A Novel Generation and Measurement Setup for the Characterization of MV Voltage Transformers From 9 kHz up to 150 kHz

This article proposes a generation and measurement setup for the characterization of voltage transformer (VT), both inductive as well as low power voltage transformers (LPVTs) at power frequency and from 9 to 150 kHz with waveforms having amplitudes at medium voltage (MV) level. It involves the independent generation of the fundamental tone and of the high-frequency components to produce the desired distorted test waveform. The generation of the fundamental frequency component, in MV amplitude range, is obtained by means of a step-up VT, whereas the high-frequency components are generated through a series-connected voltage amplifier. As regards the measuring stage, the fundamental tone is measured through a commercial divider. Instead, high-frequency tones are measured through a reference device, operating in the range [9, 150] kHz, specifically designed, realized, and characterized. As an application, the characterization of two commercial VTs, an inductive VT and a LPVT, are presented.