Power system voltage stabilizer and stabilization method

Patent metadata

Field	Value
Publication number	US-9537314-B2
Application number	US-201114240100-A
Country	US
Kind code	B2
Filing date	Sep 2, 2011
Priority date	Sep 2, 2011
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

In an electric power system with a distributed power source, a fluctuation of its system voltage is brought about by an amount of power generation of the distributed power source that depends on weather. Stabilization of the system voltage is realized by generating a driving signal of a switch that the system has from weather forecast information and power system information and switching a configuration of the system.

First claim

The invention claimed is:

1. A power system comprising:
a plurality of nodes;
a plurality of natural energy power generation apparatuses;
a plurality of switches disposed at respective nodes connecting respective natural energy power generation apparatuses to the power system;
a plurality of voltage control apparatuses respectively disposed at one or more of the plurality of nodes, wherein each voltage control apparatus is one of a step voltage control apparatus and a static var compensator,
a voltage stabilizer for stabilizing a voltage of the power system, wherein the voltage stabilizer comprises:
a power generation quantity predilection part configured to receive weather forecast information;
a voltage apparatus signal generation part connected to the power generation quantity part and connected to the plurality of voltage control apparatuses; and
a system reconfiguration signal generation part connected to the voltage apparatus signal generation part and each of the plurality of switches, the system reconfiguration signal generation part configured to receive system configuration information,
wherein the power generation quantity prediction part is configured to predict an amount of power generation of the respective natural energy power generation apparatuses based on the received weather forecast information,
wherein the voltage control apparatus signal generation part is configured to generate control signals for controlling the plurality of voltage control apparatuses based on the predicted amount of power generation of the natural energy power generation apparatuses,
wherein the system reconfiguration signal generation part is configured to calculate an open/close instruction for connecting/disconnecting each of the switches of the power system based on the predicted amount of power generation of the plurality the respective natural energy power generation apparatuses and the system configuration information, and generate a driving signal for each of the plurality of switches based on the open/close instruction for the switches, and
wherein the system configuration information includes node location information of each of the voltage control apparatuses, location information of each of the switches, and location information of each of the natural energy power generation apparatuses.

2. The power system according to claim 1 ,
wherein the natural energy power generation apparatus is one of solar photovoltaic generation and wind power generation.

3. The power system according to claim 1 ,
wherein the weather forecast information includes an amount of solar radiation in an electric power system having solar photovoltaic generation, and a wind speed in an electric power system having wind power generation.

4. The power system according to claim 1 ,
wherein the system configuration information includes a connection point of a distributed power source, a line of the system, and a kind of a voltage control apparatus.

5. The power system according to claim 1 ,
wherein the driving signal of the switch is generated so that the system may go through a plurality of stages of system configurations that span from a system configuration at the present moment to a system configuration that is reconfigured.

6. A system voltage stabilization method for stabilizing a voltage of a power system, the power system comprising:
a plurality of nodes;
a plurality of natural energy power generation apparatuses;
a plurality of switches disposed at respective nodes connecting respective natural energy power generation apparatuses to the power system;
a plurality of voltage control apparatuses respectively disposed at one or more of the plurality of nodes, wherein each voltage control apparatus is one of a step voltage control apparatus and a static var compensator,
a voltage stabilizer for stabilizing a voltage of the power system, wherein the voltage stabilizer comprises:
a power generation quantity predilection part;
a voltage apparatus signal generation part connected to the power generation quantity part and connected to the plurality of voltage control apparatuses; and
a system reconfiguration signal generation part connected to the voltage apparatus signal generation part and each of the plurality of switches,
the method comprising the steps of:
receiving weather forecast information, by the power generation quantity prediction part;
receiving system configuration information of the power system, by the system reconfiguration signal generation part;
predicting an amount of power generation of the natural energy power generation apparatuses based on the weather forecast information, by the power generation quantity part;
generating control signals for controlling the voltage control apparatuses based on the predicted amount of power generation of the natural energy power generation apparatuses, by the voltage control apparatus signal generation part; and
calculating an open/close instruction for connecting/disconnecting each switch of the power system based on the predicted amount of power generation of the natural energy power generation apparatuses and the system configuration, and generating a driving signal for each of the switches based on the open/close instruction for the switches, by the system reconfiguration signal generation part,
wherein the system configuration information includes node location information of each of the voltage control apparatuses, location information of each of the switches, and location information of each of the natural energy power generation apparatuses.

7. The power system electric power stabilizer according to claim 1 ,
wherein the open/close instruction is calculated so that a system voltage of the power system is maintained within a predetermined range.

8. The power system electric power stabilizer according to claim 1 ,
wherein the open/close instruction is calculated so that a deviation of a system voltage of the power system is minimized.

9. The power system voltage stabilization method according to claim 6 ,
wherein the open/close instruction is calculated so that a system voltage of the power system is maintained within a predetermined range.

10. The power system voltage stabilization method according to claim 6 ,
wherein the open/close instruction is calculated so that a deviation of a system voltage of the power system is minimized.

Assignees

• Inuzuka Tatsuki
• Kobayashi Hideyuki
• Hitachi Ltd

Inventors

• Inuzuka Tatsuki
• Kobayashi Hideyuki

Classifications

• H02J3/003 Primary

  Load forecast, e.g. methods or systems for forecasting future load demand · CPC title

• H02J3/381

  Dispersed generators · CPC title

• H02J2101/28

  Wind energy · CPC title

• H02J2101/24

  Photovoltaics · CPC title

• H02J2101/20

  Dispersed power generation using renewable energy sources · CPC title