Grid-forming wind turbine based on novel wind-speed-measurement-free deloading control

Traditional wind turbine deloading relies on wind speed measurement, which is often inaccurate due to sensor limitations, affecting deloading precision. This study first addresses the challenge of reference power assignment in the constant-speed region by proposing an additional power control strategy based on adaptive reference power assignment via rotor speed feedback, eliminating power fluctuations and enhancing wind energy utilization. Secondly, a novel wind-speed-measurement-free deloading method is introduced: at low wind speeds, deloading is achieved by adjusting the optimal power coefficient; at medium and high wind speeds, a unique mapping between additional deloading power and pitch angle in the constant-speed region is established and fitted into a function using least squares. By measuring additional power and inputting it into the fitted curve, the corresponding pitch angle reference is obtained without wind speed measurement. In the power-limit region, smooth pitch angle transition is achieved, constraining power to a specified value. Grid-forming control with matching control is adopted to mitigate DC voltage fluctuations.