一种基于SV采样信号的局部放电监测内同步基准修正方法

A synchronous reference correction method based on SV Sampling in partial discharge monitoring

高压设备局部放电信号与设备运行的工频电压具有高度的相关性,局部放电监测装置或仪器必须基于稳定可靠的工频相位信号才能正常工作。针对现有电子互感器应用场合局部放电基准相位无法引入的难题,提出一种基于SV采样信号的局部放电监测内同步基准修正方法:首先利用装置自身定时器生成一个虚拟工频周期的"内同步"信号,利用该信号对各个传感器输入信号进行相位预标定;接收合并单元送来的电压互感器的SV信号并以其作为基准对虚拟的工频相位进行修正,从而得到精确和可靠的工频相位基准。所述方案实现简单,对于常规互感器和电子互感器均适用,具有灵活性和普及性。

The partial discharge signals of high voltage equipment are highly correlated with the power frequency volt- age of operating equipment, and the PD monitoring devices or instruments can work properly based on the stable and reliable power frequency phase signals. According to the problem that PD reference phase cannot be introduced into the applications using electronic transformer, this paper presents a discharge monitoring internal synchronization refer- ence correction method based on the SV sampling. Firstly, the internal timer of device is used to generate a virtual frequency cycle, which is the internal synchronization signal, and then, the signals are used to pre-calibrate the input signals of internal synchronization; secondly, the virtual frequency phase is used to amend the SV signals provided by the combined units, after this, we can get accurate and reliable frequency phase reference. Whether conventional or electronic transformers, this scheme is very simple to implement and has the flexibility and popularity in engineering applications.