The Principle and Method of Improving Short Circuit Ratio of LCC-HVDC by VSC-HVDC

Abstract

Abstract. VSC-HVDC has significant impact on LCC-HVDC in hybrid-infeed HVDC system. Based on a hybrid dual-infeed HVDC system, the multi-infeed effective short circuit ratio is deduced which quantitates the improvement effect of VSC-HVDC to LCC-HVDC. Considering both the normal operation target of VSC-HVDC and the transient voltage compensation needed by LCC-HVDC, a control strategy of VSC-HVDC is proposed which can achieve maximum MIESCR.