基于容性设备泄漏电流的电网电压测量方法

基于电容型设备泄漏电流，研究了电网工频电压和内部过电压的测量方法。采用高精度宽频带电流传感器检测容性设备的泄漏电流，通过有源积分电路将电流信号重构成电压信号。分析了容性设备等值电路及泄漏电流与电压的传递函数，研究了电流传感器的工作原理及其影响因素。通过采用有源积分器，提高了输出电压响应的幅频特性。采用的电压传感器结构简单，与高压系统无电气连接，具有很好的安全特性。工频和操作过电压实验结果表明，所设计的电压传感器具有很好的精度和线性度，可以用于高压电网的电压测量。

Power Grid Voltage Measurement Based on the Leakage Current of Capacitive Equipments

Based on the leakage current of capacitive equipments, a measurement method of power voltage and internal over-voltage is presented. A high precision and wide-band current sensor is used to detect the leakage current of a capacitive equipment. The current signal is converted into voltage signal by an active integrator. The equivalent circuit of the capacitive equipment and the transfer function between voltage and leakage current are analyzed. The principle and influential factors on the current sensor performance are also studied. By using the active integrator, the amplitude-frequency characteristic of the output voltage is improved. The adopted voltage sensor is very simple in structure and very safe because it has no direct connection with the high voltage system. Experimental results of power frequency voltage and switching over-voltage indicate that the voltage sensor has very good precision and linearity, and can be used to measure the voltage of high voltage power grids.