System and method for automatic generation control in wind farms

• US 9,915,243 B2
• Filed: 02/18/2015
• Issued: 03/13/2018
• Est. Priority Date: 02/24/2014
• Status: Active Grant

• Current Assignee: GE Infrastructure Technology, LLC (GE Vernova, Inc.)
• Original Assignee: General Electric Company
• Inventors: Sagi, Deepak Raj, Cardinal, Mark Edward, Saha, Avijit, Burra, Rajni Kant, Ganireddy, Govardhan
• Primary Examiner(s): Partridge, William B
• Assistant Examiner(s): Ahmed, Istiaque
• Application Number:
  US14/625,108
• Publication Number:
  US 20150240784A1
• Time in Patent Office: 1,119 Days
• Field of Search: None
• CPC Class Codes: F03D 7/0284 in relation to the state of the electric grid
• CPC Class Codes: F03D 7/048 controlling wind farms
• CPC Class Codes: F03D 9/10 Combinations of wind motors with apparatus storing energy
• CPC Class Codes: F03D 9/11 storing electrical energy
• CPC Class Codes: F03D 9/257 the wind motor being part of a wind farm
• CPC Class Codes: F05B 2260/82 Forecasts
• CPC Class Codes: F05B 2270/335 Output power or torque
• CPC Class Codes: F05B 2270/404 active, predictive, or anticipative
• CPC Class Codes: G05B 15/02 electric
• CPC Class Codes: G05B 2219/2619 Wind turbines
• CPC Class Codes: H02J 2300/28 The renewable source being wind energy
• CPC Class Codes: H02J 3/32 using batteries with converting means
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction
• CPC Class Codes: Y02E 10/76 Power conversion electric or electronic aspects
• CPC Class Codes: Y02E 70/30 Systems combining energy storage with energy generation of non-fossil origin

Abstract

A system for automatic generation control in a wind farm is provided. The system includes a wind farm controller for controlling the plurality of energy storage elements. The wind farm controller receives an automatic generation control set point from an independent system operator, generates a farm-level storage power set point for the wind farm based on the automatic generation control set point, generates individual storage power set points for the plurality of energy storage elements based on states of charge of the respective energy storage elements, and controls the plurality of energy storage elements based on the individual storage power set points for dispatching storage power to perform automatic generation control.

Claims

1. A method for automatic generation control in a wind farm comprising:

receiving an automatic generation control set point from an independent system operator;

generating a farm-level storage power set point for the wind farm based on the automatic generation control set point using a wind farm controller;

generating individual storage power set points for a plurality of energy storage elements using the wind farm controller, wherein each of the plurality of energy storage elements is coupled to a corresponding wind turbine of a plurality of wind turbines, and wherein the individual storage power set points are generated based on states of charge of respective energy storage elements; and

controlling the plurality of energy storage elements based on the individual storage power set points for dispatching storage power to perform automatic generation control based on an aggressive optimal dispatch method, wherein dispatching the storage power based on the aggressive optimal dispatch method comprises prioritizing a storage power dispatch from the plurality of energy storage elements based on charging coefficients and discharging coefficients in a descending order, wherein the charging coefficients are represented as;

2. The method of claim 1, further comprising, prior to receiving the automatic generation control set point, generating a farm-level base point power forecast for the wind farm.

3. The method of claim 2, wherein generating the farm-level base point power forecast comprises generating a farm-level aero power forecast and a farm-level forecast adjustment.

4. The method of claim 3, wherein generating the farm-level aero power forecast comprises adding a plurality of turbine-level aero power forecasts received from a plurality of wind turbine controllers of respective wind turbines and generating the farm-level forecast adjustment comprises computing an average state of charge of the plurality of energy storage elements.

5. The method of claim 1, wherein generating the individual storage power set points based on the states of charge of the respective energy storage elements further comprises balancing the states of charge of the plurality of energy storage elements.

6. The method of claim 5, wherein balancing the states of charge of the plurality of energy storage elements comprises equalizing the states of charge of the plurality of energy storage elements.

7. The method of claim 1, wherein the charging coefficients and discharging coefficients are determined based on a state of charge corresponding to each of the plurality of energy storage elements.

8. The method of claim 1, wherein the discharging coefficients are represented as

9. A system for automatic generation control in a wind farm comprising:

a plurality of wind turbines;

a plurality of energy storage elements, wherein each of the plurality of energy storage elements is integrated within or coupled to a corresponding wind turbine of the plurality of wind turbines;

a wind farm controller for controlling the plurality of energy storage elements, wherein the wind farm controller is configured for executing the steps of;

receiving an automatic generation control set point from an independent system operator;

generating a farm-level storage power set point for the wind farm based on the automatic generation control set point;

generating individual storage power set points for the plurality of energy storage elements based on states of charge of respective energy storage elements; and

controlling the plurality of energy storage elements based on the individual storage power set points for dispatching storage power to perform automatic generation control based on an aggressive optimal dispatch method, wherein dispatching the storage power based on the aggressive optimal dispatch method comprises prioritizing a storage power dispatch from the plurality of energy storage elements based on charging coefficients and discharging coefficients in a descending order, wherein the charging coefficients are represented as;

10. The system of claim 9, further comprising wind turbine controllers for generating a plurality of turbine-level aero power forecasts for the plurality of wind turbines.

11. The system of claim 9, wherein the farm-level storage power set point is further generated based on a wind farm error.

12. The system of claim 11, wherein the wind farm controller computes a wind farm error based on the farm-level base point power forecast and a measured base point power.

13. The system of claim 9, wherein the individual storage power set points are generated to balance the states of charge of the plurality of energy storage elements.

14. The system of claim 9, wherein automatic generation control set point comprises a grid frequency control set point and a tie-line power set point.

15. The system of claim 9, wherein the charging coefficients and discharging coefficients are determined based on a state of charge corresponding to each of the plurality of energy storage elements.

16. The system of claim 9, wherein the discharging coefficients are represented as