In High Voltage Domain and Power Laboratory, requires to measure the high frequency current values. Using Current Transformers (CT), to measure these high current values. CTs reduce high currents to a much lower value and provide a convenient way of safely monitoring the actual electrical current flowing in an AC transmission line using a standard ammeter. Secondary current in a CT will become distorted if the CT becomes saturated because of a large primary current. This distorted current may lead to a malfunction in the protective relay because it receives a smaller current during the period of the fault occurrence. Therefore, detection and correction of the distorted current caused by the saturated CT is essential. Rogowski Coil is an electrical device used for measuring alternating current such as highspeed transient; pulsed currents or power frequency sinusoidal currents. In its simplest form a Rogowski coil is an evenly wound coil of N turns per meter on a non-magnetic former of constant cross-sectional area A. An alternating or pulsed current in a conductor develops a magnetic field and the interaction of this magnetic field and the Rogowski coil local to the field gives rise to an induced voltage within the coil which is proportional to the rate of change of the current being measured. Rogowski coil is dependent mainly on the adopted reconstruction methods. The proposed method utilizes numerical differentiation reconstruction method providing accurate as well as reduced time for correctly tracking the measured current. The proposed reconstruction method proved accurate measurements as well as fast tracking of the measured current.
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