Modelling and analysis of STATCOM based voltage regulator for self-excited induction generator with unbalanced loads

This paper presents an analysis of the three-phase self-excited induction generator (SEIG) with static-compensator (STATCOM) as a voltage regulator. Current controlled voltage source inverter (CC-VSI) is used as STATCOM, which provides fast dynamic response to maintain constant voltage at SEIG terminals during severe load perturbations and acts as a source and sink of reactive power. The performance equations are derived using d-q variable in stationary reference frame to develop a mathematical model of SEIG-STATCOM system feeding unbalanced loads. Transient analysis of the SEIG-STATCOM system is carried out for voltage build-up; switching in STATCOM, application and removal of balanced/unbalanced resistive/reactive loads. The STATCOM compensates the unbalanced load and keeps the generating system balanced while maintaining constant AC terminal voltage.