Design and development of Rogowski coil with nickel alloy flexible filament core

In electrical systems, current transformers are generally used for the generation of current in the lines. In current transformers, core saturation can be observed according to the measured current magnitude. Hall effect sensors or air-core Rogowski Coils (RB) are also used for the current measurement. Hall effect sensors can be greatly affected by external magnetic environments. RBs using an air core are magnetically linear. For this reason, RBs can make high-accuracy measurements in the measuring range. Moreover, RBs are flexible, so they can be used easily in any environment and can be disassembled and reassembled. However, because of air-cored, the secondary voltages of the RBs are measured at mV. They are used with an indicator on the secondary side to obtain meaningful values. Therefore, current sensitivities may be low when amplifier and ADC resolution are taken into account. In this paper, a flexible ferromagnetic core RB design has been developed to increase the current sensitivity of commercial RBs. For the production of flexible core, %40 and %60 nickel alloy filaments have been produced. Air core and filament core model of RB, which was developed considering a commercial reference product, was produced in the laboratory and experimentally compared with each other in the range of 0-400 A with MAPE (%) values. Accordingly, the voltage values measured with the proposed RB are on average 25% higher than that of the air core RB. This will contribute positively to measurement accuracy.