JP2000092718A - Distributed power supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the power consumption of a whole system substantially by a method wherein, among respective power generating units, the units which are not generating power are stopped to eliminate the power consumption of the units. SOLUTION: Respective power generating units 2a-2n are operated by power obtained by the respective solar cell panels 11 of the power generating units 2a-2n. AC voltages outputted from the respective power generating units 2a-2n are introduced to a linkage control board 5 through a power line 3 while the respective power generating units 2a-2n are monitored by a monitoring device 6, and the AC voltages and an AC voltage supplied by a commercial power supply 4 are linked with each other and supplied to a load.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distributed power supply system in which power generation units are dispersedly arranged, such as a photovoltaic power generation system and a wind power generation system, and in particular, utilizes electric power obtained by each power generation unit. The present invention relates to a distributed power supply system that operates each power generation unit to monitor each other.

[0002]

2. Description of the Related Art In a distributed power supply system in which power generation units are dispersedly arranged, such as a solar power generation system or a wind power generation system, a DC voltage generated by each power generation unit is converted by a power conditioner device such as an inverter device. The voltage is converted into an AC voltage and supplied to a load.

However, in such a distributed power supply system, for example, a photovoltaic power generation system, each DC voltage output from each power generation unit is combined into one on a DC bus, and then one inverter device is used. And convert it to AC voltage, so the DC wiring work from each power generation unit to the inverter unit is not only a huge amount of work, but also the amount of power generated by each power generation unit when designing each power generation unit. Have to be made almost the same, and there has been a problem that the system design is complicated by that much.

Therefore, as a method of solving such a problem, an inverter device is provided for each power generation unit, and each inverter device converts a DC voltage output from a solar cell panel of each power generation unit into an AC voltage. Accordingly, a method has been developed in which the power generation amount of each power generation unit can be arbitrarily set and the amount of DC wiring work is reduced.

FIG. 5 is a block diagram showing an example of a photovoltaic power generation system using such a method.

The solar power generation system 101 shown in FIG.
Are a plurality of power generation units 102a to 102n that take in sunlight and generate an AC voltage;
a to 102n are combined into one power line 103, and the one AC voltage combined by the power line 103 and the AC voltage supplied from the commercial power supply 104 are linked to each other and supplied to the load. Linked control panel 105
And each power generation unit 102
a monitoring device 106 for monitoring the operation status of the a to 102n;
The monitoring device 106 and each of the power generation units 102a to 102
n and the link control panel 10
A part of the AC voltage output from the
2 a to 102 n and a system power supply line 108 to be supplied to the monitoring device 106.

In this photovoltaic power generation system 101, a part of the AC voltage output from the coordination control panel 105 is transmitted to each of the power generation units 102 a to 102 by the system power supply line 108.
n and the monitoring device 106, and while operating these, the monitoring device 106
102 n are monitored. Then, by the power line 103, the respective AC voltages output from the respective power generation units 102a to 102n are put together and led to the coordination control panel 105,
The AC voltage and the AC voltage supplied from the commercial power supply 104 are linked and supplied to the load.

At this time, each of the power generation units 102a to 102
n, the network 1 is monitored by each monitoring station 109 provided for each of the power generation units 102a to 102n.
07, the respective inverter devices 110 are operated according to the power generation schedule obtained by this communication operation, and the DC voltage output from each solar cell panel 111 is converted into an AC voltage. This is sent out onto the power line 103 and supplied to the link control panel 105.

As a result, the solar power generation system 1
01, the DC wiring work part is reduced, the wiring work cost is reduced, and the power generation units 102a to 102a to
The efficiency of the 2n design is reduced, and the overall system construction cost is reduced.

