Research on the Unbalanced Load for Brushless Doubly Fed Induction Generation System on Predictive Current Control

Brushless doubly-fed induction generator (BDFIG) shows broad application prospects in grid-connected mode and stand-alone mode due to the high reliability and low maintenance costs. The unbalanced load faults always occur when the BDFIG operated in stand-alone mode, which lead the unbalanced of the output voltage, and thus the non-faulty loads are affected, reducing the system reliability. In order to ensure non-faulty loads normal supplied when the unbalance load faults occur, this paper presents the predictive current control (PCC) strategy for BDFIG system. First, the synchronous rotating reference frame dq is adopted to obtain the positive and negative reference components; Second, the proposed PCC strategy is analyzed and designed in detail. At last, the experiments show that the control strategy has fast response under normal operation, and the non-faulty loads can achieve balanced voltage supply when the unbalanced load faults. The experiments results verify the proposed control method can improve the reliability of the system significantly