Controlling system for parallel operation of AC output inverters with restrained cross currents

摘要

Disclosed is a parallel power supply system including AC output inverters for controlling instantaneous values of output voltages by causing arms of respective inverters of the AC output inverters to effect switching in respective phases of the output voltages plural times during one cycle. A bus for connecting outputs on the inverters to a load so that a load current is shared by the inverters. A synchronous circuit for synchronizing the respective inverters by outputting common synchronous signals to the inverters. A detection circuit for detecting a cross current component of an electric current flowing between the respective inverters, and a control circuit for controlling the output voltages of the inverters to restrain the cross current component detected by the detection circuit.