基于零电压零电流的混合式直流断路器

摘要

基于IGBT的直流断路器存在导通损耗高、开断过程耗能量大的缺点，传统基于人工过零技术的直流真空断路器难以实现短路大电流的可靠开断。提出了一种综合了“零电压”、“零电流”混合开断原理，同时结合机械开关和半导体开关优点的新型混合式直流断路器方案。该直流断路器能够快速可靠地完成“零电压”电流转移过程，并通过晶闸管短时导通短路电流，确保机械开关弧后介质的可靠恢复，实现断路器的成功开断。样机等效短路电流开断试验结果表明，该新型混合式直流断路器能够用于电力系统配网完成预期10 kV/50 kA短路电流的开断。%The weakness of the DC circuit breaker scheme based on IGBT lies in relatively higher on-state loss and more energy ab-sorbed in the breaking process, while the traditional DC vacuum circuit breaker scheme based on forced current commutation technolo-gy could not interrupt large short circuit current reliably. A novel hybrid DC circuit breaker based on a“zero voltage” and“zero cur-rent” hybrid breaking principle is proposed in this paper, which combines the advantages of mechanical switches and power semicon-ductors. The novel circuit breaker could finish the current commutation quickly and reliably in the “zero voltage” process, and then conduct the short circuit current by the thyristor, enabling the switch achieve the dielectric recovery reliably, making the DC current in-terrupted successfully. Equivalent current breaking test results of the breaker prototype indicate that the novel hybrid DC circuit breaker is able to interrupt the prospective 10 kV/50 kA short circuit current in the real system.