System and method for controlling power system

• US 9,774,216 B2
• Filed: 07/10/2012
• Issued: 09/26/2017
• Est. Priority Date: 07/10/2012
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Yamane, Kenichiro, Tsunedomi, Kunihiko, Uchiyama, Noriyuki, Tomita, Yasushi, Onishi, Tsukasa, Kumagai, Masatoshi
• Primary Examiner(s): Barnes-Bullock, Crystal J
• Application Number:
  US14/402,366
• Publication Number:
  US 20150142187A1
• Time in Patent Office: 1,904 Days
• CPC Class Codes: G05B 13/04 involving the use of models or simulators
• CPC Class Codes: G05B 15/02 electric
• CPC Class Codes: G05F 1/66 Regulating electric power
• CPC Class Codes: G06Q 10/04 Forecasting or optimisation specially adapted for administrative or management purposes, e.g. linear programming or "cutting stock problem" market predictions or forecasting for commercial activities G06Q30/0202
• CPC Class Codes: G06Q 50/06 Energy or water supply
• CPC Class Codes: H02J 13/00006 characterised by information or instructions transport means between the monitoring, controlling or managing units and monitored, controlled or operated power network element or electrical equipment
• CPC Class Codes: H02J 13/00007 using the power network as support for the transmission
• CPC Class Codes: H02J 13/00034 the elements or equipment being or involving an electric power substation
• CPC Class Codes: H02J 3/12 for adjusting voltage in ac networks by changing a characteristic of the network load
• CPC Class Codes: H02J 3/18 Arrangements for adjusting, eliminating or compensating reactive power in networks for adjustment of voltage H02J3/16
• CPC Class Codes: H02J 4/00 Circuit arrangements for mains or distribution networks not specified as ac or dc
• CPC Class Codes: Y02E 40/30 Reactive power compensation
• CPC Class Codes: Y02E 40/70 Smart grids as climate change mitigation technology in the energy generation sector
• CPC Class Codes: Y02E 60/00 Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y04S 10/22 Flexible AC transmission systems [FACTS] or power factor or reactive power compensating or correcting units
• CPC Class Codes: Y04S 10/30 State monitoring, e.g. fault, temperature monitoring, insulator monitoring, corona discharge
• CPC Class Codes: Y04S 40/12 characterised by data transport means between the monitoring, controlling or managing units and monitored, controlled or operated electrical equipment
• CPC Class Codes: Y04S 40/121 using the power network as support for the transmission

Abstract

To control a power state of a power system properly according to a communication state. A system for controlling a power system includes a plurality of sensor devices configured to output measurement data; a first control apparatus configured to estimate a first power state of the power system by using the measurement data obtained by the plurality of sensor devices, calculate a first controlled variable according to the estimated first power state, and output the calculated first controlled variable; and at least a second control apparatus configured to execute a predetermined control operation according to either the first controlled variable calculated in the first control apparatus, or a second controlled apparatus calculated in the second control apparatus. When it is not able to obtain part of the measurement data, the first control apparatus estimates the first power state by using predetermined measurement data among the obtained measurement data.

Claims

1. A system for controlling a power system configured to control a power state of the power system, comprising:

a plurality of sensor devices arranged in the power system and configured to output measurement data;

a first control apparatus configured to estimate a first power state of the power system by using the measurement data obtained by the plurality of sensor devices, calculate a first controlled variable according to the estimated first power state, and output the calculated first controlled variable; and

at least a second control apparatus arranged in the power system in a communicable manner with the first control apparatus and configured to execute a predetermined control operation according to either the first controlled variable calculated by the first control apparatus or a second controlled variable calculated in the second control apparatus,

wherein the first control apparatus estimates the first power state by using predetermined measurement data among the obtained measurement data when it is unable to obtain part of the measurement data,

wherein the first control apparatus is further configured to;

previously create a first power state estimating model for each combination of the predetermined measurement data to estimate the first power state according to the predetermined measurement data,

estimate the first power state by using the predetermined measurement data and the first power state estimating model that matches the combination of the predetermined measurement data that has been actually obtained among the plurality of first power state estimating models,

create a first controlled variable calculating model to calculate the first controlled variable corresponding to the estimated first power state,

calculate the first controlled variable according to the estimated first power state and the first controlled variable calculating model, and

transmit the calculated first controlled variable to the second control apparatus, and

transmit, to the second control apparatus, a second power state estimating model created from the first power state estimating model and a second controlled variable calculating model created from the first controlled variable calculating model,

