JP2011223853A - System link/parallel-off system for distributed power source - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system link/parallel-off system for a distributed power source in which, when single operation of a consumer-side distributed power unit is detected, power is supplied to a load circuit from the distributed power unit without supplying power from the distributed power unit to a commercial power supply system but when abnormality or the like of the commercial power supply system is recovered, on the other hand, power is promptly obtained from the commercial power supply system, thereby supplying power to a consumer side continuously in accordance with power generation of the distributed power unit varying with the passage of time, without damaging safety, ease, and comfort of a consumer.SOLUTION: A system link/parallel-off system includes: a cable switchgear for linking or making parallel-off on both a load circuit and a distributed power supply system with a commercial power supply system; and a system protecting means for outputting a commercial power supply system failure detecting signal or a recovery detecting signal to the cable switchgear when it is detected that power supply from the commercial power supply system is intercepted or recovered. The cable switchgear is turned off or on with the signal as a trigger signal, thereby feeding power to the load circuit at all the time.

Description

The present invention relates to a distributed power supply that supplies power to a load circuit from both the distributed power supply system and the distributed power supply system by connecting or disconnecting the distributed power supply system to the commercial power supply system. The present invention relates to a system interconnection disconnection system.

Recently, the distributed power supply system is spreading. For example, install distributed power sources such as solar cells, fuel cells, micro gas turbines, wind power generators, etc. in close proximity to user loads, such as ordinary homes, apartment houses, and small businesses, to supply power to users. There are many.

FIG. 2 of Patent Document 1 shows an example of a distributed power supply system using a solar cell as a power generation source. In FIG. 2, the distributed power supply system includes a solar cell array 1 and power conversion means 4 incorporating an inverter 24 that converts DC power output from the solar cell array 1 into AC power. This power conversion means 4 detects the disconnection of the circuit breaker 25 that disconnects the distributed power from the commercial power system 11 and the circuit breaker 26 of the commercial power system 11 based on frequency fluctuations and voltage fluctuations, and disconnects the circuit breaker 25. The system interconnection protection device including the isolated operation detecting means 27 is built in.

And as disclosed in Patent Document 2, the inverter provided in the solar power generation device has a function of controlling the AC output voltage of the inverter to a constant voltage by the included control circuit, that is, a function of suppressing a voltage increase, And has a function of detecting isolated operation.

As for the function for detecting the independent operation of the inverter, as shown in Patent Document 2, when a system power failure occurs due to construction or the like while the output voltage of the inverter is connected to the power system, the inverter Is to stop. If the inverter remains in an operating state, the inverter output voltage is applied to the construction section of the power system due to the independent operation of the inverter, and there is a risk of electric shock to construction workers and the like. Therefore, the function of detecting the isolated operation is to detect a change in voltage due to the application of the output voltage of the inverter in the system power failure state and stop the inverter.

Regarding the detection function of the isolated operation, particularly when a plurality of private power generators are connected to the same pole transformer in the power system, whether or not this detection function works effectively is an important issue. In other words, if two private power generators are installed in the same area (called “bank”) where the pole transformer of the power system is the same, even if a system power failure occurs, When power is supplied, it may be difficult for the other inverter to detect a change in voltage due to the application of the output voltage and stop the inverter. Therefore, it is necessary to confirm in advance whether or not the function for detecting an isolated operation surely works between an existing private power generation device and a new private power generation device in the same bank. This confirmation work is often performed exclusively by an electric utility.

JP 2002-152976 A JP 2008-77369 A

As described above, in the spread of the solar power generation apparatus, since commercial power is conventionally supplied from an electric power company, power is generated on the consumer side. Therefore, power generation on the electric power company side and the consumer side is performed. Coordination and understanding of the situation will be important. In particular, in the case where two or more photovoltaic power generation devices are installed in the same bank, a single operation in which only the power generation device on the consumer side continues the power generation operation in a state where a system power failure on the electric power company side has occurred. If it continues, the output power is applied to the construction section of the power system on the electric utility side, and there is a risk of electric shock to construction workers, etc. When the isolated operation is detected, the operation of the inverter is stopped and the electric utility It has become an important issue to provide a function to prevent the output voltage from the photovoltaic power generator from being applied to the power system on the side.

However, when the isolated operation is detected, the output voltage is not applied to the power system on the electric utility side by stopping the inverter. Since the power supply is not performed, for the consumer, when the commercial power fails, the power supply from the solar power generation device is also stopped, resulting in a total power failure. If the system is shut down immediately after a power failure occurs on the electric utility side, the generated power cannot be used effectively even if the power generation operation of the solar power generation system is normal, and the power failure occurs. Along with this, it is conceivable that the safety, security and comfort of consumers' lives will be reduced. In addition, when a power failure on the electric utility side is restored, it is desirable that commercial power be supplied to the load circuit promptly.

Therefore, the present invention has been made in view of the above problems, and the power supply to the customer side is interrupted due to a power failure or failure in the system on the electric utility side, and the independent operation of the distributed power supply device such as a solar power generation device is possible. If detected, the power supply from the distributed power supply is supplied to the electric utility side system to prevent an electric accident such as an electric shock from a construction worker in the electric utility side system. While the power supply of the distributed power supply is supplied to the load circuit, when the grid on the electric utility side is restored, the power supply is immediately obtained from the grid on the electric utility side to ensure the safety and security of consumers. A system of distributed power sources that can continuously supply commercial power or commercial power and distributed power sources to consumers according to the amount of power generation that changes over time of the distributed power devices without sacrificing comfort Providing an interconnection system For the purpose of theft.

