Effect of current heating on accurate measurements of AC shunt resistors

To propose a structure for high-accuracy shunt resistors, the frequency and current dependencies of AC shunt resistors with different current ratings are evaluated both for AC resistance and phase angle. To evaluate these characteristics, a modified current-bridge method was developed. The AC resistances of the shunts do not vary considerably with the frequency, up to 3 kHz. The phase angle of AC shunts varies proportionally to the frequency. The current dependence of the AC resistance of shunts seems to change with current value. The current dependence of the phase angle of the shunt remain stable up to 10 A.