that the boosted voltage detected in 6 becomes the set voltage. Further, the microcomputer 22 turns on / off the switching element 42 provided in the inverter circuit 20 while controlling the duty ratio of the switching signal based on the voltage waveform detected by the voltage waveform detection unit 40. This allows the phase and frequency to be
Is output from the inverter circuit 20.

When the operation of the inverter 14 is started, the microcomputer 22 turns on the parallel-off contactor 30. As a result, the AC power output from the inverter circuit 20 passes through the noise filter 28, is supplied to the system power supply 16, and is supplied to the load 52 connected to the line of the system power supply 16 via the distribution board 46 by the sunlight. The power generated by the power generator 10 is supplied.

During the operation of the inverter 14, for example, heat may be generated from the switching element 42 or the like provided in the inverter circuit 20 and the temperature inside the housing 44 may rise. For this purpose, a ventilation fan 60 is provided in the housing 44 housing the inverter 14 to
While the vehicle is operating, the ventilation fan
The air whose temperature has risen along with the circulation of
It is discharged to the outside to suppress a rise in temperature inside the housing 44. As a result, the electrical components such as the switching element 42 housed in the housing 44 are not affected by the temperature rise.

On the other hand, in the photovoltaic power generator 10, a ventilation fan 60 for ventilating the housing 44 of the parallel-off contactor 30 is provided.
Is connected. As a result, when the inverter 14 starts operating and the parallel contactor 30 is turned on, the electric power generated by the solar cell 12 is supplied to the motor 62 of the ventilation fan 60, and ventilation in the housing 44 is performed. When the operation of the inverter 14 is stopped and the parallel contactor 30 is turned off, the energization of the motor 62 of the ventilation fan 60 is stopped.

As described above, in the photovoltaic power generator 10, since the ventilation fan 60 is turned on / off in accordance with the operation / stop of the inverter 14, a timer for operating the ventilation fan 60 in accordance with the operation of the inverter 14 is not required. Become.

Further, since the ventilation fan 60 is accurately turned on / off in accordance with the operation / stop of the inverter 14, the case 44 is operated in comparison with the case where the ventilation fan 60 is operated using a timer.
The use efficiency of electric power for ventilating the inside can be greatly improved. Is significantly improved.

That is, when a timer is used, there is a change in the sunshine duration, and the time must be set so that the ventilation fan 60 has a sufficient operating time. Further, when the amount of solar radiation is insufficient due to cloudiness or the like, the ventilation fan 60 may be operated even though the inverter 14 is not operating. On the other hand, in the photovoltaic power generator 10, the ventilation fan 60 operates according to the operation of the inverter 14.

The present embodiment described above does not limit the configuration of the present invention.

For example, in this embodiment, the inverter 1
Ventilation fan 60 for ventilating the inside of the housing 44 accommodating the housing 4
Can be operated in accordance with the operation of the inverter 14. However, since the solar power generation device 10 operates the daytime when the solar cell 12 is irradiated with sunlight,
A load to be operated only in the daytime may be connected to the circuit breaker 68 for wiring. Further, the load is not limited to the load operated in the daytime, but may be a load such as an air-conditioning ventilator that can be operated for a predetermined time or more in one day.

As described above, by connecting various loads to the parallel contactor 30 which is opened / closed in accordance with the operation / stop of the inverter 14, the power output from the inverter 14 can be reduced only while the inverter 14 is operating. Can be supplied.

Further, in the present embodiment, the electric power of 100 V is supplied to the ventilation fan 60 via the parallel contactor 30. However, since the photovoltaic power generator 10 generates the electric power of 200 V, the ventilation fan 60 is provided with a motor 62 for 200 V, and the electric power of 200 V
May be driven.

In this case, as shown in FIG. 4, the primary side of the circuit breaker 68 is connected to the contact 64 of the disconnecting contactor 30.
A, 64C.

Furthermore, in the present embodiment, the load such as the ventilation fan 60 connected to the parallel-off contactor 30 has been described as being operated by the electric power output from the inverter 14, but the output of the inverter 14 or the operation of the inverter 14 It is also possible to operate a contact or an opening / closing means such as a relay so as to open / close the contact when it is opened.

In this case, for example, by connecting the load 70 such as the ventilation fan 60 to the contact point 64B of the disconnecting contactor 30, the load 70 can be operated according to the operation of the inverter 14.

As shown in FIG. 6, a load 52 or a control means 72 for controlling the load 52 to which electric power is separately supplied from the distribution board 46 to the contact point 64B of the parallel contactor 30.
The load 52 can also be connected via.