A system connection disconnection system of a distributed power source according to the present invention is configured to solve the above-described problems, and power supply to a load circuit is connected to a power supply system and the power supply system. A system connection disconnection system of a distributed power source that is performed from both of the distributed power systems in which the system is connected, and the system connection disconnection system of the distributed power source is connected to an electric path from the commercial power system to a load circuit. An electric circuit switch that interconnects or disconnects both the load circuit and the distributed power supply system from the commercial power supply system, and a system connected disconnection system of the distributed power supply from the commercial power supply system. When it is detected that the power supply has been interrupted or the power supply from the commercial power system has been restored, and it is detected that the power supply from the commercial power system has been interrupted, a commercial power system power failure detection signal is generated. Open circuit System protection means for outputting a commercial power system restoration detection signal to the circuit switch when it is detected that the power supply from the commercial power system is restored. The circuit switch receiving the commercial power system power failure detection signal output from the means opens the contact of the circuit switch using the commercial power system power failure detection signal as a trigger signal, and the load circuit and the distributed power source While the system is disconnected from the commercial power supply system, the circuit switch that has received the commercial power system recovery detection signal, by using the commercial power system recovery detection signal as a trigger signal, the contact that the circuit switch has, Both the load circuit and the distributed power supply system are connected to a commercial power supply system, and power supply to the load circuit is continuously performed from the distributed power supply alone or from both the commercial power supply and the distributed power supply. It may constitute the system interconnection disconnection system of the distributed power supply as a feature to keep the power supply to the load circuit by being.

According to such a configuration, when the commercial power system side fails and the isolated operation of the distributed power system on the consumer side is detected, the circuit switch that receives the commercial power system power failure detection signal (single operation detection signal) The commercial power system side can be disconnected from the load circuit and the distributed power system side, and the power source from the distributed power system is not applied to the commercial power system side. When power failure recovery on the commercial power system side is detected, the commercial power system side and load circuit are again connected to the commercial power system side by the circuit switch that receives the commercial power system recovery detection signal. In addition, by connecting the power supply system to the distributed power supply system, power can be quickly obtained from the commercial power supply system on the electric utility side, so that electric accidents such as electric shocks by construction workers on the commercial power supply system side can be prevented. While, consumer safety, safe, without sacrificing comfort, it is possible to provide a system interconnection disconnection system of distributed power sources can be performed continuously power supply from the distributed power demand side.

Further, in the system connection disconnection system of the distributed power source according to the present invention, the system connection disconnection system of the distributed power source is provided in a power system on the electric power supplier side supplying the commercial power source, Provided in a commercial power supply system that detects that the power supply in the power system has been stopped or has recovered, and outputs a cut-off signal for stopping the power supply to another power system or a recovery signal for recovery A transfer cutoff signal recovery signal receiving device that receives the transfer cutoff signal or recovery signal output from the transfer cutoff recovery signal transmission device and outputs the commercial power system power failure detection signal or commercial power system recovery detection signal to the circuit switch. System protection means provided in the distributed power supply system for providing a trigger signal for driving an electric circuit switch that interconnects or disconnects the load circuit and the distributed power supply system from the commercial power supply system. Instead of the commercial power system power failure detection signal or the commercial power system recovery detection signal output from the transmission power interruption system recovery detection signal or the commercial power system recovery detection signal output from the transfer interruption signal recovery signal receiver The power line switch that has received the commercial power system power failure detection signal or the commercial power system restoration detection signal output from the transfer interruption signal restoration signal receiving device is the commercial power system power failure detection signal or the commercial power system restoration detection signal. The circuit connection solution of the distributed power supply is characterized in that the load circuit and the distributed power system are both disconnected or connected from the commercial power system by opening or closing the contact of the circuit switch using the signal as a trigger signal. A column system should be configured.

According to such a configuration, a transfer interruption signal or a restoration signal from the electric utility side is used as a trigger signal for interruption or restoration of the circuit switch, so that a power failure occurs as well as a power failure. Even before the start of the operation, if a power outage is likely to occur due to lightning, etc., or if construction is planned in the commercial power supply system, etc. While the distributed power supply system can be disconnected, when a power failure or the like in the commercial power supply system is restored, the distributed power supply system is quickly connected to the commercial power supply system, and commercial power is supplied to the load circuit. It is possible to provide a system connection disconnection system of a distributed power source that can be used.

Moreover, the system connection disconnection system of the distributed power supply which concerns on this invention arrange | positions the electric circuit switch of Claim 1 or Claim 2 in the electric wire drawing part vicinity, and is on the load side of the said electric circuit switch. A main switch connected to the electric circuit switch, a bus connected to the load side of the main switch, a plurality of branch switches branching power from the bus to each load circuit, and connected to the bus A distributed distribution power system switch that is provided with a residential distribution board, and when the circuit switch operates, the secondary side including the main switch from the commercial power system It is also possible to configure a system connection disconnection system of distributed power sources characterized in that all of the circuits are disconnected or connected.

According to such a configuration, the distributed power system interconnection system that combines the electrical safety on the commercial power system side, the safety, security and comfort on the consumer side without significantly changing the current distribution wiring. Can be easily introduced in dwelling units such as ordinary households and apartment houses, small business establishments, and the like.

