Analysis on wave peak ahead phenomenon of self-integral Rogowski coil

Abstract

To improve the measurement accuracy of self-integral Rogowski coil, the ahead phenomenon of its wave peak is analyzed. To find the authentic reason of this phenomenon, the equivalent parameter model of the sampling resistor is established. Both the analysis of the equivalent parameter model and experiment results show that distributed inductance in the sampling resistor is the critical factor for this phenomenon. Moreover, small resistance value leads to large ratio of inductance and impedance, which is the real reason for such phenomenon. The smaller the sampling resistance value is, the more probability of this phenomenon is. Versus, sampling resistor with larger value seldom causes this phenomenon. Therefore, to design the self-integral Rogowski coil, both the measurement dynamic range and the accuracy of measurement should be considered, and appropriate sampling resistors should be selected as well.