Sensorless control of wind power generator with flywheel energy storage system

For the purpose of sensorless low-speed control of direct-drive permanent magnet synchronous generator–based wind power systems, a technique based on the rotating high-frequency voltage-signal injection is discussed in this article, which improves the efficiency of the method and eliminates the phase shift introduced by traditional filters; band pass and low-pass filters are replaced by an extended complex Kalman filter algorithm. In addition, a flywheel energy storage system based on a squirrel cage induction machine is connected with the wind power generator by a DC bus through two power converters. For sensorless control of the induction machine, a rotor speed estimation method based on the extended complex Kalman filter is established. Finally, network connection interface of the complete system is presented and the efficiency of the proposed sensorless control of the whole chain of wind power generation is shown by numerical simulations using MATLAB/Simulink environment.