The distributed power supply system according to the present invention further includes a power generating power calculating means for calculating power that can be generated by the distributed power system, and a current flowing through the branch circuit through the switch for the distributed power system. A current monitoring means for measuring, a current monitoring means for measuring a current flowing through each branch circuit, a current value obtained from the current monitoring means, and a power consumption value in the load circuit at that time, and a calculation of the power that can be generated Comparing with the power generation possible power value obtained by the means to obtain a usable power value with respect to the power generation possible power value, calculating a ratio of the usable power value with respect to the power generation possible power value, the ratio is below a predetermined ratio A load circuit controller that outputs a signal for shutting off the branch circuit and performs control to reduce power consumption in the branch circuit. When the load circuit and distributed power supply system are disconnected from the source system, the power consumption in the load circuit is controlled so that the power generation possible value in the distributed power system always has a margin for the power consumption value in the load circuit. A distributed power supply system may be configured as a feature.

According to such a configuration, it is possible to provide a distributed power supply system that can continuously supply power from the distributed power supply according to the amount of power generation that changes over time of the distributed power supply device.

As described above, according to the present invention, when the power supply to the customer side is interrupted due to a power failure or failure in the system on the electric utility side, and a single operation of a distributed power supply device such as a solar power generation device is detected. The power supply from the distributed power supply is supplied to the electric utility side system to prevent an electric accident such as an electric shock from a construction worker in the electric utility side system, and distributed to the load circuit. When the power supply system is restored while the power supply of the type power supply is supplied, the power supply must be quickly obtained from the power supply system and the safety, security, and comfort of the consumer may be impaired. In addition, a distributed power system interconnection system that can continuously supply power from the commercial power source or the commercial power source and the distributed power source to the customer side according to the amount of power generation that changes over time of the distributed power device. Can be provided.

The schematic block diagram of the grid connection disconnection system of the distributed power source which shows 1st Embodiment is shown. The schematic block diagram of the grid connection disconnection system of the distributed power supply which shows 2nd Embodiment is shown. The block block diagram of the distribution board for houses used for the grid connection disconnection system of the distributed power supply which shows 3rd Embodiment is shown. The block diagram of the distribution board for houses concerning the embodiment is shown. The schematic block diagram of the distributed power supply system which shows 4th Embodiment is shown.

Next, an embodiment of the present invention will be described in detail with reference to FIGS.

(First embodiment)
FIG. 1 is a schematic configuration diagram showing a first embodiment of a system interconnection disconnection system of a distributed power source according to the present invention. As shown in FIG. 1, in the system connection disconnection system 1 of the distributed power supply according to the present embodiment, power supply to the load circuit 300 is performed from both the commercial power supply system 100 and the distributed power supply system 200. Is.

As the load circuit 300, a circuit to which an electrical device is connected is assumed, and a circuit in which input power is distributed to a plurality of branch circuits using a distribution board, such as a dwelling unit such as a detached house or an apartment, A single circuit is used. In addition to residences, circuits in various places such as offices and factories are applicable.

In the electric circuit 10 from the commercial power supply system 100 to the load circuit 300, an electric circuit switch 400 is interposed. When viewed from the commercial power supply system 100, the load circuit 300 and the distributed power supply system 200 are arranged on the downstream side (secondary side) of the circuit switch 400. When the circuit switch 400 operates, both the load circuit 300 and the distributed power supply system 200 are disconnected from or connected to the commercial power supply system 100.

The commercial power supply system 100 is a power supply system on the side of an electric power company such as an electric power company. At present, an AC power distribution system is generally used.

The distributed power supply system 200 is a power supply system provided on the consumer side. Currently, a power distribution system using a DC power source generated from a solar power generation device, a fuel cell, a micro gas turbine, a wind power generation device, or the like is generally used. It is.

Since the power source generated by the distributed power system 200 is a DC power source, an inverter device 210 is provided in the distributed power system 200 in order to convert the DC power source into a power source suitable for a load driven by the AC power source. It is connected. The power converted by the inverter device 210 is supplied to the load circuit 300 through the electric circuit 20.

The inverter device 210 is connected to a system protection means 220 that detects that the power supply from the commercial power system 100 has been interrupted. For example, in the case of a solar power generation device, the system protection means 220 is such that the power supply from the commercial power system 100 is interrupted and the solar power generation device performs an independent operation, like the system protection means used in the power conditioner. It is something to detect.

The system protection means used in a normal power conditioner acts on the inverter device to stop the operation of the inverter device so that the power output of the inverter is not applied to the commercial power system when an isolated operation is detected. In the present embodiment, the system protection means 220 outputs a commercial power system power failure detection signal when it detects that the power supply has been interrupted due to a power failure or construction, etc., and the distributed power source has been operated independently. An output unit that outputs to the outside, and outputs a commercial power system restoration detection signal to the outside when it is detected that the commercial power system has been restored and power has been supplied. A system power failure detection signal or a commercial power system restoration detection signal is output to the electric circuit switch 400 through the signal line 30.

When the commercial power system power failure detection signal or the commercial power system recovery detection signal is input, the electric circuit switch 400 opens or closes the contact device. The electric circuit switch 400 includes a contact device that turns on and off the electric circuit, a contact opening and closing mechanism that opens and closes the contact device, an operation unit that operates the contact opening and closing mechanism from the outside and operates the contact device, and an external signal. An input unit; and a driving unit including a coil and a motor that are driven when the external signal is input and act on the opening / closing mechanism to open or close the contact device.

