Reliability Evaluation of AC-DC Hybrid Grid Based on State Enumeration Method

Abstract

DC grid, which is more suitable for the integration of intermittent energy, should undergo a reliability evaluation before being put into production. This paper proposes the reliability model for AC-DC converter and DC-DC converter firstly. Then, a minimum load shedding model considering the interaction between AC grid, HVDC and DC grid is presented. Finally, based on the state enumeration, the reliability evaluation for the AC-DC hybrid grid is accomplished. The results show that moderate redundant SM and the reduction of IGBT and capacitance failure rate can significantly improve the reliability of the AC-DC hybrid gird.