Optimization Design of Interruption Characteristics of LVDC Hybrid Circuit Breaker

The low-voltage DC distribution system based on renewable energy has been widely developed because of the serious energy problem, in which circuit breakers play an important protective role. With the increase in breaking capacity, compared with traditional mechanical circuit breakers, hybrid circuit breakers have a longer service life and excellent breaking performance. Therefore, it is of great significance to study the breaking performance of hybrid circuit breaker. In this paper, a simulation model integrating arc model and behavior model of power electronic devices is established. The factors affecting the interruption characteristics mainly include line parameters and device parameters, which are analyzed by the above hybrid circuit breaker model. Among these factors, the time constant mainly affects the electric characteristics at commutation time. With the clamp voltage of MOV increasing, the energy dissipation time decreases obviously. The large stray inductance and parasitic capacitance have influence on the commutation process, which will extend the commutation time. This study may provide references for the selection and optimization of hybrid circuit breaker parameters and the improvement of breaking performance.