In such a distributed power grid connection disconnection system, power is supplied to the load circuit 300 from both the commercial power system 100 and the distributed power system 200 in a normal state. When a power failure or the like occurs on the 100 side and the power supply from the commercial power system side is interrupted, if the independent operation of the distributed power system 200 is detected by the system protection means on the consumer side, the commercial power source The circuit switch 400 that has received the system power failure detection signal performs an operation of opening the contact point, and the distributed power system 200 is disconnected from the commercial power system 100 together with the load circuit 300.

Therefore, even if the power supply from the distributed power supply system 200 side is not applied to the commercial power supply system 100 side, and the construction power recovery work or the like is being performed in the commercial power supply system, the construction worker can receive an electric shock. The risk of doing so can be avoided.
In a commercial power system, when multiple distributed power systems are installed in the same area as the pole transformer, in the grid-connected disconnection system of the distributed power system in this application, Since the power supply system is disconnected from the commercial power supply system, it is possible to completely prevent the flow of power generated by other distributed power supply systems. It is possible to prevent the power supply from becoming unstable without being affected by the power generation from other distributed power supply systems in the same bank. On the other hand, when viewed from other distributed power supply systems in the same bank, the number of distributed power supply systems performing isolated operation is reduced, and it is easy to detect the isolated operation.

When the system protection means 220 detects that the power supply from the commercial power system 100 has been restored, a commercial power system restoration detection signal is output from the system protection means 220 and the signal line 30 is In response to the commercial power system restoration detection signal, the circuit switch 400 performs the operation of closing the contact, and links the distributed power system 200 together with the load circuit 300 to the commercial power system 100.

Therefore, when power failure recovery on the commercial power supply system 100 side is detected, both the load circuit and the distributed power supply system are linked to the commercial power supply system, so that power can be quickly obtained from the commercial power supply system side. It is possible to stably supply power without interrupting power supply as much as possible.

In order to detect whether or not the commercial power system 100 side has been restored, a voltage transformer (PT), a voltage detector, or the like that detects that a voltage has been applied to the primary side of the circuit switch 400 is provided. In addition, the system protection means may receive a detection output from the voltage detector or the like via a signal line or the like and detect that the power supply from the commercial power supply system 100 has been restored. Moreover, you may comprise so that not only a recovery state but a power failure state may be detected.

In the system connection disconnection system of the distributed power supply in the present application, when the power supply is interrupted due to a power failure or the like, the distributed power supply system is disconnected from the commercial power supply system together with the load circuit. When the power system is restored, the distributed power system is linked together with the load circuit. For this reason, when the power generation operation of a distributed power source such as a solar power generation device is normal, the power supply state to the load circuit can be continuously maintained regardless of the power supply state in the commercial power supply system, and There is no reduction in safety, security, and comfort, and in the event of a power failure or the like on the commercial power system side, the distributed power supply in the single operation state is not applied to the commercial power system side. It is possible to prevent electrical accidents such as electric shock from the operator.

The safety, security, and comfort of consumers' lives are assumed to be the result of electrical equipment that is operating due to the supply of electricity being stopped when the supply of electricity is interrupted. is doing. For example, security device operation stop caused by power failure, cooking utensil non-operation, lighting fixture off, water pump water supply operation stop, septic tank drainage operation stop, air conditioner operation stop, ventilation device operation stop, Various troubles are expected to occur due to the stop of the operation of the electrical equipment such as the stop of the operation of the server / client computer and the stop of the operation of the modem device / telephone device for using the Internet network. Of course, it is desirable to avoid the stoppage of electrical equipment related to safety as well as comfort.

(Second Embodiment)
FIG. 2 is a schematic configuration diagram showing a second embodiment of a system interconnection disconnection system of a distributed power source according to the present invention. As shown in FIG. 2, in the system interconnection disconnection system 1 of the distributed power source according to the present embodiment, as in FIG. 1, the power supply to the load circuit 300 is the commercial power system 100 and the distributed power system 200. It is done from both.

Here, in the first embodiment, a power failure and recovery in the commercial power system 100 are detected on the distributed power system 200 side. However, in the present embodiment, on the commercial power system 100 side. The provided transfer cutoff signal recovery signal receiving device 110 receives the transfer cutoff signal or recovery signal output from the transfer cutoff recovery signal transmission device 101 on the electric utility side, and receives the respective signals. A commercial power system power failure detection signal or a commercial power system restoration detection signal is input from the receiving device 110 to the electric circuit switch 400 to cause the electric circuit switch 400 to be shut off or turned on.

Here, the transfer interrupting device generally means that when a power failure or power recovery in the power distribution system on the electric utility side is detected, the power generation device in the power distribution system provided downstream from the power distribution system operates. This is a device that outputs a signal for instructing to disconnect or stop the power generator from the power distribution system in order to prevent a single operation state from being continued (see paragraph No. 0021 of JP-A-2004-187442). The transfer interrupting device includes a monitoring unit that monitors an operating state of the substation circuit breaker, and a signal that injects a disconnection command signal into the distribution system when the monitoring unit determines that the substation circuit breaker is open. It consists of injection means. And when the signal receiving means for receiving the disconnection command signal and the signal receiving means receive the disconnection command signal, the control means for disconnecting the power generator from the distribution system by performing an opening operation of the breaker for the power generator As a result, the breaker for the power generator is opened. The transfer cut-off signal output from the transfer cut-off device is injected into the distribution system as a pulse signal having a predetermined frequency that can be distinguished from the commercial power supply frequency.

In addition to the configuration of the transfer cut-off device, the transfer cut-off signal restoration signal transmission device 101 in the present invention detects by the monitoring means that the power supply in the electric power system on the electric utility side has stopped and the power supply has been restored. Thus, it is an apparatus provided with output means for outputting a cut-off signal for stopping power supply to another power system or a recovery signal for recovery, and is provided in a power system on the electric utility side that supplies commercial power.

