Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title Space Vector PWM Method for Leakage Current Reduction and NP Current Control in 3-phase 3-level Converter used in Bipolar DC Distribution System
Authors Eun-Chul Lee ; Nam-Sup Choi ; Hee-Jun Kim
DOI https://doi.org/10.6113/TKPE/2018.23.5.336
Page pp.336-344
ISSN 1229-2214
Keywords Bipolar DC distribution system ; 3-level converter ; Leakage current ; Neutral point current control
Abstract This study proposes a new PWM method for leakage current reduction and neutral point (NP) current control in three-phase three-level converter employed in bipolar DC distribution systems. The proposed PWM method uses medium vectors only when there is no need to control the NP current. Thus, common mode voltages are held constant to realize zero leakage current. Some space vectors that produce low-frequency common mode voltages are employed to minimize leakage currents when the average NP current needs to be a positive or negative value. The proposed space vector PWM is implemented based on barycentric coordinate. The validity of the proposed PWM method is verified by simulations and experiments.