Speed sensorless control for brushless doubly-fed generator based on fuzzy logic

For the brushless doubly-fed wind power generator with special structure, a suitable direct torque control strategy based on speed sensorless technology is proposed. The speed of brushless doubly-fed generator (BDFG) is obtained by estimating the synchronous rotating speed of the rotor flux and the slip speed to implement the speed sensorless control. Due to the accuracy of estimating the slip speed suffering from the influence of the load changing, the fuzzy logic is introduced to enable the system robustness. The simulation study is carried out by Matlab/ Simulink software to verify the validity of the proposed speed estimation method, and the BDFG speed estimating accuracy of the speed sensorless control system without or with fuzzy logic is compared and analyzed.