10kV开关柜套管内壁沿面场强计算及结构优化

Surface field strength calculation and structure optimization of the inner wall of bushing for 10 kV switchgear

针对开关柜穿墙套管面临的绝缘问题,提出了一种套管结构的优化方法。以无屏蔽结构的10 kV开关柜穿墙套管为研究对象,建立了有限元模型并提取了套管内壁的沿面电场分布。讨论了不同优化方法对套管沿面场强分布的影响,确定了将限位板端部变为斜面的优化方法,并基于电场计算结果确立了穿墙套管结构的最优参数。结果表明在限位板端部增加沿母排方向高度为15 mm、宽度为20 mm的斜面,可有效提高套管的耐压强度,套管表面的沿面最大场强降低了44.3%,计算结果验证了优化方法的有效性。

Aiming at the insulation problem faced by the switchgear bushing,an optimization method of bushing structure was proposed in this paper.Firstly,the finite element model of the wall bushing of 10 kV switchgear was established and the distribution of the electric field along the inner wall surface of the bushing was extracted.The influence of different optimization methods on the electric field distribution along the bushing surface was discussed.Then the optimization method of changing the end of the limit plate into an inclined plane is determined,and the optimal parameters of bushing structure were proposed based on the results of electric field calculation.The result showed that the voltage withstand strength of the bushing increased effectively while the end of the limit plate has a slope with 15 mm height along the bus bar and a thickness of 20 mm.In this structure,the maximum surface field strength of the bushing decreased by 44.3%.The calculation results verified the effectiveness of the optimization method.