Computation of EMI Fields Generated Due to Corona on High Voltage Over Head Power Transmission Lines

Corona generated pulsed currents on high voltage transmission line conductors radiate electromagnetic fields, which, in turn, can interfere with communication systems, and radio as well as television receivers operating nearby. In this paper, the corona generated electromagnetic interference (EMI) field in dB at an observation point near the ground has been computed assuming the ground as a perfect conductor. It has been observed that the interference field starts abruptly at the corona inception voltage and it increases with the voltage stress on the conductor. It is also observed that the EMI field reduces with increase in lateral distance and also with increase in frequency as well as the conductor diameters for the same line voltage