Active disturbance rejection control for an unbalanced stand-alone doubly fed induction generator

In this paper, an improved control approach for the stand-alone doubly fed induction generator (DFIG) under unbalanced condition is investigated. In unbalanced case, the quality of stator voltage and current of DFIG are badly affected by the negative sequence components, and this will reduce the performance of other normal loads connected to the DFIG. To tackle this problem, a forced stator voltage-oriented vector controller based on active disturbance rejection control (ADRC) method is proposed. Besides, a proportional integral plus a resonant controller, which can simplify the controller structure, is used to regulate both the positive and negative sequence components. Filtering capacitors are employed to get high quality of generated voltage. This proposed controller has a good performance under variable speed and unbalance load conditions. Simulation results are given to illustrate the efficacy of the proposed method.