Further, as shown in FIG. 7A, a relay coil 76 which is an operating means of a relay 74 which is an opening / closing means is connected to the contacts 64A and 64C of the disconnecting contactor 30, or FIG. As shown in FIG.
The relay coil 76 may be connected to the 4B or the contacts 64C and 64B.

Thus, the load 52 can be operated without using the power output from the inverter 14, as well as operating the load 52 in accordance with the operation / stop of the inverter 14. When stopped, the load 52 can be activated.
That is, the load 52 can be operated only when the operation of the inverter 14 is stopped.

Although the present embodiment has been described using the photovoltaic power generator 10 as the grid-connected power generator, the grid-connected power generator to which the present invention is applied is not limited to a photovoltaic power generator. The present invention can be applied to a grid-connected power generator having an arbitrary configuration for supplying generated power to the grid power supply 16, and power can be supplied to a load in accordance with operation / stop.

[0056]

As described above, according to the present invention, for example, a photovoltaic power generator is used as a grid-connected power generator, and a ventilation fan provided in a housing of the photovoltaic power generator is connected, so that the inverter can be used. The ventilation fan can be operated accurately according to the operation. In addition, by operating the ventilation fan accurately and efficiently, an excellent effect that the temperature rise in the housing when the inverter is operated can be suppressed can be obtained.

Similarly, even if a cooling device, an air-conditioning ventilation fan, a pump, various measuring instruments, and the like are used instead of the ventilation fan, the operation can be efficiently performed only when the solar power generation device is generating power.

[Brief description of the drawings]

FIG. 1 is a connection diagram schematically showing a connection between a photovoltaic power generator and a system power supply applied to the present embodiment.

FIG. 2 is a block diagram illustrating a schematic configuration of a solar power generation device.

FIG. 3 is a schematic connection diagram illustrating an example of connection of a ventilation fan to an inverter applied to the present embodiment.

FIG. 4 is a schematic connection diagram showing an example of connection to a ventilation fan operating at a voltage different from that in FIG. 3;

FIG. 5 is a schematic configuration diagram showing an example of connecting a load replaced with the ventilation fan shown in FIG. 3;

FIG. 6 is a schematic connection diagram showing an example in which a load or a load and a control means are connected to a contact of a parallel contactor as an application example of the present invention.

FIGS. 7A and 7B are schematic connection diagrams showing an example using a relay coil as an application example of the present invention; FIG.
Shows an example of operating at 200V, and (B) shows an example of operating at 100V.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Photovoltaic power generation apparatus (system interconnection power generation apparatus) 12 Solar cell 14 Inverter 16 System power supply 22 Microcomputer 30 Disconnection contactor (disconnection means) 44 Housing 52, 70 load, 60 ventilation fan (load) 62 Motor (load) 72 Control means 74 Relay (opening / closing means) 76 Relay coil (operating means)

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masaki Banri 2-5-2-5, Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Isao Morita 2-chome Keihanhondori, Moriguchi-shi, Osaka No. 5-5 Sanyo Electric Co., Ltd. (72) Inventor Toshio Ueda 2-5-5 Keihan Hondori, Moriguchi City, Osaka Pref. Inside Sanyo Electric Co., Ltd. (72) Inventor Kuniho Tanaka Dainichi, Moriguchi City, Osaka No. 1 Higashicho Sanyo Solar Engineering Co., Ltd. F-term (reference) 5F051 KA01 KA03 5G066 HA06 HB06 LA01 5H007 BB07 CA01 CB05 CC09 CC12 DB01 DB12 DC02 DC05 GA09 HA06 5H420 BB14 CC03 CC06 CC10 DD03 DD10 EA10 EA37 EB04 EB04 EB04 EB04 EB04 EB39 FF04 FF22 FF25

Claims (4)

[Claims] A power generation unit, an inverter that converts power generated by the power generation unit in accordance with system power of a system power supply, and outputs the converted power to a power line of the system power supply; A disconnection means provided between the power supply line and a power supply line of a system power supply corresponding to a time when the operation of the inverter is stopped. And a load connected to the load via the disconnecting means from the system power supply, so that power output from the inverter can be supplied to the load. 2. An operation means for controlling an operation of said disconnection means as said load is connected.
The grid-connected power generator according to item 1. 3. The grid-connected power generation device according to claim 1, wherein the power generation unit includes a solar cell that generates power according to an amount of received sunlight. 4. The air conditioner according to claim 1, further comprising: a housing accommodating said inverter; and a ventilation fan provided in said housing to ventilate said housing, said ventilation fan being connected as said load. Alternatively, the grid-connected power generator according to claim 3.