[0010]

By the way, in the above-mentioned conventional solar power generation system 101, an intelligent function is added to the monitoring station 109 provided in each of the power generation units 102a to 102n, and the monitoring device 10 is provided.
6 to check whether a normal response signal (for example, a soundness confirmation signal such as a heartbeat signal) is output from the monitoring station 109 of each of the power generation units 102a to 102n.
9 controls each inverter device 110 to convert the DC voltage output from each solar cell panel 111 into an AC voltage, so that the monitoring station 109 provided in each of the power generation units 102a to 102n operates. Must be supplied with the necessary power to do so.

For this reason, the conventional solar power generation system 10
1, even when some of the power generation units 102a to 102n are not generating power, the system power supply line 108
Thereby, a part of the AC voltage output from the coordination control panel 105 is guided to all the power generation units 102a to 102n,
Each of the power generation units 102a to 102n must be kept in an operating state, and there is a problem that power is wasted correspondingly.

In view of the above circumstances, according to the present invention, a power generation unit that is not generating power can be stopped and the power consumption of this power generation unit can be reduced to zero. It is an object of the present invention to provide a distributed power supply system capable of greatly reducing power consumption.

Further, according to the present invention, it is possible to determine whether or not each of the power generation units is operating normally even if the power generation units that are not generating power are stopped. When something goes wrong,
It is an object of the present invention to provide a distributed power supply system capable of accurately detecting this.

[0014]

In order to achieve the above object, according to the present invention, a plurality of power generation units are provided.
A monitoring station that is provided for each power generation unit and monitors the operation of each power generation unit using the power obtained by the power generation unit of each power generation unit as a power source; and a control station that is provided for each power generation unit and controls each of the monitoring stations. And an inverter device that converts a DC voltage output from the power generation unit into an AC voltage and supplies the AC voltage to a load.

According to a second aspect of the present invention, in the distributed power supply system according to the first aspect, each of the monitoring stations compares a power generation schedule of each power generation unit with an operation status of each power generation unit, and based on the comparison result. And a determination means for determining whether each power generation unit is operating normally.

According to the first aspect of the present invention, each monitoring station provided for each power generation unit is operated using each DC voltage obtained by the power generation unit of each power generation unit. Under monitoring, each inverter unit provided for each power generation unit is operated to convert a DC voltage output from each power generation unit into an AC voltage and supply the AC voltage to a load, thereby generating power without generating power. Shutting down the unit reduces the power consumption of this power generation unit to zero, thereby greatly reducing the amount of power consumed by the entire system.

According to the second aspect, each monitoring station compares the power generation schedule of each power generation unit with the operation status of each power generation unit, and based on the comparison result, determines whether each power generation unit is operating normally. By making the determination, even if the power generation unit that is not generating power is stopped, it is possible to determine whether or not each power generation unit is operating normally, thereby when any of the power generation units becomes abnormal. , Accurately detect this.

[0018]

FIG. 1 is a block diagram showing an example of a photovoltaic power generation system using an embodiment of a distributed power supply system according to the present invention.

The solar power generation system 1 shown in FIG. 1 integrates a plurality of power generation units 2a to 2n that take in sunlight to generate an AC voltage and the AC voltage output from each of the power generation units 2a to 2n. A power line 3, a link control panel 5 for linking an AC voltage combined by the power line 3 with an AC voltage supplied from a commercial power supply 4 and supplying the AC voltage to a load, and a central monitoring room or the like. , A monitoring device 6 for monitoring the operation status of each of the power generation units 2a to 2n, and a network 7 for connecting the monitoring device 6 and each of the power generation units 2a to 2n.
Each of the power generation units 2a to 2n is operated by the DC voltage obtained by each of the 2n solar cell panels 11, and the monitoring device 6 controls each of the power generation units 2a to 2n.
While monitoring 2n, the AC voltage output from each of the power generation units 2a to 2n is led to the link control panel 5 by the power line 3, and this AC voltage is linked to the AC voltage supplied from the commercial power supply 4 to the load. Supply.

