Power conversion device, ground voltage voltage estimation method, and distributed power supply system

摘要

To provide an electric power conversion system capable of narrowing down an earth position when an earth has occurred, a method of estimating voltage at an earth position, and a distributed power supply system.SOLUTION: An electric power conversion system that converts electric power by switching, comprises: a non-insulated converter; a DC bus connected to the converter; an earth detection element that is interposed between an earth position on a cable run and an intermediate node obtained by dividing a voltage of two lines of the DC bus at the time of an earth; and a control unit that controls the converter. The control unit changes a voltage of the DC bus by using the converter during an earth, and estimates the voltage at the earth position on the basis of the voltage of the DC bus and the voltage across the earth detection element before and after the change.SELECTED DRAWING: Figure 7