METHODS AND SYSTEMS FOR CONTROLLING AN ELECTRIC NETWORK

• US 20150112496A1
• Filed: 10/17/2013
• Published: 04/23/2015
• Est. Priority Date: 10/17/2013
• Status: Active Grant

• Current Assignee: GE Infrastructure Technology, LLC (GE Vernova, Inc.)
• Original Assignee: General Electric Company
• Inventors: Fisher, Rayette Ann, Ren, Wei, Walling, Reigh Allen, Satya, Murali Mohan Baggu Datta Venkata, Viana, Felipe Antonio Chegury, Anaparthi, Krishna Kumar
• Granted Patent: US 10,135,247 B2
• Time in Patent Office: Days
• US Class Current: 700/291
• CPC Class Codes: H02J 13/00016 using a wired telecommunication network or a data transmission bus
• CPC Class Codes: H02J 13/00024 by means of mobile telephony
• CPC Class Codes: H02J 13/00028 involving the use of Internet protocols
• CPC Class Codes: H02J 13/00034 the elements or equipment being or involving an electric power substation
• CPC Class Codes: H02J 2203/20 Simulating, e g planning, reliability check, modelling or computer assisted design [CAD]
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 3/16 by adjustment of reactive power
• CPC Class Codes: H02J 3/1842 wherein at least one reactive element is actively controlled by a bridge converter, e.g. active filters
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y02B 70/3225 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers
• CPC Class Codes: Y02E 40/20 Active power filtering [APF]
• 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 10/00 Systems supporting electrical power generation, transmission or distribution
• CPC Class Codes: Y04S 10/123 the energy generation units being or involving renewable energy sources
• 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 20/221 General power management systems
• CPC Class Codes: Y04S 20/222 : Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y04S 40/124 : using wired telecommunication networks or data transmission busses
• CPC Class Codes: Y04S 40/126 : using wireless data transmission
• CPC Class Codes: Y04S 40/20 : Information technology specific aspects, e.g. CAD, simulation, modelling, system security

Abstract

A method and system for use in controlling an electric network are provided. The system includes an Integrated Volt-VAr Control (IVVC) component configured to determine optimization parameters for slow dynamics electromechanical devices and fast dynamics DER devices coupled to the network. The slow dynamics devices are controlled by a present state of the electric network and a voltage rise table that is adaptively updated in real-time using a command output, or a power flow-based complete optimization routine that generates optimal setpoints for the traditional controllable assets and for at least some of the fast dynamics DER devices. The fast dynamics devices are controlled locally using a control algorithm that uses a reactive power contribution based on IVVC settings, based on photo-voltaic (PV) plant active power variations, based on power factor, or based on a voltage of the local electric network.

Claims

1. A system for use in controlling an electric network comprising a plurality of slow dynamics electromechanical devices and a plurality of fast dynamics Distributed Energy Resource (DER) devices configured for relatively fast and continuous dynamic variation of a reactive power output, said system comprising an Integrated Volt-VAr Control (IVVC) component configured to determine one or more optimization parameters for the plurality of slow dynamics electromechanical devices and the plurality of fast dynamics DER devices, the slow dynamics devices are configured to be controlled by a present state of the electric network and at least one of a voltage rise table that is adaptively updated in real-time using at least one of a command output and a power flow-based complete optimization routine for generating optimal setpoints for the slow dynamics devices and for at least some of the fast dynamics DER devices, the fast dynamics devices are configured to be controlled locally between the remote control update using at least one of a control algorithm using a DER reactive power contribution based on IVVC settings, a control algorithm using a DER reactive power contribution based on variable generation DER active power variations, a control algorithm using a DER reactive power contribution based on power factor, and a control algorithm using a DER reactive power contribution based on a voltage of the local electric network.

2. The system of claim 1, wherein the slow dynamics electromechanical devices include at least one of a load tap changing transformer or autotransformer, a step-voltage regulator, and a switched capacitor bank.

3. The system of claim 1, wherein fast dynamics DER devices include at least one of a photovoltaic generator, a synchronous generator, a battery energy storage, a static synchronous compensator (STATCOM), a flexible AC transmission system (FACTS) device, and a static VAR compensator (SVC).

4. The system of claim 1, wherein the reactive power output of the fast acting dynamic DERs is discretized in to linear steps to include in the lookup table based approach or the power flow based optimization routine.

5. The system of claim 1, wherein the local control algorithm using a DER reactive power contribution based on IVVC settings determines a reactive power setting based directly on the variable generation DER setting provided by IVVC optimization for a next time period of a plurality of time periods.

