Control of unbalanced three-phase power electronic systems

This paper examines the control of unbalanced three-phase three-wire power electronic systems. The definition of the control strategy for the unbalanced three-phase system is based on the equivalent two-phase unbalanced-coupled model. The control strategy proposed is derived from the double controller scheme that employs one controller for the positive sequence and another for the negative sequence. An extension of the control strategy to deal with the presence of high frequency harmonics in the system is also addressed. The controller is implemented in a microcomputer-based system at the stationary reference frame. The simulation and experimental results demonstrate the validity of the proposed methodology