Mitigation of voltage unbalance in a low voltage bipolar DC microgrid using a boost-SEPIC type interleaved dc-dc compensator

Abstract

DC microgrids are gaining popularity as there is an increase in the usage of dc loads and rise in the penetration of renewable energy sources (RES). Furthermore, bipolarity in the dc microgrid is introduced to enhance the reliability and efficiency of the system. However, bipolar dc grids are prone to voltage unbalance across the both the poles of the dc grid due to unequal load distribution. In this paper, a novel method is proposed to mitigate the voltage unbalance in a bipolar dc microgrid using a boost-SEPIC type interleaved dc-dc compensator. In the proposed method, apart from the converter losses, the compensator doesn't consume or supply power. Hence, no active source is required in mitigating the unbalance. The proposed method reduces the current in the neutral line, thereby reducing the overall line losses in the bipolar dc microgrid. Simulation and experimental results are presented to validate the efficacy and feasibility of the proposed technique.