氧化锌非线性电阻结构不均匀性的微机辅助诊断

The Computer-Aided Diagnosis on Inhomogeneity of Metal Oxide Varistors

金属氧化物非线性电阻(MOV)结构不均匀性是影响其通流容量的关键因素,为保证产品质量必须在生产过程中对其每一阀片之均匀性进行测验。本项目研究的目的是探索一有足够精度且有工业应用前途的无损缺陷检测法。 在一定电压作用下MOV之结构均匀性愈差,则其沿横截面之电流分布愈不均匀。基于此一内在联系,设计了一种可探测电流沿面分布的采样电极及数据实时探采系统,通过微机数据处理,得到显示MOV不均匀性的特征数据。又通过理论分析提出了其判断指标。通过对数十片试品的试验结果分析证明了通流容量试验时击穿点位置几乎完全与估计相符合,通流容量也有较好的对应关系。本装置能迅速给出并打印试品的特征数据并作出等级判断,适合工业应用。

The inhomogeneity of Metal Oxide Varistors (MOV) is a key factor that influences its discharge capacity. In order to guarantee the quality of the product, it is necessary to test the homogeneity of every element during the process of the production. The purpose of the research is to search for a method of flaw detection without damage which is accurate enough and has some industrial prospect.Under certain voltage,the worse the homogeneity of MOV's structure, the more inhomogeneous the distribution of electric current crossing the section of MOV. Based on this reationship, a data-gather electrode and a simultaneous data gathering system are designed. With the help of microcomputer, the characteristic data of the MOV's inhomogeneity is shown, and its judge target is also obtained through analysis. The testing results proved that the breakdown piont on the samples in discharge capacity test is almost compatible with what has been predicted by the electric current distribution test and the discharge capacity of the samples has good corresponding relationship to the disribution of eectric current. The presented device can quickly give and print the characteristic data of the sample and make the grade judgement. It is highly suitable for industrial use.