The monitoring device 6 is arranged in a central monitoring room or the like, and each of the power generation units 2a to 2n
And a process of periodically supplying a power generation schedule to each of the power generation units 2a to 2n, a process of ascertaining the operating status of each of the power generation units 2a to 2n, and a process of displaying the processing contents on a screen. CPU device 8 to perform
A keyboard device 9 for controlling the operation of the CPU device 8; and a display device 10 for displaying the processing contents of the CPU device 8 on a screen. Power generation units 2a to 2n
Is generated and transmitted over the network 7 to be supplied to each of the power generation units 2a to 2n. Further, at a preset cycle, a request request (for example,
Health request signal, etc.)
The power generation units 2a to 2n are supplied to the power generation units 2a to 2n, and information (for example, a heartbeat signal) indicating the operation status output from each of the power generation units 2a to 2n is taken in to operate the power generation units 2a to 2n. Monitor the situation,
The operation status and the like of each of the power generation units 2a to 2n obtained by this monitoring operation are displayed on a screen so that the operator can grasp it.

The network 7 includes a monitoring device 6 and
It is composed of electric wires or optical cables that support communication with each of the power generation units 2a to 2n, various communication control devices that adjust signals flowing through these electric wires or optical cables, and the like. When information is output, it is taken in and supplied to each of the power generation units 2a to 2n, and when a request signal for requesting an operation status or the like is output from any of the monitoring device 6 or each of the power generation units 2a to 2n, This is taken in and supplied to each of the power generation units 2a to 2n. When information indicating the operation status and the like is output from each of the power generation units 2a to 2n, this is taken in and each of the power generation units 2a to 2n is taken in.
To 2n, the monitoring device 6 and the like.

The power line 3 is composed of electric wires wired so as to connect the link control panel 5 and the power generation units 2a to 2n.
Are combined into one and supplied to the coordination control panel 5.

The coordination control panel 5 includes a power comparison unit that compares the power value of the AC voltage supplied through the power line 3 (power generation amount) with the power amount required by the load (power consumption amount). ,
Based on the comparison result of the power comparison unit, when “power generation amount ≧ power consumption amount”, the AC voltage supplied via the power line 3 is supplied to the load, and “power generation amount <power consumption amount” is satisfied. At one time, an AC voltage supplied from the commercial power supply 4 is added to the AC voltage supplied via the power line 3 to obtain a necessary amount of electric power, and then a linking unit for supplying the required amount of electric power to the load is provided. In addition, one AC voltage combined by the power line 3 and an AC voltage supplied from the commercial power supply 4 are linked to generate an AC voltage of a power amount required by the load, and the generated AC voltage is supplied to the load. Supply.

Each of the power generation units 2a to 2n receives a solar light and generates a DC voltage.
1 and when the current value of the DC voltage obtained by the solar cell panel 11 is equal to or greater than a predetermined current value, at a timing synchronized with the voltage change of the AC voltage flowing on the power line 3;
An inverter device 12 that converts a DC voltage output from the solar cell panel 11 into an AC voltage and sends out the obtained AC voltage onto the power line 3;
The monitoring device 6 is operated by the weak DC voltage output from the power supply, communicates with the other power generation units via the network 7 and grasps the operation status of the other power generation units, and is supplied via the network 7. And a monitoring station 13 for monitoring and controlling the operation of the inverter device 12 based on an instruction (for example, a power generation schedule or the like) provided by the solar cell panel 11. The monitoring station 13 is operated by the DC voltage obtained by the solar cell panel 11. The monitoring device 6 communicates with another power generation unit, and grasps the operation status of the other power generation unit based on the communication result.
(For example, a power generation schedule, etc.), the inverter device 12 is monitored and controlled to convert a DC voltage output from the solar cell panel 11 into an AC voltage, and the obtained AC voltage is converted into a power line. 3 on top.

