Performance of the Pramod Johns scheme for UHS protection of EHV transmission lines under arcing fault conditions

The performance of the scheme of Pramod Agrawal (1989) for ultra-high-speed (UHS) protection of EHV transmission lines under arcing fault conditions is described. The arc with reignition effect is modeled, and a method for digital simulation of the superimposed arc voltage is discussed. Simulated tests have shown that the arc voltage has significant higher-frequency components. These tests also confirm that the arcing fault response repeats every half-cycle for a fault inception angle of the voltage from 0 to 90°, which is a significant improvement over schemes based on traveling-wave phenomena which have been considered a failure for faults at 0°C fault inception