With the continuous growth of photovoltaic (PV) power generation capacity and the gradual increase in DC side voltage levels
new requirements have been imposed on circuit breakers to achieve rapid full-current interruption under high-voltage conditions. To realize fast and arc-free interruption
this paper proposes an oscillation-circuit-based controllable Z-source DC circuit breaker (OCZ-DCCB). In the proposed topology
by controlling the conduction of the silicon controlled rectifier (SCR)
the capacitor C in the pre-charging branch is charged during normal system operation. This facilitates the generation of an oscillating current via the capacitor and inductor in the oscillation branch
thereby achieving rapid interruption of the full load current (10 A to 10 kA) in the DC line. Furthermore
the proposed design effectively addresses the issues of thyristor self-commutation failure under insufficient fault current rise rates and transient false triggering
which are common limitations in traditional Z-source DC circuit breakers. Compared with the active Z- source DC circuit breaker (AZ-DCCB)
the OCZ-DCCB reduces the fault current interruption time by a factor of 22 at DC 150 V. Under a short-circuit fault condition at DC 1 500 V
the interruption time for forward and reverse energy flows is 0.30 ms and 0.25 ms
respectively
verifying the rapidity and effectiveness of the proposed scheme. By integrating with the fully controlled device insulated gate bipolar transistor (IGBT)
the structure effectively utilizes the IGBT to meet complex energy flow demands in DC microgrids
enabling proactive and scheduled current interruption. The OCZ-DCCB is verified by simulation
and the results demonstrate its rapid interruption capability and adaptability to various DC grid voltage levels. These findings confirm its effectiveness and applicability
providing a novel solution for reliable full-current interruption of DC circuit breakers under high-voltage conditions.