In this case, as shown in FIG. 2, each monitoring station 13 includes a communication unit 14 for communicating with other power generation units and the monitoring device 6 via a network 7, and a CPU circuit for performing various information processing. A CPU having an OS (Operating System) defining the basic operation of the CPU circuit, a ROM circuit storing constant data and the like, a RAM circuit used as a work area of the CPU circuit, etc.
Unit 15 and information used by the CPU unit 15 (such as the power generation schedule of each of the power generation units 2a to 2n).
Table 16 for storing the
A schedule receiving process for giving an operation procedure to the circuit, communicating with the monitoring device 6 via the communication unit 14, and taking in the power generation schedule of each of the power generation units 2a to 2n, and the own power generation unit obtained by the schedule reception process , An inverter control process for controlling the inverter device 12 of its own power generation unit based on the power generation schedule for the power generation unit, a communication with the other power generation unit, the operation status of the other power generation unit is taken in, and the operation table 16 is stored in the operation table 16. Processing, the operation status of each of the other power generation units obtained by communicating with each of the other power generation units is compared with the power generation schedule of each of the other power generation units stored in the operation table 16, and the other power generation units are compared. Failure determination processing to determine whether or not the power supply has failed, one of the other power generation units has failed When and, and an application program 17 to perform an alarm generation process of generating an alarm (warning).

After the sunlight is received by the solar cell panel 11, the CPU unit 15, the communication unit 14, and the like are operated between the time when the sunlight is no longer received and the time when the sunlight is no longer received.
A schedule reception process and an inverter control process defined in the application program 17 are performed to convert a DC voltage output from the solar cell panel 11 into an AC voltage and send the AC voltage to the power line 3, and a monitoring process.
By performing a failure presence / absence determination process, an alarm generation process, and the like, when an abnormality occurs in another power generation unit, the network 7, or the like, the abnormality is detected and notified to an operator.

At this time, based on the power generation schedule of each of the power generation units 2a to 2n output from the monitoring device 6, FIG.
As shown in the table, each operation table 16 of each monitoring station 13 includes a station number indicating the number of each power generation unit 2a to 2n, and an operation schedule indicating whether each power generation unit 2a to 2n is to generate power on the day. Is written, each time there is a response from each of the power generation units 2a to 2n, the power generation unit 2a
A message indicating whether or not ~ 2n is generating power is written, and these operation schedules are compared with the message,
Based on the contents of the comparison, the current state indicating the presence or absence of an abnormality in each of the power generation units 2a to 2n and the determination indicating the failure state of each of the power generation units 2a to 2n written as abnormal in the current state are written.

Next, the operation of this embodiment will be described with reference to the block diagrams shown in FIGS.

First, when sunlight is received by each solar cell panel 11 constituting each of the power generation units 2a to 2n, each of the power generation units 2a to 2n is constituted by the DC power output from each solar cell panel 11. Power is supplied to the monitoring stations 13 that are operating, the operation of each monitoring station 13 is started, and the RAM circuit of the CPU unit 15 provided in each monitoring station 13 stores
As shown in FIG. 4, a health data section 18, a scheduler section 19, and a determination section 20 are created.

Thereafter, the power generation schedule written in the operation table 16 is looked up by the scheduler section 19 of the CPU section 15 provided in each monitoring station 13 of each of the power generation units 2a to 2n, and each monitoring station is looked up. Power generation unit 2 provided with 13
When the power generation start times a to 2n have elapsed and the current value of the DC voltage output from the solar cell panel 11 has reached a current amount sufficient to perform the orthogonal / AC conversion, each monitoring station 13 causes each inverter to operate. Each of the devices 12 is controlled, and a DC voltage output from each solar cell panel 11 is converted into an AC voltage, which is supplied to the load through a route of the power line 3 → the link control panel 5 → the load.

In parallel with this operation, the soundness data sections 18 provided in the respective power generation units 2a to 2n are sequentially activated, and the activated soundness data sections 18, for example, Soundness data part 1 of power generation unit 2a
8 outputs a request signal (for example, a soundness request signal or the like) for requesting an operation state and the like,
4 on the network 7, and in response to the request signal, the other power generation units 2b to 2b.
n monitoring stations 13 from each of the power generation units 2b to
When the message information indicating the operation status of 2n is transmitted, it is taken in via the network 7 and written on the operation table 16 of the power generation unit 2a.