Since the transfer cut-off signal recovery signal transmission device 101 is provided in the distribution system on the electric power provider side, the transfer cut-off signal recovery signal transmission device 101 and the transfer cut-off recovery signal reception device 110 provided in the vicinity of the consumer side are provided. The electric circuit 10 is often over a long distance. For this reason, similar to the above-described transfer cutoff device, the cutoff signal and the recovery signal output from the transfer cutoff signal restoration signal transmission device 101 are set as a pulse signal having a predetermined frequency that can be distinguished from the commercial power supply frequency to the distribution system. However, if it is assumed that each signal is attenuated during transmission through the power distribution system and cannot be taken out, for example, by passing through a transfer path or a relay transformer. Alternatively, a communication line for transmitting a signal may be provided in parallel with the power distribution system to connect the transfer cutoff signal restoration signal transmission device 101 and the transfer cutoff signal reception device 110.

In addition, since providing communication lines in all paths may increase costs, signal receiving means for connecting communication lines to a power pole in the vicinity where the transfer interruption signal restoration signal receiving apparatus 110 is installed is provided. In addition, a signal injection means for injecting a signal into a short-distance power distribution system from the signal receiving means to the transfer cutoff recovery signal receiving device 110 is provided, while an injection signal receiving means is provided in the transfer cutoff recovery signal receiving device 110. The signal from the transfer cutoff signal recovery signal transmission device 101 may be transmitted to the transfer cutoff signal reception device 110.

The transfer interruption recovery signal receiving device 110 in this embodiment is interposed in the electric circuit 10 between the commercial power supply system 100 and the electric circuit switch 400, and receives the transfer interruption signal and the recovery signal output by the transfer interruption signal recovery signal transmission device. If the transfer interruption signal is received, a commercial power system power failure detection signal is output to the electric circuit switch 400 through the signal line 31. When a restoration signal is received, a commercial power system restoration detection signal is output to the electric circuit switch 400 through the signal line 31. That is, the transfer interruption signal or the restoration signal from the electric utility side is used as a trigger signal for causing the electric circuit switch to be interrupted or turned on.

Such a distributed power grid connection disconnection system supplies power to the load circuit 300 from both the commercial power system 100 and the distributed power system 200 in a normal state, as in the first embodiment. However, when a power failure or the like occurs on the commercial power supply system 100 side and the power supply from the commercial power supply system side is interrupted, the transfer output from the transfer interruption signal recovery signal transmission device 101 on the electric utility side is performed. By receiving the interruption signal or the restoration signal by the transfer interruption signal receiving device 110 and causing the electric circuit switch 400 to be interrupted or turned on, the distributed power supply system 200 and the load circuit 300 are disconnected from or connected to the commercial power supply system 100. Let

Therefore, by using the transfer cut-off signal or restoration signal from the electric utility side as a trigger signal for cut-off or restoration of the circuit switch, of course, before a power outage occurs in the commercial power system. However, when a power outage is likely to occur due to lightning, etc., or when construction is planned for a commercial power supply system, the distributed power system on the customer side is appropriately selected according to the convenience of the electric power company. In addition, when a power failure or the like in the commercial power system is restored, the distributed power system can be quickly connected to the commercial power system and commercial power can be supplied to the load circuit. .

When it is not desirable for the electric power company to apply power from the distributed power supply system 200 side to the commercial power supply system 100 side, the distributed power supply system can be disconnected, and power failure recovery can be performed in the commercial power supply system. When construction work is being carried out, it is possible to avoid the risk of electric shock of construction workers.
Also, in the commercial power system, when multiple distributed power systems are installed in the same area as the pole transformer, a distributed type is used together with the load circuit using a transfer cut-off signal from the electric utility side. Since the power supply system is disconnected from the commercial power supply system, it is likely to become a problem when performing independent operation detection on the power conditioner side. When there are multiple distributed power supplies in the same bank, they are affected by each other's power generation. There is an advantage that it is not difficult to detect the operation, and the isolated operation can be detected more reliably.

In addition, when a power failure or the like in the commercial power system is restored, the electric circuit switch is turned on based on the restoration signal transmitted from the transfer interruption signal restoration signal transmission device installed on the electric utility side. In the system connection disconnection system of the distributed power supply, the distributed power supply system is disconnected from the commercial power supply system together with the load circuit, while the distributed power supply system is not disconnected from the load circuit. When the power generation operation of the distributed power source is normal, the power supply to the load circuit is continuously maintained by the generated power without reducing the safety, security and comfort of consumers' lives.
In addition, since no power is applied to the commercial power supply system side from the distributed power supply in the single operation state, it is possible to prevent an electrical accident such as an electric shock from a construction worker on the commercial power supply system side.

(Third embodiment)
FIG. 3 is a schematic configuration diagram showing a third embodiment of a system interconnection disconnection system of a distributed power source according to the present invention. The system connection disconnection system 1 of the distributed power source according to the present embodiment is configured by using a residential distribution board 500 as a load circuit. Components similar to those in the first and second embodiments are denoted by the same reference numerals.

In the residential distribution board 500, an electric circuit switch 400 is disposed in the vicinity of a wire lead-in portion from the commercial power supply system side. A main switch 301 is disposed on the load side of the circuit switch 400, and a bus 303 for branching the power supply to a branch circuit and a plurality of branch switches connected to the bus on the load side of the main switch 301. And a distributed power system switch 304 connected to the bus.

