Assessment of high frequency performance of voltage instrument transformers using the relative application bandwidth

Inhalt:
Measurements of harmonic and interharmonic voltages are of crucial importance for the assessment of voltage quality also in high voltage grids. Historically, voltage instrument transformers (IT), according to IEC 61869, have been specified and mainly used for rated frequency (fr) measurements at 50/60 Hz. Due to changing requirements, standardization and research projects have addressed this field, and high frequency (wideband) accuracy characteristics, dependencies and test methods have been introduced and analyzed in the recent past. As one new performance parameter for ITs, this paper discusses the relative application bandwidth and shows the application of a low voltage test method on a range of various types of conventional and low-power instrument transformers.