空气直流断路器开断特性的分析验证

Analysis and verification of the opening characteristic of DC circuit breaker

针对直流断路器在开断过程中电弧熄灭比较困难的问题,对空气直流断路器的开断特性进行了分析研究。分析了如何有效的缩短电弧的燃烧时间,研究了时间常数对断路器开断能力、电弧电流上升率的影响及断路器开断电流的大小与燃弧时间的关系。基于上述研究分析,制造出了样机,并利用高压直流试验台模拟不同的短路故障电流对直流断路器进行了多次开断试验测试,获得了很多试验数据,研究结果表明:断路器在额定电压为DC1800 V,能够可靠切除短路故障电流达到80 k A,断路器开断电流随着时间常数的增大而减小,燃弧时间随着开断电流的增大而减小。

Aiming at the problem that electric arc was difficult to extinguish in the process of DC circuit breaker interrupting,the interrupt characteristics of the DC circuit breaker were analyzed. How to shorten the combustion time of the arc was analyzed by this paper,and the influence of the time constant on the breaking capacity of the circuit breaker,the rising rate of the arc current and the relationship between the current of the breaker and the arcing time was studied. Based on the above analysis,created a prototype,and open circuit was tested for many times by using high voltage DC test rig simulation about different short circuit fault current of DC circuit breaker,won a lot of experimental data. The results show that the circuit breaker in the rated voltage is DC 1800 V,which can reliably remove fault current to 80 kA,circuit breaker fault current decreases with time constant,arcing time decreases with the increase of breaking current.