检测电阻电流型电子式电压互感器

Resistance current detecting based electronic voltage transformer

针对目前各种电压互感器存在的技术问题,提出通过检测耦合电阻电流实现的电子式电压互感器(ETV)的新原理和新方法.详细分析新型EVT的传感原理,建立了电压互感器一次侧等值电路,给出误差计算公式;并对影响测量精度的高压电阻特性和杂散电容因素进行理论性分析,提出相应的改进方案。研制了10 kV电子式电压互感器样机,准确度测试结果表明:该互感器准确度满足IEC 60044-7标准要求,准确度达0.2级.

A variety of voltage transformer technical problems emerging,a new Electronic Voltage Transformer（EVT） method is proposed by detecting micro-current in a coupling resistor in this paper.The new type of EVT principle is analyzed,the equivalent circuit model for the voltage transformer primary side is also established,and the error formula is presented.The high-voltage resistance and the distributed capacitance characteristics,which have influence to the EVT precision,are analyzed,an improved scheme is proposed.A prototype of 10 kV EVT is developed.The accuracy test results show that the EVT can meet the standard of IEC 600447 with accuracy of 0.2.