Analysis of DC Pole-to-Pole Fault for converters in MVDC Shipboard Power System

Abstract

In Medium voltage direct current (MVDC) shipboard power system, extensive use of power electronics is required for connecting devices to the MVDC bus. Due to the high discharge ability of the dc-link capacitor of converters, the pole-to-pole short circuit (PPSC) fault will make a fatal effect on the system. Moreover, the lack of operational experience and appropriate fault analysis techniques of different converters also limit the development of MVDC protection. This paper explores the dynamic behavior for different types of converter during PPSC fault. The fault current transient processes are analyzed in detail with the detailed operation simulations. An expediently fault current analysis method based on equivalent circuit model is proposed. The results of simulations show that the proposed method is effective for different types of converters, and it can replace the detailed simulation model in the future study of MVDC protection technology.