6. The system of claim 1, wherein the control algorithm using a DER reactive power contribution based on variable generation DER active power variations determines a reactive power setting based on error in a real power estimate to be generated by the DER for a next time period of a plurality of time periods.

7. The system of claim 1, wherein the control algorithm using a DER reactive power contribution based on power factor determines a reactive power setting based on a change in a power factor estimate for the DER for a next time period of a plurality of time periods.

8. The system of claim 1, wherein the control algorithm using a DER reactive power contribution based on a voltage of the local electric network determines a reactive power setting based on an error in a voltage estimate for the DER for a next time period of a plurality of time periods.

9. A method of controlling an electric network comprising:

a). modeling the electric network to determine an expected voltage response to a first electric network state, the state relating to a first configuration of components of the electric network;

b). determining a second state of the electric network, the second state occurring a predetermined time after the first state;

c). receiving historical state data of the electric network, the historical state occurring prior to the occurrence of the first state;

d). determining a second configuration of the components of the electric network based on the model, second network state, and historical network state data;

e). transmitting commands to the components to achieve the second configuration; and

f). re-perform steps a)-e) after a predetermined time period.

10. The method of claim 9, wherein the components of the electric network include relatively fast responding components and relatively slow responding components.

11. The method of claim 10, wherein the relatively slow responding components include at least one of a load tap changer (LTC), a step voltage regulator, and a switched capacitor bank.

12. The method of claim 10, wherein the relatively fast responding components include at least one of a distributed energy resource, a distribution network flexible AC transmission system (DFACTS), an energy storage device, and a series compensator.

13. The method of claim 9, wherein transmitting commands to the components to achieve the second configuration comprises transmitting commands to relatively slow responding components at relatively long intervals.

14. The method of claim 9, wherein transmitting commands to the components to achieve the second configuration comprises transmitting commands to relatively fast responding components in approximately one hour intervals or less.

15. The method of claim 9, wherein transmitting commands to the components to achieve the second configuration comprises transmitting baseline commands to relatively fast responding components in real-time based on the local control.

16. The method of claim 9, wherein the components of the electric network include relatively fast responding components and relatively slow responding components and wherein the relatively slow responding components set a voltage level on a relatively large portion of the electric network and wherein each of the relatively fast responding components set a voltage level on a relatively small portion of the electric network.

17. An electric network control system comprising:

a network model component comprising a model of electrical components electrically coupled to form an electrical transmission and distribution network;

a measurement component configured to receive, from a plurality of sensors, data relating to measured parameters of the network and configured to determine a present state of the electric network;

a historian component configured to receive the sensor data and store at least some of the sensor data;

an estimator component configured to determine an estimate of a system load on the electric network and an estimate of generation of renewable sources coupled to the electric network using the at least some of the sensor data;

an integrated Volt-VAr control (IVVC) component configured to determine one or more optimization parameters for slow dynamics devices and fast dynamics devices coupled to the electric network, wherein the slow dynamics devices are configured to be operable at a single value of the one or more optimization parameters for a relatively long time period compared to a relatively short time period that the fast dynamics devices are operable at a single value of the one or more optimization parameters; and

a dispatch command component configured to;

receive the optimization parameters;

determine at least one of an optimal commitment for capacitor bank devices, distributed energy resource (DER) reactive power baseline values, and tap settings for voltage regulator and load tap changers (LTC), and

issue a dispatch message to the devices connected to the electric network.

18. The system of claim 17, wherein said IVVC component further comprises an adaptive closed loop voltage rise table updater configured to:

receive the issued dispatch messages and the present electric network state information; and

generate a revised voltage rise table for the electric network.

19. The system of claim 17, wherein said IVVC component further comprises an adaptive logic component configured to:

receive the issued dispatch messages and the present electric network state information; and

generate a revised voltage rise lookup table for the electric network.

20. The system of claim 17, wherein said voltage rise table updater is configured to receive present electric network state information from a Supervisory Control and Data Acquisition (SCADA) system communicatively coupled to the electric network.

21. The system of claim 17, wherein said IVVC component further comprises a local fast dynamics device controller, said fast dynamics device controller comprising at least one of a control algorithm using a DER Reactive power contribution based on IWC settings, a control algorithm using a DER Reactive power contribution based on PV plant Active Power variations, a control algorithm using a DER Reactive power contribution based on power factor, and a control algorithm using a DER Reactive power contribution based on local electric network voltage.

22. The system of claim 21, wherein at least one of said algorithms receives a current setting of the variable generation DER for reactive power contribution.