On the Remote Calibration of Instrumentation Transformers: Influence of Temperature

The remote calibration of instrumentation transformers is theoretically possible using synchronous measurements across a transmission line with a known impedance and a local set of calibrated voltage and current transformers. In this paper, an extension of the research results presented in our paper “On the Remote Calibration of Voltage Transformers: Validation of Opportunity” published in AMPS 2018 was undertaken by reporting on how temperature could increase the measurement uncertainty contributed by voltage and current transformers. This was needed to better understand if remote calibration could be realized under real-world conditions where temperatures at different geographical locations could be significantly different. This paper describes the influence of magnetic voltage, current transformers, and capacitive voltage transformers. Based on the research in this paper, one could conclude that the influence of magnetic voltage transformers (MVTs) is low, but, especially with current measurement transformers and capacitive voltage transformers, errors should be considered when performing remote calibrations on measurement transformers over long distances with different environmental conditions.