Rogowski coil with a non-inverting integrator used for impulse current measurement in high-voltage tests

• This study presents design and construction of an impulse current measuring system based on a Rogowski coil with a non-inverting integrator.
• The Rogowski coil with the developed integrator is designed as a clamp-on device, so it is convenient for installation in the real practice.
• The wide bandwidth frequency of the developed measuring system is designed from 1 Hz to 2 MHz.
• From the experimental results, it is found that the developed measuring system shows very satisfied performance for measurement of the fast rise time current with front time of 1 μs and the long-duration impulse current with the duration time of upto 2 ms.

This paper presents design and construction of an impulse current measuring system based on a Rogowski coil with a non-inverting integrator used for impulse current measurement in high-voltage tests. For convenience in current measurement in the high-voltage tests, the developed Rogowski coil is specifically designed as a clamp on device. For verification, the developed current measuring system was tested in comparison with a non-inductive shunt resistor and the same Rogowski coil with previous developed integrators. The various standard impulse currents, i.e. the steep impulse current (1/20 μs), the high impulse current (4/10 μs), the lightning impulse current (8/20 μs), the switching impulse current (30/80 μs), and the long-duration impulse currents with duration time of 1−3 ms were generated for comparative measurement in a high-voltage laboratory. From the experimental results, the developed Rogowski coil with the proposed non-inverting integrator has fairly high accuracy in wide frequency bandwidth covered the frequency bandwidth of the standard impulse currents in high-voltage tests. It can be concluded that the developed current measuring system has a promising characteristic being appropriate for measurement of impulse currents in high-voltage tests.