wherein the second control apparatus is further configured to;

store the second power state estimating model and the second controlled variable estimating model received from the first control apparatus,

execute a first control mode in a predetermined first case, and

in the first control mode, execute the predetermined control operation according to the first controlled variable received from the first control apparatus,

execute a second control mode in a predetermined second case,

in the second control mode, estimate a second power state of the power system according to the measurement data of a predetermined sensor device among the sensor devices and the second power state estimating model,

calculate the second controlled variable according to the estimated second power state and the second controlled variable calculating model, and

execute the predetermined control operation according to the calculated second controlled variable, and

wherein the predetermined second case represents a case where it is determined that a communication state between the first control apparatus and the second control apparatus is decreased at or lower than a preset predetermined value.

2. The system for controlling a power system according to claim 1,

wherein the first control apparatus is further configured to:

store the measurement data correlated to the first controlled variable,

generate a parameter to define the second power state estimating model and the second controlled variable calculating model by using the stored measurement data and the first controlled variable as teacher data, and

transmit, to the second control apparatus, the generated parameter as the second power state estimating model and the second controlled variable calculating model.

3. The system for controlling a power system according to claim 1,

wherein the second control apparatus is further configured to:

execute a third control mode in a predetermined third case,

in the third control mode, calculate the second controlled variable according to the measurement data from the sensor device of the second control apparatus among the sensor devices and system data representing the structure of the power system, and

execute the predetermined control operation according to the calculated second controlled variable.

4. The system for controlling a power system according to claim 3,

wherein the predetermined third case represents a case where a valid period preset in the second power state estimating model is passed.

5. The system for controlling a power system according to claim 4,

wherein the valid period is set in the second power state estimating model corresponding to timing at which a power supply-demand state is changed.

6. The system for controlling a power system according to claim 1, wherein

a controlled variable of third control apparatus, which is not under control of the first control apparatus, is predicted,

the first controlled variable is calculated by using the prediction result,

the first power state is re-estimated by using the calculated first controlled variable, and

the first controlled variable is re-calculated according to the re-estimated power state.

7. A method for controlling a power state of a power system, wherein

the power system comprises:

a plurality of sensor devices configured to output measurement data;

a first control apparatus; and

at least a second control apparatus arranged in the power system in a communicable manner with the first control apparatus,

the method comprising;

estimating, by the first control apparatus, a first power state of the power system by using the measurement data obtained from the plurality of sensor devices;

calculating, by the first control apparatus, a first controlled variable according to the estimated first power state;

outputting, by the first control apparatus, the calculated first controlled variable;

executing, by the second control apparatus, a predetermined control operation according to either the first controlled variable calculated in the first control apparatus or a second controlled variable calculated in the second control apparatus;

estimating, by the first control apparatus, the first power state by using predetermined measurement data among the obtained measurement data, when it is unable to obtain part of the measurement data,

previously creating, by the first control apparatus, a first power state estimating model for each combination of the predetermined measurement data to estimate the first power state according to the predetermined measurement data;

estimating, by the first control apparatus, the first power state by using the predetermined measurement data and the first power state estimating model that matches the combination of the predetermined measurement data that has been actually obtained among the plurality of first power state estimating models;

calculating, by the first control apparatus, the first controlled variable according to the estimated first power state and the first controlled variable calculating model for calculating the first controlled variable according to the estimated first power state;

transmitting, by the first control apparatus, the calculated first controlled variable to the second control apparatus;

executing, by the second control apparatus, a first control mode when a difference between the latest data receiving time when the data is received from the first control apparatus and the last data receiving time is smaller than a predetermined first time period,

wherein in the first control mode, executing the predetermined control operation according to the first controlled variable received from the first control apparatus.

8. The method for controlling a power system according to claim 7,

wherein the first control apparatus executes steps of:

transmitting to the second control apparatus, a second power state estimating model created from the first power state estimating model and a second controlled variable calculating model created from the first controlled variable calculating model,

wherein the second control apparatus executes steps of;

storing the second power state estimating model and the second controlled variable calculating model received from the first control apparatus;

executing a second control mode when the difference between the latest data receiving time and the last data receiving time is at or longer than the predetermined first time period;

in the second control mode, estimating the second power state of the power system according to the measurement data of the predetermined sensor device among the sensor devices and the second power state estimating model;

calculating the second controlled variable according to the estimated second power state and the second controlled variable calculating model; and

executing the predetermined control operation according to the calculated second controlled variable.