Improvement method of voltage unbalance by the use of an inverter installed in distributed generations

摘要

This paper described that the improvement method of voltage and current unbalance by using distributed generators (DGs). Generaly DGs in the high voltage distribution power system are connected three phases. However, some DGs, ex photovoltaic and fuel cells etc, in the low-pressure distribution power system are connected to single phase and are connected through inverter. If the DG are connected to a distribution power system, it is possible that unbalancing of current caused by the electric power unbalance between three phases. Electric power unbalance may cause mis-operation of various apparatus assumed in use of three phase equilibriums operation, the rise in heat of an induction generator, shortening of a life span and the lower of output torque. We propose an improvement method of voltage and current unbalance caused by un-balancing of each phase load between three phases by the use of an inverter installed in DGs.