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Title: Active Power Control of Wind Turbines for Ancillary Services: A Comparison of Pitch and Torque Control Methodologies

Abstract

As wind energy generation becomes more prevalent in some regions, there is increased demand for wind power plants to provide ancillary services, which are essential for grid reliability. This paper compares two different wind turbine control methodologies to provide active power control (APC) ancillary services, which include derating or curtailing power generation, providing automatic generation control (AGC), and providing primary frequency control (PFC). The torque APC controller provides all power control through the power electronics whereas the pitch APC controller uses the blade pitch actuators as the primary means of power control. These controllers are simulated under various wind conditions with different derating set points and AGC participation levels. The metrics used to compare their performance are the damage equivalent loads (DELs) induced on the structural components and AGC performance metrics, which are used to determine the payments for AGC services by system operators in the United States. The simulation results show that derating the turbine reduces structural loads for both control methods, with the APC pitch control providing larger reductions in DELs, lower AGC performance scores, and higher root-mean-square pitch rates. Providing AGC increases the structural loads when compared to only derating the turbine, but even the AGC DELsmore » are generally lower than those of the baseline control system. The torque APC control methodology also allows for more sustained PFC responses under certain derating conditions.« less

Authors:
; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Wind and Water Technologies Office (EE-4W)
OSTI Identifier:
1320389
Report Number(s):
NREL/CP-5000-66074
DOE Contract Number:
AC36-08GO28308
Resource Type:
Conference
Resource Relation:
Conference: Presented at the 2016 American Control Conference (ACC), 6-8 July 2016, Boston, Massachusetts
Country of Publication:
United States
Language:
English
Subject:
17 WIND ENERGY; 24 POWER TRANSMISSION AND DISTRIBUTION; ancillary services; wind power; active power control; damage equivalent loads; torque APC; pitch APC

Citation Formats

Aho, Jacob, Fleming, Paul, and Pao, Lucy Y. Active Power Control of Wind Turbines for Ancillary Services: A Comparison of Pitch and Torque Control Methodologies. United States: N. p., 2016. Web. doi:10.1109/ACC.2016.7525114.
Aho, Jacob, Fleming, Paul, & Pao, Lucy Y. Active Power Control of Wind Turbines for Ancillary Services: A Comparison of Pitch and Torque Control Methodologies. United States. doi:10.1109/ACC.2016.7525114.
Aho, Jacob, Fleming, Paul, and Pao, Lucy Y. 2016. "Active Power Control of Wind Turbines for Ancillary Services: A Comparison of Pitch and Torque Control Methodologies". United States. doi:10.1109/ACC.2016.7525114.
@article{osti_1320389,
title = {Active Power Control of Wind Turbines for Ancillary Services: A Comparison of Pitch and Torque Control Methodologies},
author = {Aho, Jacob and Fleming, Paul and Pao, Lucy Y.},
abstractNote = {As wind energy generation becomes more prevalent in some regions, there is increased demand for wind power plants to provide ancillary services, which are essential for grid reliability. This paper compares two different wind turbine control methodologies to provide active power control (APC) ancillary services, which include derating or curtailing power generation, providing automatic generation control (AGC), and providing primary frequency control (PFC). The torque APC controller provides all power control through the power electronics whereas the pitch APC controller uses the blade pitch actuators as the primary means of power control. These controllers are simulated under various wind conditions with different derating set points and AGC participation levels. The metrics used to compare their performance are the damage equivalent loads (DELs) induced on the structural components and AGC performance metrics, which are used to determine the payments for AGC services by system operators in the United States. The simulation results show that derating the turbine reduces structural loads for both control methods, with the APC pitch control providing larger reductions in DELs, lower AGC performance scores, and higher root-mean-square pitch rates. Providing AGC increases the structural loads when compared to only derating the turbine, but even the AGC DELs are generally lower than those of the baseline control system. The torque APC control methodology also allows for more sustained PFC responses under certain derating conditions.},
doi = {10.1109/ACC.2016.7525114},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2016,
month = 8
}

Conference:
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