基于波形畸变故障预判技术对一起10.5kV过电压保护器事故的溯源分析

Traceability Analysis of a 10.5 kV Overvoltage Protector Accident Based on Waveform Distortion Fault Prediction Technology

以某水电厂的一起10.5 kV过电压保护器爆炸事故为例,笔者通过提取过电压保护器爆炸前后的暂态与稳态故障录波数据,对其故障过程中的电气特征信号进行了分析,溯源了事故前后电气波形畸变的特征及故障演变过程;并对故障后变压器高、低压侧的电流穿越转换特征进行了详细的对称矢量分析,判定了发生的故障类型。分析表明:通过大数据挖掘,提取相关电气波形的畸变特征,可以有效识别电气设备渐进性故障过程,做到提前预警和故障判定。该分析方法可以推广应用到发电厂、电站的事故溯源、预警和故障判定,对电站防止重大事故具有重要的意义。

Taking a 10.5 kV overvoltage protector explosion accident in a hydropower plant as an example,this paper analyzes the electrical characteristic signals during the fault process by extracting the transient and steady state fault recording data before and after the explosion of overvoltage protector,and traces the characteristics of electrical waveform distortion before and after the accident and the fault evolution process.A detailed symmetrical vector analysis is carried out on the current-crossing conversion characteristics of the high and low voltage side of the transformer after the fault,and the fault type is determined.The analysis shows that the distortion characteristics of related electrical waveform can be extracted by big data mining,which can effectively identify the progressive fault process of electrical equipment and achieve early warning and fault judgment.The analysis method can be applied to fault tracing,early warning and fault judgment of power plants and power stations,which is of great significance to prevent major accidents in power stations.