Abstract：An improved electronic voltage transformer (EVT) based on direct detecting capacitor current is designed in this paper. The EVT offers a variety of advantages, such as: small size, simple structure, no ferroresonance, high insulating strength, high anti-interference capability, good temperature characteristics, and the transient performance is not influenced by the retained charge of the high voltage capacitors, etc. The working principles are analyzed in detail, and the solution of the EVT is designed. The temperature compensation method that employing a number of capacitors half with positive temperature coefficient while the other half with negative temperature coefficient in serial connection to comprise the high voltage capacitor is proposed, which can improve the stability over temperature. The theory and simulation analysis on the frequency characteristic, transient performance, and anti-interference capability of the EVT were carried out. Subsequently a 10kV electronic voltage transformer has been developed. And the accuracy test, power-frequency withstand voltage test, and temperature test were conducted. The simulation and the tests show that the proposed EVT is fully compliant with IEC 60044—7 standard, assuring 0.2 measurement precision class and 3P protective class.
邵霞, 周有庆, 彭红海. 一种改进的直测电容电流型电子式电压互感器[J]. 电工技术学报, 2013, 28(4): 240-247.
Shao Xia, Zhou Youqing, Peng Honghai. An Improved Electronic Voltage Transformer Based on Direct Detecting Capacitor Current. Transactions of China Electrotechnical Society, 2013, 28(4): 240-247.
2013, Vol. 28 
