Recording of Transients in 0.4—500 kV Electric Networks

A digital recorder of transients in 0.4-500 kV electric networks equipped with contactless sensors is presented. The voltage measurement principle used in the sensor is based on a certain electric field distribution between live conductor and "earth". The voltage sensors are calibrated remotely with respect to the nominal voltage. The voltage recording results have been viewed in the forms of a chart recorder and waveforms of impulse and low-frequency transients. The operation of the recorder equipped with contactless sensors has been verified experimentally at the NRU MPEI laboratory using a 1 MV pulse voltage generator. High-frequency switching overvoltages occurring in 10–500 kV switchgears of power plants and substations have been recorded.