Then, the determination unit 20 of the power generation unit 2a sends the power generation schedules of the other power generation units 2b to 2n written in the operation table 16 of the power generation unit 2a and the power generation units 2b to 2n. The current operation status is compared. Each power generation unit 2b ~
When the operation status of each of the power generation units 2b to 2n matches the power generation schedule of each of the power generation units 2b to 2n,
Even if n is not operating, it is determined that the stop is instructed by the power generation schedule, and it is determined that each of the power generation units 2b to 2n is operating normally. When there is a power generation unit that does not match the power generation schedule of each of the power generation units 2b to 2n, it is determined that some abnormality has occurred in this power generation unit, the network 7, or the like, and an alarm is generated. Then, the station number of the stopped power generation unit is notified to the operator.

In parallel with the above-mentioned operation, the keyboard device 9 of the monitoring device 6 is operated by the operator in the central monitoring room, and the amount of electric power required on the load side and the electric power supply time required for the electric power. When a change instruction such as is input, a new power generation schedule of each of the power generation units 2a to 2n is determined by the CPU device 8 constituting the monitoring device 6 based on the power amount, the power supply time, and the like.
This determination result is displayed on the display device 10, and
The determination result is sent out on the network 7 and taken into the monitoring station 13 of each of the power generation units 2a to 2n, and the determination results of each of the power generation units 2a to 2n written on the operation table 16 provided in each of the monitoring stations 13 are provided. The power generation schedule is updated.

When the intensity of sunlight received by the solar cell panel 11 provided in each of the power generation units 2a to 2n becomes lower than the intensity required for performing DC / AC conversion, or Power generation units 2a to 2n
When the power generation end time of each of the power generation units 2a to 2n elapses according to the power generation schedule written in the operation table 16 of the power generation unit 2, this is detected by the monitoring station 13 of each of the power generation units 2a to 2n. / The AC conversion operation is stopped.

Thereafter, the intensity of sunlight received by the solar cell panel 11 provided in each of the power generation units 2a to 2n further decreases and is output from the solar cell panel 11 until it becomes almost zero. Each monitoring station 13 provided in each of the power generation units 2a to 2n continues to operate by the DC voltage, and each solar cell panel 11
When the current value of the DC voltage output from becomes almost zero, the monitoring station 13 of the power generation unit corresponding to the solar cell panel 11 whose current value becomes zero stops operating.

As described above, in this embodiment, each of the power generation units 2a to 2n is operated by the electric power obtained by each of the solar cell panels 11 of each of the power generation units 2a to 2n. While monitoring the power generation units 2a to 2n,
The AC voltage output from 2n is guided to the link control panel 5 by the power line 3, and the AC voltage and the AC voltage supplied from the commercial power supply 4 are linked and supplied to the load.
For this reason, among the power generation units 2a to 2n, the power generation units that are not generating power can be stopped, and the power consumption of this power generation unit can be reduced to zero, thereby greatly reducing the power consumption used by the entire system. Can be reduced.

In this embodiment, the DC voltage power required to operate each monitoring station 13 is reduced to the DC voltage power required to perform the DC voltage / AC voltage conversion operation of each inverter device 12. Compared with the fact that the current value of the DC voltage output from the solar cell panel 11 is not a sufficient current value for the DC voltage / AC voltage conversion operation of the inverter device 12 by utilizing the extremely small amount, Immediately after the DC voltage is output from the solar cell panel 11 until the DC voltage is no longer output from the solar cell panel 11, that is, until the sun rises above the horizon and sinks below the horizon. As a result, a DC voltage having a small current value, which was conventionally wasted, can be effectively used.

