基于不对称半周期谐振直流断路器的低电弧熄灭应力设计

DC circuit breakers are critical components for ensuring the safety and stability of dc systems. In recent years, resonant dc circuit breakers (RCBs) have attracted significant interest due to their ability to generate multiple current zero-crossing points in mechanical switches and demonstrate high reliability. In such solutions, the oscillation frequency presents a critical design tradeoff: higher frequencies compromise arc extinction reliability, while lower frequencies escalate capacitor and overall costs. To address this issue, this article proposes an asymmetric half-cycle RCB (AH-RCB). The AH-RCB design simultaneously leverages high-frequency oscillation to accelerate current rise, thereby reducing capacitor and overall costs, while employing low-frequency oscillation to reduce mechanical switch current stress, thus enhancing interruption reliability. The topology and operating principle of the AH-RCB are elaborated in detail, a parameter design method is proposed, and a 12 kV prototype is built. Compared to the original symmetric RCB, the AH-RCB exhibits a 59% enhancement in breaking capacity under equivalent capacitance conditions, alongside a 30% cost reduction for identical interruption requirements.