绝缘子表面放电的多物理信号比值演化特征及其诊断方法研究

为了探索局部放电声、光、电信号特征及演化规律,并利用多物理测量手段进行局部放电诊断,本文基于电流脉冲、地电波、超声及光学测量建立了局部放电多物理同步检测试验平台,并以强、弱垂直分量绝缘子沿面放电为例,通过试验研究了其局部放电多物理信号强度比值的演化特征。在此基础上,建立了一种三角比值空间分析方法,得到了各物理信号随电晕时间的演化特征。结果表明:虽然不同模式放电的三角比值散点分布区域不同,但其超声分量均随时间的推移呈现"U"型的演化路径,其演化速度和演化轨迹在放电初期、电晕稳定期和临近击穿期呈现出较大的差异,可作为局部放电危险程度的评判依据。

Multi-physical Signals Specific Value Evolution Characteristics of Surface Discharge Along Insulator and Its Diagnosis Approach

In order to explore the sound, light, and electric signals and their evolution law of partial discharge(PD) and use multi-physical test methods to diagnose PD, a multi-physical synchronous PD test platform was established on the basis of current pulse, transient earth voltage(TEV), acoustic emission(AE), and optical emission(OE) measuring. Taking strong and weak vertical field discharge(SVD and WVD) on insulator as example, the evolution characteristics of PD multi-physical signal specific value was studied by experiments. A triangle ratio spatial analysis method was proposed, and the evolution characteristics of each physical signal with corona time was obtained. The results show that the scattered point of triangle ratio of different discharge distributes in different areas, but the evolution path of AE components with time present U-type. Both of SVD and WVD present obvious differences in the initial stage of discharge, stable stage of corona, and pre-breakdown stage.