Cascade multi-level converter based DVR and D-STATCOM for voltage sag and swell reduction

This paper presents the modeling and simulation of three and seven-level cascade multilevel converter (CMC) based dynamic voltage restorer (DVR) and distribution static compensator (D-STATCOM), aimed at correcting the supply voltage sag/swell and interruption in low voltage distribution networks. The proposed design models of CMC based DVR and D-STATCOM are expected to be most powerful solutions to minimize supply voltage disturbances of the sensitive loads. The proposed models of DVR and D-STATCOM together with the controllers are simulated by using electromagnetic transient simulation program (PSCAD/ EMTDC) and the results are presented to assess the performance of each device.