The distributed power supply system 200 is connected to an inverter device 210 that converts a DC power supply into an AC power supply. The output of the inverter device 210 is input to the distributed power system switch 304 through the electric circuit 20. Further, the inverter device 210 is connected with a system protection means 220 having a detection means for detecting that the power supply from the commercial power supply system 100 is interrupted or the power supply is restored.

The commercial power system power failure detection signal and the commercial power system restoration detection signal output from the transfer cutoff signal receiver 110 provided on the commercial power system 100 side on the electric utility side are sent to the circuit switch 400 via the signal line 31. Entered. Further, the commercial power system power failure detection signal and the commercial power system restoration detection signal output from the system protection means 220 may be input to the electric circuit switch 400 via the signal line 30. Furthermore, a signal input terminal is provided in the circuit switch 400 so that the commercial power supply system power failure detection signal and the commercial power system restoration detection signal are input from both the transfer interruption signal restoration signal receiver 110 and the system protection means 220, and the transmission interruption is performed. The circuit switch 400 may be configured to operate when receiving a commercial power system power failure detection signal or a commercial power system recovery detection signal from either the signal recovery signal receiving device 110 or the system protection means 220.

FIG. 4 shows a diagram in which the grid-connected disconnecting system 1 of the distributed power source according to the present invention is applied to a residential distribution board 500 specifically. In the case of the residential distribution board 500, there are a current limiter 600 installed by a contract with an electric utility provided in an electric wire lead-in part of a commercial power supply system, and an electric circuit connected to the load side of the current limiter 600 The switch 400, the main switch 301 connected to the load side of the circuit switch 400, the bus (not shown) connected to the load side of the main switch, and each load circuit connected to the bus A branch switch 302 that branches power to the power source, a distributed power switch 304 that is connected to the bus and receives power from the distributed power system, and is provided at each pole on the primary side of the circuit switch 400. Signal receiving means 111, a transfer cut-off signal receiving apparatus 110 to which a signal from the signal receiving means is input, a commercial power system power failure detection signal and a commercial power system restoration detection signal output from the transfer cut-off signal receiving apparatus 110 Is A signal line 30 which is is provided. In this case, the commercial power supply system is connected to the current limiter 600. When the current limiter is not provided, the commercial power supply system is connected to the electric circuit switch 400. The load circuit 300 includes a main switch 301, a bus, a branch switch 302, an electrical device connected to the load side of the branch switch 302, and a distributed power system switch 304.

Here, as the electric circuit switch 400, a remote control relay that receives an external signal input (commercial power system power failure detection signal and commercial power system recovery detection signal) and opens or closes the contact device is used. External signal input is performed via the signal line 30. The signal line 30 is drawn from the side surface of the electric circuit switch to the outside of the electric circuit switch. Further, the input of the distributed power source to the distributed power source switch 20 is performed via the electric circuit 20.

Further, as the signal receiving means 111, a current transformer is used, and the primary side electric wire of the electric circuit switch 400 is inserted into the current transformer, and the electric circuit is connected to the electric circuit by the transfer interruption signal restoration signal transmission device 101. The injected cut-off signal and recovery signal are detected.

When viewed from the commercial power supply system 100, the load circuit 300 and the distributed power supply system 200 are arranged on the downstream side of the electric circuit switch 400. When the circuit switch 400 operates, both the load circuit 300 and the distributed power supply system 200 are disconnected from the commercial power supply system, as in the other embodiments.

(Fourth embodiment)
FIG. 5 is a schematic configuration diagram showing a fourth embodiment of the distributed power supply system according to the present invention. The distributed power supply system 1 according to the present invention disconnects the distributed power supply system together with the load circuit from the commercial power supply system when the power supply is interrupted due to a power failure or the like. In the embodiment, when power is supplied to the load circuit by the distributed power supply system after being disconnected, the power supply to the load circuit is performed so that power can be supplied within the range of power that can be generated by the distributed power supply system. By controlling the power supply, the customer can continuously receive power from the distributed power source according to the amount of power generation that changes over time, without compromising the safety, security, and comfort of the consumer. It can supply power.

In this embodiment, the difference from the third embodiment is that power that can be generated in the distributed power supply device 200 is first measured by the power conversion means 201 that converts the DC power generated in the distributed power supply system into AC power. This means that the power generation possible power calculation means 230 is provided.

Further, the residential distribution board 500 includes a current monitoring unit 306a for measuring a current flowing through the branch circuit through the distributed power system switch 304, a current monitoring unit 306b for measuring a current flowing through each branch circuit, Calculate the power consumption value in the load circuit from time to time based on the current value obtained from the current monitoring means and compare with the power generation possible power value obtained by the power generation possible power calculation means 230 to use the power generation possible power value. While calculating the possible power value, calculate the ratio of the usable power value to the power generation possible power value, and when that ratio falls below the predetermined ratio, output a signal that shuts off the branch circuit and consumes it in the branch circuit. A load circuit controller 305 that performs control for reducing power, and a branch switch 307 that receives and outputs a signal from the load circuit controller. Is that digit.

Here, when the distributed power supply device 200 is a solar power generation device, for example, as the power generation possible power calculation means 230, a calculation for calculating the generated power based on the output voltage and output current of the solar power generation device 200. The microcomputer may comprise the means, the output variable means for changing the output voltage of the solar power generation apparatus 200, and the control means for controlling the output variable means to change the output voltage of the solar power generation apparatus. The control means performs a search operation for searching for an output voltage value at which the generated power calculated by the calculating means is maximized every predetermined time by changing the output voltage of the photovoltaic power generation device by controlling the output variable means. Do. Moreover, it is good to provide and comprise the output part which outputs the generated electric power value data used as the maximum calculated | required by the searched output voltage value outside.

