Analysis and Treatment of Electronic Voltage Transformers Exceeded Tolerance Problem

For speeding up of substation digitization processing, transformers do not need high efficiency signal output. In the high-voltage power system, the traditional voltage transformers have been gradually replaced by electronic voltage transformer. As electronic voltage transformer based on capacitive voltage divider´s excellent performance, it has become the best substitute of the traditional voltage transformer, widely used in power system. This paper presented the basic structure and analysis the experiment data. The main reasons of exceed tolerance problem is RC oscillating circuit and detention electric charge. By choosing a suitable value resistance, the problem has been solved. According to IEC60044-7, the ECVT reaches the requirement. It can completely meet the demands of the development of modern power.