Modeling and control of a novel transformer-less dynamic voltage restorer based on H-bridge cascaded multilevel inverter

This paper describes a transformer-less DVR which employs a cascaded H-Bridge multilevel inverter. The proposed DVR is introduced through the system structure, the operation principle and switching scheme. Then an accurate and well-defined model is constructed in both ABC and DQ coordinates. Based on the proposed model, this paper presents an extensive analysis on the development of a suitable controller. Simulation results show that the proposed cascaded H-Bridge multilevel converter based DVR reacts fast to supply and load disturbances, making it has a good prospective in the industrial application.