Frequency Regulation and Operating Reserve Techniques for Variable Speed Wind Turbines
James Boyle, Tim Littler, Aoife Foley
Abstract
This paper proposes a control scheme for variable speed wind turbines that provides both operating reserve and frequency-droop regulation via rotor speed control. The control scheme is compared to conventional rotor speed control and pitch angle frequency-droop control techniques. Simulation results performed using the IEEE 39-bus power system model in DIgSILENT PowerFactory show that the proposed scheme produces fast-acting, accurate frequency-droop responses to grid imbalances. The speed of response improves the frequency nadir resulting from simulated frequency contingencies. The proposed control scheme can be used as a substitute, or supplement, to reserve and frequency regulation schemes that operate via pitch angle control.