Voltage source converters in distributed generation systems

A large number of distributed generation (DG) units are being integrated into power systems at distribution level. Many of the DG units may be connected into power systems with power electronic interfaces, in particular, voltage source converters. Consequently, the operation and control modes of the voltage source converters determine the performance of the generation systems and play an essential role in affecting the security of the connected power systems. This paper discusses the operation and control of the power converter and investigates the behaviors of various types of DG units under power system fault conditions, including an induction generator, a synchronous generator and a voltage controlled voltage source converter.