Error source determination of a magnetoresistive active power sensor at industrial frequencies

In this paper, the results of the experimental investigation of the error sources of a magnetoresistive active power sensor at the industrial frequency of 60 Hz are presented. The investigation has been carried out at 120 V and 1.0, 5.0, and 10 A with the aid of a power calibrator. The current and phase shift in this experiment was held to within 30 ppm and the voltage was held to within 9 ppm, respectively. The main sources of the uncertainties are phase uncertainty of the voltage divider, self-detection of the voltage and current signals, thermoelectricity, nonlinearity of the volt-watt characteristic, and the temperature instability. The total uncertainty of the magnetoresistive active power sensor does not exceed 0.2%.