检测电流型电子式电压互感器的开发及精度分析

Development and Precision Analysis on Electronic Voltage Transformer Based on Measuring Current

提出了一种高压电容器串接精密电流传感器,通过测量流经电容器的电流来反映一次电压变化的方法。精密电流传感器副边的感应电流经二次处理电路后可输出一个与一次高压成线性变化的电压信号,从而构成了基于检测电容电流型电子式电压互感器。高压电容器和精密电流传感器放置于开关站场地,通过铜导线将二次电流引入控制室,其它电子器件组装于机箱内放置在控制室以输出二次电压。针对影响电子式电压互感器的因素进行了分析,并对互感器做了相应的改进。文中提出的电子式电压互感器结构简单、体小质轻、无铁磁谐振、无须油箱及其绝缘介质,实验结果表明,其具有测量精度高、响应速度快、抗干扰能力强和工作稳定可靠等优点。

A precision current transducer connecting in series with high voltage capacitors, which can reflect the variation of primary voltage by measuring the current flowing through capacitors, is proposed. After the secondary processing of current induced in the secondary side of the precision current transducer, the output of the proposed current transducer is a voltage signal that is linearly proportional to primary high voltage, thus a current type of electronic voltage transformer based on measuring current is constructed. High voltage capacitors and precision current transducer are located in the site of switching station, through copper conductor the secondary current is led into control room, and other electronic devices is assembled in the case to output secondary voltage. The factors impacting this electronic voltage transformer are analyzed, on this basis the voltage transformer is improved. The proposed electronic voltage transformer is small, light and need not oil tank and insulation medium. Experimental results show that it possesses following advantages： high measuring accuracy, fast response speed and high anti-interference ability, and it can work steadily and reliably.