Comparison of Different Technologies for Improving Commutation Failure Immunity Index for LCC HVDC in Weak AC Systems

Flexible AC Transmission System (FACTS) devices and Voltage Source Converter (VSC) High Voltage Direct Current (HVDC) systems have fast reactive power control capabilities which can be used to increase power system voltage stability. When located near a Line Commutated Converter (LCC) HVDC converter they can be used to support the performance of the LCC HVDC. This paper shows how well VSC HVDC, Static synchronous Compensation (STATCOM) and Static Var Compensators (SVC) are able to support LCC HVDC based on their improvement of the LCC HVDC Commutation Failure Immunity Index (CFII) and presents a comparison of their relative capabilities.