Magnetic current sensor stray components in high frequency operation and their effects

Some of the most severe faults in electrical power networks are caused by faulty insulation or short-circuits. These events are accompanied by traces of partial discharges and traveling waves and recording such pulsed signals accurately is the key for providing effective on-line status monitoring of power lines. Capturing the high-frequency transients is very essential to protection means of local power systems employing power converters and smart-grids [1]. In this paper, operation of an inductive current sensor for on-line measurements is analyzed at high frequencies. Analysis focuses on the aspects of external components used with the sensor but also the connecting components linking the sensor to the measurement circuitry. Some practical aspects are discussed that can help to improve measurement accuracy and effectiveness.