Fast Inertial Response of PMSG-Based Wind Turbines With Optimized Frequency-Locked Loop
Le Li, Donghai Zhu, Jiabing Hu, Lei Lin, Xudong Zou, Yong Kang
Abstract
This letter proposes an optimized frequency-locked loop (FLL) for the permanent magnet synchronous generator-based wind turbines to achieve fast inertial response. First, the principle of inertial response is analyzed, finding that changing the FLL output phase can realize inertial response. Then, the optimized FLL is proposed by integrating the estimated angular frequency error and its derivative into the output phase, which enables an instantaneous inertial response. Compared with the classical <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">df/dt</i> inertia control, the proposed optimized FLL reacts to frequency changes faster, and better rate of change of frequency and frequency nadir are obtained. Finally, the proposed method is validated by experiments.