363kV快速真空断路器电场计算

Electric field calculation of 363 kV fast vacuum circuit breaker

高电压等级开关设备的绝缘水平严重影响设备的安全运行和开断能力,因此在研发高电压真空断路器时需要分析其电场分布。以363 k V快速真空断路器设计结构为原型,建立三维有限元电场计算模型,分别计算了额定电压下闭合和开断工况下的电场分布,分析了灭弧室、绝缘子以及主要金具表面的电场大小。结果表明:均压环表面电场最大值为1. 92 MV/m,绝缘子表面最大值为0. 36 MV/m,开距20 mm时灭弧室断口电场最大值为3. 5 MV/m,其他部位电场均处于控制范围内,断路器总体结构设计合理,满足绝缘要求。

The insulation level of high-voltage switchgear will affect the safe operation and breaking capacity of the equipment. Therefore,it is necessary to analyze the electric field distribution when developing high-voltage vacuum circuit breakers( VCB). Based on the prototype structure of 363 kV fast VCB,a three-dimensional finite element electric field calculation model was established. The electric field distribution of closed and open state with rated voltage were calculated respectively. The electric field of the arc extinguishing chamber,insulator and main fittings were analyzed. The results show that the maximum electric field of grading rings,and post insulator are 1. 92 MV/m and 0. 36 MV/m respectively. The maximum electric field of break is 3. 5 MV/m at the open gaps of 20 mm. Electric field of other parts are within the limitation. The overall structure of the circuit breaker is designed reasonably to meet the insulation requirements.