MOA避雷器失效模型研究

Failure Model Research of MOA Arrester

研究了氧化锌压敏电阻的失效模式和MOA避雷器的失效原因。从数学上讨论阀片串并联时电位分布不均匀问题,并完善了基波阻性电流的整个数学计算模型。从理论上考虑各干扰要素的补偿。提出了避雷器器寿命衰减率、衰减系数矩阵、破坏力度和破坏力函数等相关概念。在考虑了出现热崩溃的临界功率损耗的基础上,构建了避雷器寿命衰减模型,并提供了避雷器失效估计的假设检验方法。与工程上的失效检测模型做了对比。

On the basis of the analysis through failure mode of the ZnO varistor and the reason of MOA arrester failure, the problem of uneven potential distribution for parallel and series valve plate from mathematics is dis- cussed, and perfected the whole mathematics calculation model for the fundamental wave impedance current in con- sideration of the compensation of all theoretically interference elements. It puts forward the arrester life decay rate, attenuation coefficient matrix, damage dynamics and destructive power function and other related concepts, and constructs the arrester life attenuation model while consider the critical power loss when the arrester appear heat col- lapse. Otherwise, it presents hypothesis test method for the arrester failure estimate comparing with the engineering failure detection model.