Performance of induction generator in parallel with an unbalanced three phase system

Induction generators driven by wind and hydro power are ideal energy sources for wind farms and low cost hydroelectric plants. To improve the overall installation efficiency, most induction generators are integrated to 33 kV or lower voltage electric utility distribution systems. It is not practical that such systems are three-phase balanced because of unbalanced load and feeder impedance. This paper addresses the features of induction machines which are connected to an unbalanced power distribution system. The study also investigates the impact of unbalanced supply sources embedded with induction generators on distribution network protective relay operation.