不同工作频率对自能式SF_6断路器开断性能影响的仿真研究

Simulation Research of Influence of the Different Operating Frequency on Interrupting Performance of Self-blast Type SF_6 Circuit Breaker

国内断路器产品常采用50 Hz工作频率,国外断路器产品常采用60 Hz工作频率。为了适应国外尤其是北美市场60 Hz运行条件的要求,迫切需要开展60 Hz运行条件下开断性能的研究。文中基于气流场仿真研究工作,针对某型252 kV自能式断路器,研究了同样产品在50、60 Hz运行条件下的差异性,对比分析了电流燃弧阶段温度分布、气压分布以及过零时刻的气流场特性和过零前电弧电导。结果表明,由于膨胀室压力的增加不足以匹配60 Hz频率下电弧能量的增加,导致50 Hz频率下的冷气流对过零时刻电弧的吹弧作用相对60 Hz频率下的更为充分。在电流过零时刻,同样产品在50 Hz的气流场特性以及电导特性相对60 Hz更加优良,有利于电流开断。

Most of the domestic circuit breaker products are worked under 50 Hz power frequency,foreign circuit breaker products are worked under 60 Hz power frequency.In order to meet the requirements of 60 Hz operating conditions in foreign countries,especially in North America,the investigations of interrupting performance under 60 Hz condition need to be carried out urgently.In this paper,an interruption simulation model of 252 kV self-blastcuit breaker is built,the characteristics and the differences of interruption under different power frequency are acquired for the same product.The gas temperature and gas flow field at different power frequency 50 Hz and 60 Hz are simulated and compared,much attention is paid to the comparison of arc characteristics and arc conductor under the two frequencies during current passing zero.The simulation results show that blowing strength of cooling gas to the arc 50 Hz is stronger than that 60 Hz during current passing zero,due to the pressurization within the expansion chamber is not matched to the arc energy for extinguishing under the 60 Hz.The arc performance and arc conductor under the 50 Hz is better than the 60 Hz at the current zero time,50 Hz is easier to extinguish.50/60 Hzself-blast type SFcircuit breakerarc modelarc conductor.