Recover the Low-Frequency Primary Voltage of Electromagnetic Voltage Transformers with LabVIEW

Electromagnetic voltage transformer (EVT) is a piece of crucial voltage measurement equipment in power system. However, the core of EVT may suffer from deep saturation with the excitation of power-frequency overvoltage, ferroresonance, DC bias, and energization. Once the core is deeply saturated, the secondary voltage of the EVT might be distorted, and the relative error can step up to 60%. Thus, the system voltage cannot be correctly recorded using EVTs. In this paper, we propose a method of recovering the low-frequency primary voltage with distorted secondary voltage of EVTs through designing a system with LabVIEW Based on the National Instrument (NI) platform.