*Article* **Adaptive Pitch Control of Variable-Pitch PMSG Based Wind Turbine**

### **Jian Chen 1, Bo Yang 2,\*, Wenyong Duan 1, Hongchun Shu 2, Na An 2, Libing Chen 1 and Tao Yu 3**


Received: 29 August 2019; Accepted: 24 September 2019; Published: 1 October 2019

**Abstract:** This paper presents an adaptive pitch-angle control approach for a permanent magnet-synchronous generator-based wind turbine (PMSG-WT) connecting with a power grid to limit extracted power above the rated wind speed. In the proposed control approach, a designed perturbation observer is employed for estimating and compensating unknown parameter uncertainties, system nonlinearities, and unknown disturbances. The proposed control approach does not require full state measurements or the accurate system model. Simulation tests verify the effectiveness of the proposed control approach. The simulation results demonstrate that compared with the feedback linearizing controller, conventional vector controller with proportional-integral (PI) loops, and PI controller with gain scheduling, the proposed control approach can always maintain the extracted wind power around rated power, and has higher performance and robustness against disturbance and parameter uncertainties.

**Keywords:** pitch control; permanent magnet-synchronous generator (PMSG); limit extracted power; nonlinear adaptive control (NAC); perturbation observer