Further, in this embodiment, the monitoring unit 6 controls each power generation unit 2a based on the amount of power required on the load side, the power supply time required for power, and the like.
Ｎ2n of the power generation schedule, and the determined contents are registered in the operation table 16 of each monitoring station 13,
The power generation schedules of the power generation units 2a to 2n registered in the operation table 16 and the power generation units 2a
To the operation status of each power generation unit 2a
~ 2n are not operating according to the power generation schedule,
When this was detected, an alarm was generated.
Therefore, even if a request is issued from one of the power generation units 2a to 2n, for example, the power generation unit 2a, information indicating the operation status is sent from any of the other power generation units 2b to 2n, for example, the power generation unit 2n. When not coming
It is possible to determine whether the power generation unit 2n has failed, whether a part of the network 7 has failed, or has stopped generating power at night or the like, and thereby, the other power generation units 2b to 2n can be determined. When any of the power generation units becomes abnormal, the power generation unit is accurately detected, and among the other power generation units 2n to 2n, the resting power generation unit is put into an operating state to replace the failed power generation unit 2n. Can be done.

In the above-described embodiment, the power generation units 2a to 2n are caused to generate power according to the power generation schedule created by the monitoring device 6. However, each of the power generation units 2a to 2n is provided with a solar cell. Panel 1
1 to determine whether or not the current value of the DC voltage output from 1 is a current value sufficient to perform DC voltage / AC voltage conversion, and determine whether the current value of the DC voltage output from each solar cell panel 11 is DC voltage / AC When the current value is sufficient to perform the voltage conversion, the monitoring station 1 of each of the power generation units 2a to 2n
This is detected by 3 and it is determined that power generation is possible. Based on the determination result and the operation status of other power generation units,
Until the amount of power required for the load is reached,
DC voltage / AC voltage conversion may be performed every 2n.

Further, in the above-described embodiment, the solar power generation system 1 that receives sunlight and generates electric power is taken as an example.
Although the distributed power generation system according to the present invention has been described, the distributed power generation system according to the present invention may be applied to a wind power generation system that generates power by receiving wind.

[0041]

As described above, according to the present invention, in the distributed power supply system according to the first aspect, the power generation unit that is not generating power is stopped to reduce the power consumption of this power generation unit to zero. As a result, the amount of power consumption used in the entire system can be significantly reduced.

In the distributed power supply system according to the second aspect, it is possible to determine whether or not each power generation unit is operating normally even if the power generation unit that is not generating power is stopped. When any of them becomes abnormal, it can be accurately detected.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of a photovoltaic power generation system using an embodiment of a distributed power supply system according to the present invention.

FIG. 2 is a block diagram showing a detailed circuit configuration example of each monitoring station shown in FIG.

FIG. 3 is a schematic diagram showing an example of operation contents of each power generation unit written in each operation table shown in FIG. 2;

FIG. 4 is a schematic diagram showing an example of a monitoring operation of each monitoring station shown in FIG. 1;

FIG. 5 is a block diagram illustrating an example of a conventionally known solar power generation system.

[Explanation of symbols]

 1: solar power generation system 2a to 2n: power generation unit 3: power line 4: commercial power supply 5: link control panel 6: monitoring device 7: network 8: CPU device 9: keyboard device 10: display device 11: solar cell panel 12 : Inverter device 13: Monitoring station 14: Communication unit 15: CPU unit 16: Operation table 17: Application program 18: Health data unit 19: Scheduler unit 20: Judgment unit

Claims (2)

[Claims] 1. A plurality of power generation units, a monitoring station provided for each power generation unit and monitoring operation of each power generation unit using electric power obtained by a power generation unit of each power generation unit as a power supply, An inverter device provided for each of the monitoring stations and converting a DC voltage output from the power generation unit into an AC voltage and supplying the AC voltage to a load under the control of each monitoring station. system. 2. The distributed power supply system according to claim 1, wherein each monitoring station compares a power generation schedule of each power generation unit with an operation status of each power generation unit, and based on the comparison result, generates each power generation unit. Determining means for determining whether or not the unit is operating normally.