Development of an AC Standard Shunt With SmallPhase Angle and High Stability

摘要

The authors developed an ac standard shunt, rated 10 A, 0.1 Ω, for the frequency from dc to 10 kHz that has highly stable resistance value and small phase angle error. Using this ac standard shunt, ac power and current may be measured with high accuracy. The change in the resistance value of the ac shunt is within ±1 μΩ/Ω when the ambient temperature is (23±3)C. The change in the resistance value is 2.5 μΩ/Ω per year. The phase angle of the ac shunt is 6 μrad at 1 kHz. Stability of the shunt, which is calibrated once a year, corresponds to 3 μW/W of uncertainty with regard to ac power measurement at 1 kHz.