Design of Rogowski Coil with external integrator for measurement of lightning current up to 400kA

Lightning is one of the most serious disasters in the electrical power grid, especially in the ultra-high and extra-high voltage power systems. The measurement of the lightning current parameters is of great importance for the investigation of lightning protection. The literature shows given its significant advantages over equivalent current transducers, the Rogowski coil is an increasingly popular method for current measurement of high amplitude and high frequency. However, there is little report focus on the lightning measurement on the transmission lines. In this paper, the lumped parameter model of the Rogowski coil with an external integrator is established to deduce the transfer functions as well as the bandwidth of the coil. Relationships between the sensitivity and coil parameters, such as coil dimension, integral parameters and number of turns of the coil, are investigated. Results show that the sensitivity of the coil increases with the increase of the sectional area and number of turns, or with the decrease of effective magnetic path, resistance and capacitance of the integrator. Based on the analysis of the experimental results, a Rogowski coil of the bandwidth from 2 kHz to 2 MHz and average sensitivity of 0.1144V/kA is developed for the measurement of lightning current up to 400kA. Furthermore, it is found that the measuring uncertainty is always caused by the off-center position of the current flowing through the coil. Combined with the affiliate circuit, the lightning current transducer is used to measure and locate the lightning current on the transmission line based on the designed Rogowski coil with external integrator. Streszczenie. Pomiary prądów wyładowań atmosferycznych odgrywają dużą rolę w zabezpieczeniach. Obecnie pasek Rogowskiego staje sioę coraz popularniejszym narzędziem pomiaru prądów o dużej amplitudzie i dużej częstotliwości. W artykule przedstawiono cewki Rogowskiego w zastosowaniu do pomiarów w liniach przesyłowych. Zaprojektowano czujnik o pasmie częstotliwości 2 kHz – 2 MHz i czułości 114 mV/kA. (Projekt cewki Rogowskiego z zewnętrznym układem całkującym do pomiaru prądów wyładowań do 400 kA)