Design of a 27-level cascaded converter as FACTS device for voltage sag mitigation

Abstract

One of the major problems with power quality is the voltage sag phenomena. There are various solutions for sag mitigation in the power system at the transmission voltage level, but the most common way is by installing mitigating devices in the system such as Flexible AC Transmission System (FACTS). This paper proposes a three-phase 27-level converter with unequal DC sources as a static synchronous series compensator (SSSC) for voltage sag mitigation at the transmission voltage level. This paper presents the design and control of a 27-level cascaded converter with unequal DC sources without using filters and have a fast response. This paper also shows the feasibility of the control for the 27-level cascaded converter with unequal DC sources as FACTS devices using the PSCAD software.