A hybrid sensorless control of PMSG wind-power generator with frequency signal injection method and extended Kalman filter

Abstract

Based on the rotating high-frequency voltage-signal injection technique this paper introduces and compares two different approaches to extract the rotor position information for sensorless low speed control of direct-drive permanent magnet synchronous generator-based wind power system. One of the approaches is to extract the rotor position information from the carrier current of permanent magnet synchronous generator (PMSG) by the traditional bandpass filter. The other one is to use an extended Kalman filter algorithm. The effectiveness of the proposed sensorless low speed control is shown by numerical simulations using MATLAB/Simulink environment. The simulation results show that both control schemes provide an accurate estimate of the position of the PMSG-wind turbine and shaft speed. But extended Kalman filter algorithm improves the efficiency of the high-frequency voltage-signal injection method by eliminate the phase shift introduce by the traditional bandpass filter.