Further, the current monitoring means 306a and 306b may be constituted by a current transformer (CT) that is used by being inserted into the electric circuit and that outputs an output signal corresponding to the magnitude of the current flowing through the electric circuit. In addition to using CT, a Hall element used close to the electric circuit may be used.

The load circuit controller 305 includes a signal input unit to which an output signal output from each of the current monitoring units 306a and 305b and an output signal output from the power generation capability calculation unit 230 are input, and an input signal Is calculated, the usable power value is calculated with respect to the power generation possible power value, the ratio of the usable power value to the power generation possible power value is calculated, and the ratio is equal to or less than a predetermined ratio (preferably, 20% is expected for safety And a branching circuit that outputs a signal for shutting off the branch circuit and outputs a signal for returning the branch circuit when the ratio exceeds the predetermined ratio, and these branches. A signal output unit that outputs a signal for controlling the shutoff / return of the circuit to the outside may be provided.

The load circuit control unit 305 is configured to be substantially compatible with the branch switch of the residential distribution board, and is used by being attached to the branch switch mounting part of the residential distribution board.

The branch switch 307 receives a signal from the load circuit controller and cuts off / in the electric circuit, and is configured using a remote control breaker.

Although not shown, signal lines for transmitting / receiving signals to each other are connected between the load circuit controller 305, the current monitoring means 306a and 306b, the power generating power calculating means 230, and the branch switch 307. It is configured to be turned.

Further, the distributed power system switch 304 is configured by using a leakage breaker. When a distributed power supply system is disconnected from the commercial power supply system together with a load circuit, if a leakage occurs on the distributed power supply system side, the leakage is detected and power is supplied from the distributed power supply system to the load circuit. This is to shut off.

The operation of the distributed power supply system in this embodiment will be described. When the distributed power supply system and the load circuit are disconnected from the commercial power supply system, power is continuously supplied from the distributed power supply system to the load circuit. The load circuit controller 305 obtains the ratio of the usable power value to the power generation power value for each predetermined time interval from the power generation possible power value in the distributed power system and the power consumption value in the load circuit. Blocking / returning control is performed using the ratio (20%) of the above as a threshold value.

When the ratio of the usable power value to the power generation possible power value is larger than the predetermined ratio, the calculation process for obtaining the ratio of the usable power value for each predetermined time interval is repeated without performing the control. When the ratio of the usable power value to the power generation possible power value is equal to or less than the predetermined ratio, a cut-off signal is output from the load circuit controller 305 to the branch switch 307 and consumed as a whole load circuit. Control to reduce power.

Since the power generation value of the distributed power system and the power consumption value of the load circuit are expected to change every moment, such control is repeated, and the power generation power value always has a certain margin It is something to keep in.

As for the branch circuit that performs the shut-off control, the shut-off control may be performed in order for the branch circuits registered in advance in the load circuit controller 305, or from time to time based on the output signal obtained from each current monitoring means 306b. The branch circuit that is expected to have a blocking effect may be configured to perform the blocking control. Here, the expectation of the shut-off effect means that the shut-off operation is performed for a circuit that actually consumes power so that the usable power obtained by the arithmetic processing is increased.

The return control of the branch switch will be described. As for the timing of return control of the branch switch, if the available power is restored immediately when the available power exceeds the predetermined ratio with respect to the power that can be generated, then the power is cut off again when the power that can be generated decreases. It is expected that. In other words, when the electrical equipment connected to the load circuit is viewed, it is temporarily shut off after being shut off, and then immediately shuts off, which is expected to inconvenience the user. For this reason, it is preferable not to perform the return control for a while after the shut-off control.

More preferably, the load circuit controller 305 identifies and stores a time measuring means (RTC: real-time clock), a time when the shut-off / return control is performed, and a target branch switch (load circuit). When the ratio of the usable power value to the power generation possible power value is larger than the predetermined ratio, a sufficient degree (at least several) for the branch switch that has been controlled in the past. It is preferable to perform the return control for the other branch circuit without performing the return control.

Further, providing the current monitoring means 306b in all branch circuits increases the cost. For example, the current monitoring means 306b is not all branch circuits but a part of the branch circuits (about 20%) to be controlled. Current monitoring means 306b is provided in a certain number of branch circuits, several places), and the total current flowing through the load circuit is measured by the current monitoring means 306a, and the circuit that actually consumes current when performing the interruption control. You may comprise so that interruption | blocking control may be performed. According to such a configuration, the remote control breaker is used only for the branch circuit that performs the shut-off / return control, while the normal branch switch that does not have the shut-off / return control function by the external signal is used for the other branch circuits. In combination with a reduction in the number of current monitoring means 306a used, it is difficult to increase the cost, and the distributed power supply device continuously distributes to the consumer side according to the amount of power generation that changes over time. A distributed power supply system that can supply power from a power supply can be provided.

In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the summary of this invention.

