A rogowski coil with an active integrator for measurement of long duration impulse currents

This paper presents design and construction of an impulse current measuring system based on a Rogowski coil with a non-inverting active integrator. The developed measuring system was designed for measurement of millisecond impulse currents. The comparative measurements of the same Rogowski coil with various integrators and of a non-inductive shunt resistor were carried out in an HV Laboratory. In this paper, the performance of the developed integrator with the same Rogowski coil was compared with that of other integrators (a conventional RC integrator, a compensated RC integrator and an inverting active integrator). From the experimental results, the proposed active integrator provides promising performance comparable to that of the non-inductive shunt resistor. This accomplishment will be useful in measurement of long duration impulse currents and also evaluation test of surge arrester.