电器试验中微机应用的研究

电器强电流试验的特点是:捕捉较长的、含有高频分量的暂态信号.国内外一般的暂态记录仪,由于内存容量小和精度低,满足不了电器试验的要求.本文根据电器试验中的熔断器试验要求,设计出了一利用微机的高速瞬态数据采集处理系统.其特点是:采样速度快、分辨率高、内存区较大、通道可扩充,能够捕捉到不同试验电流情况下的试验信号.经过数据的处理,可求出试验的各种参数.对电器试验回路的时间常数和功率因数,用 IEC 标准和国家标准提供的方法求解时,其准确度较低.本文首次提出用 Marquardt 法拟合暂态合闸电流来求取时间常数和功率因数,获得了较为准确的结果.

ON APPLICATION OF MICRO-COMPUTERS IN ELECTRIC APPARATUS TESTS

It is of especial importance in strong current tests for electric apparatus that longer transient signals containing high frequency components are cap- tured.The general transient signal recorders obtainable on world markets cannot meet the requirements of these tests because of the small storage capacity and inaccuracy of these instruments.In accordance with test requirements for fuses, taken as a typical piece of electric apparatus,a transient data sampling and processing system with micro-computers is designed and reported in this paper. It is characteristic of this system that the sampling speed and the resolution power are high and even larger storage capacity can be incorporated,and also the number of channel multiplicity can be increased.Under various test con- ditions,transient signals can be captured by this system as desired.All kinds of parameters needed can be easily acquired by data processing.Marquardt's method is first used in this paper to fit the curve of transient closing current. Using this method,the time constant or power factor can be readily acquired, and a quite accurate result can be achieved.