Experimental study of transients and electrical fields caused by lightning flashover in the uhvdc converter station

When lightning strikes the DC transmission line and causes flashover, the transients propagating in the primary circuit and impulse electromagnetic field generated in the station might cause interference or even block fault of the UHVDC system. In this paper, artificial short-circuit (DC line to ground) experiments are conducted out on an operating ± 800 kV DC system at different distances to the converter station, to simulate the lightning fault process, meanwhile the transient voltages and currents as well as the electrical fields are measured by advanced sensors and high sampling rate devices at different points in the converter station. It´s the first time that such experiments are carried out on a ± 800 kV DC system, with a comprehensively study of both the circuit and filed lightning transient characteristics.