A Three-phase Synchronous Frame Controller for Uinbalanced Load

A new control scheme for 3-phase inverters is presented in this paper. This control scheme is able to completely compensate for the effect of load imbalance. The controller consists of two PI controllers in two reference frames rotating in the opposite directions. These two reference frames extract both positive and negative sequence components of the output voltage. The controller for the negative sequence components effectively compensates for the effect of load imbalance. Both simulation and experimental results are included.