Performance analysis of synchronization methods for self-excited induction generators

This paper analyzes sensorless digital control systems used to regulate the output voltages of a self-excited squirrel-cage induction generator. Different mechanical sensorless synchronization methods are evaluated and their performances are compared under several load conditions, including unbalanced and nonlinear loads. The effect of frequency variations on the performance of the synchronization methods is also investigated. Simulation and experimental results are included to demonstrate the impact of distinct digital control systems on the output voltages distortion and unbalance.