虚拟仪器在氧化锌避雷器泄漏电流在线检测中的应用

Application of Virtual Instrument on On-line Measurement of Leakage Current of Zinc-oxide Lightning Arresters

传统的仪器结构由于有限的数据处理能力 ,难以完成复杂的信号处理任务 ,从而使测量准确度难以进一步提高。这里采用虚拟仪器实现氧化锌避雷器泄漏电流的在线检测 ,不仅极大增强了仪器的智能化程度 ,同时为复杂、有效的信号处理手段的应用提供了广阔的空间。在信号处理方面 ,采用小波技术对现场信号进行消噪处理。对消噪后的信号 ,利用信号的相关分析推算出阻性基波泄漏电流。采用这样的分析方法 ,测量准确度得到显著提高 ,从而增强了设备故障诊断的可靠性。

For the problem of leakage current measurement for zinc oxide lightning arresters, data processing technique is the key to improve the accuracy and reliability of measurement. However, for traditional instruments it is difficult to carryout a complicated and effective signal analysis tasks because of their limited ability of data processing. In this paper, a virtual instrument for leakage current measurement is presented. By this construction, more effective signal processing techniques, such as wavelet transformation and correlation analysis, can be completed easily. By wavelet transform, the leakage current is picked up from noise firstly, and for the signal with noise removed, the correlation analysis is then used to compute the resistive fundamental harmonic leakage current.