Research on Circuit Breakers in DC Microgrids

This paper focuses on research on circuit breakers in DC microgrids. Based on the introduction of fundamental DC microgrid concepts and basic models, it elaborates on the detailed refinement of DC microgrid modules and proposes a practical architecture for household smart DC microgrids. To ensure compliance with European microgrid standards, voltage levels are optimized through literature comparison, establishing appropriate voltage specifications. Furthermore, the paper introduces a DC Bus Voltage Signal (DBS)-based control strategy for DC microgrids, including converter control algorithms for renewable energy sources and energy storage devices. The control implementation typically involves voltage/current sensing modules and PWM signal generation for power semiconductor switching. For enabling interaction between loads and the DC bus, a novel intelligent DC circuit breaker topology based on soft-switching technology is proposed and validated through simulation. The breaker's operation principle employs advanced gate driving techniques and snubber circuits to achieve zero-current mechanical switching interruption. It can also function as a fundamental module for power routers, realizing energy routing concepts through solid-state switching control algorithms, thereby providing new directions for DC microgrid development.