Frequency control from wind power stations with battery energy storage

Abstract

This thesis investigates control systems that enable wind power stations to provide frequency control services that can replace services that are currently provided by fossil-fuel synchronous generation. The control schemes proposed in this thesis improve existing methods currently employed in the wind generation industry, and in some cases presents new methodologies to provide enhanced control of power generation from wind power stations that incorporate battery energy storage. The wind turbine frequency control systems presented in this thesis improved the accuracy of frequency-droop action that can be achieved via rotor speed control when compared to techniques proposed in literature and those currently implemented by wind turbine manufacturers. The availability and predictability of frequency control responses from wind-battery power stations was improved by utilizing coordinated control of wind power generation and battery energy storage. One of the main limitations of battery systems is their low energy capacity. The control schemes presented throughout this thesis promote sustentation of the battery system’s nominal charge levels to mitigate energy capacity issues and to increase the self-sufficiency of wind-battery power stations. New control measures for wind power stations to enable self-regulating, dispatchable power generation will be key to delivering on Ireland and Northern Ireland’s renewable energy share in electricity goals. This thesis explored coordination schemes for wind-battery power stations to enable dispatchable generation, synthetic inertia and predictable droop action to frequency excursion events. Test case results, produced using DIgSILENT PowerFactory, demonstrated the effectiveness of the control schemes presented, and the advantages they offer over methods currently employed in industry. It is concluded that the methods proposed in this thesis can be used to improve the reliability, predictability, and efficiency of response from wind-battery systems to enable wind power stations to provide greater levels of frequency control system services to system operators.

Date of Award	Jul 2025
Original language	English
Awarding Institution	Queen's University Belfast
Sponsors	Atlantic Technological University
Supervisor	Timothy Littler (Supervisor), Xueqin Amy Liu (Supervisor) & Ahmad Elkhateb (Supervisor)