Control of a Four-Leg Converter for the Operation of a DFIG Feeding Stand-Alone Unbalanced Loads

This paper presents a topology for a three-phase generation system for an isolated unbalanced load fed by a doubly fed induction generator with a neutral wire to include single-phase loads. The challenges of unbalanced loads connected to the system are presented along with a proposal for mitigating current imbalance by employing a four-leg rectifier. The proposed compensation method is based on the sequence decomposition analysis, and thus, it is based on previous works that use current control in double synchronous reference frames. Nevertheless, a conceptual analysis is presented that vindicates the use of resonant controllers in the stationary abc frame.