For example, in the system connection disconnection system of the distributed power source according to the present invention, when a plurality of distributed power sources are provided (a solar power generation device, a fuel cell, a micro gas turbine, etc.), each distributed power source system is connected. It is preferable that a distributed distribution power switch is provided and connected to the bus to constitute a residential distribution board. When each of the system protection means 220 for detecting the isolated operation state of the distributed power supply is provided, the input signal lines 30 of the commercial power system power failure detection signal output from the system protection means are provided and connected to the circuit switch 40. Alternatively, a signal output centralized control device that collects commercial power system power failure detection signals output from a plurality of system protection means is provided, and the commercial power system power failure occurs from the signal output centralized control device toward the circuit switch 400. You may comprise so that a detection signal may be input.

In addition, although the electric circuit switch 400 is configured using a remote control relay, the circuit switch 400 is also configured using a remote control breaker, an electromagnetic contactor, or the like that opens and closes a contact device in response to an external control signal. Also good.

DESCRIPTION OF SYMBOLS 1 System connection disconnection system 100 of distributed power supply Commercial power supply system 110 Transfer interruption signal receiver 111 Signal receiving means 200 Distributed power supply system 201 Power conversion means 210 Inverter device 220 System protection means 230 Power generation possible power calculation means 300 Load circuit 301 Main Switch 302 Branch Switch 303 Bus 304 Distributed Power System Switch 305 Load Circuit Controller 306 Current Detection Unit 307 Branch Switch 400 Electric Circuit Switch 500 Residential Distribution Board 600 Current Limiter

Claims (4)

The power supply to the load circuit
A system connection disconnection system of a distributed power source performed from both a commercial power system and a distributed power system that is connected to the commercial power system,
The system connection disconnection system of the distributed power source is
An electric circuit switch interposed in the electric circuit from the commercial power system to the load circuit, and interconnecting or disconnecting the load circuit and the distributed power system from the commercial power system;
Detected that the power supply from the commercial power system has been cut off or that the power supply from the commercial power system has been restored, provided in the system connection disconnection system of the distributed power source,
When it is detected that the power supply from the commercial power system has been interrupted, a commercial power system power failure detection signal is output to the circuit switch,
When it is detected that the power supply from the commercial power system is restored, system protection means for outputting a commercial power system restoration detection signal to the circuit switch,
The electric circuit switch that has received the commercial power system power failure detection signal output from the system protection means opens the contact of the electrical circuit switch using the commercial power system power failure detection signal as a trigger signal,
While the load circuit and the distributed power system are both disconnected from the commercial power system,
The electric circuit switch that has received the commercial power system restoration detection signal causes the commercial circuit switch restoration detection signal to be used as a trigger signal to turn on the contacts of the electric circuit switch,
Both the load circuit and the distributed power system are linked to a commercial power system,
Distributing the power supply to the load circuit by maintaining power supply to the load circuit by continuously performing power supply to the load circuit from a single distributed power supply or from both a commercial power supply and a distributed power supply. system.
The system connection disconnection system of the distributed power source is
Provided in the electric power system on the electric utility side supplying the commercial power supply,
Detecting that the power supply in the power system has stopped or that the power supply has been restored,
In response to a transfer cut-off signal or a recovery signal output from a transfer cut-off restoration signal transmitter provided in a commercial power supply system that outputs a cut-off signal for stopping power supply or a restoration signal for restoration toward another power system,
A transfer interruption signal restoration signal receiving device for outputting the commercial power system power failure detection signal or the commercial power system restoration detection signal to the electric circuit switch;
A trigger signal that drives an electric circuit switch that links or disconnects both the load circuit and the distributed power system from the commercial power system,
Instead of the commercial power system power failure detection signal or the commercial power system recovery detection signal output from the system protection means provided in the distributed power system,
Configured using the commercial power system power failure detection signal or the commercial power system recovery detection signal output from the transfer cutoff signal recovery signal receiver,
The circuit switch that has received the commercial power system power failure detection signal or the commercial power system recovery detection signal output from the transfer interruption signal recovery signal receiving device,
Using the commercial power system power failure detection signal or the commercial power system recovery detection signal as a trigger signal, the contact of the circuit switch is opened or closed,
2. The distributed power system interconnection system according to claim 1, wherein both the load circuit and the distributed power system are disconnected from or connected to a commercial power system.
While arranging the electric circuit switch according to claim 1 or claim 2 in the vicinity of the wire lead-in part,
On the load side of the circuit switch,
A main switch connected to the circuit switch;
A bus connected to the load side of the main switch;
A plurality of branch switches for branching power from the bus to each load circuit;
A switch for a distributed power system connected to the bus;
Comprising a residential distribution board with
3. The dispersion according to claim 1, wherein when the electric circuit switch is operated, all secondary circuits including the main switch are disconnected from or connected to a commercial power supply system. Type system power system disconnection system.
The system connection disconnection system of the distributed power source is
Further, a power generating power calculating means for calculating power that can be generated by the distributed power system,
Current monitoring means for measuring the current flowing through the branch circuit through the distributed power system switch; and current monitoring means for measuring the current flowing through each branch circuit;
The power consumption value in the load circuit at that time is calculated from the current value obtained from the current monitoring means, and compared with the power generation possible power value obtained by the power generation possible power calculation means, and can be used for the power generation possible power value. The power value is obtained, the ratio of the usable power value to the power generation possible power value is calculated, and when the ratio falls below a predetermined ratio, a signal for shutting off the branch circuit is output, and the power consumption in the branch circuit A load circuit controller that performs control to reduce
Whenever a load circuit and a distributed power system are disconnected from the commercial power system,
4. The system connection of the distributed power source according to claim 3, wherein the power consumption in the load circuit is controlled so that the power generation possible value in the distributed power system has a margin with respect to the power consumption value in the load circuit. system.

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