Attenuation and deformation characteristics of lightning impulse corona traveling along bundled transmission lines

Comprehensive study of the impulse corona characteristics is helpful to understand the transient process and guarantee a suitable insulation design of power transmission systems. In this paper, first the attenuation and deformation characteristics of lightning overvoltage traveling along a 500 kV experimental transmission line are tested. Then the lightning impulse corona characteristics on different bundled conductors commonly used in the 110–1000 kV power transmission lines are experimentally investigated, the impulse corona Q–V data measured in the corona cage is transformed into those on the corresponding overhead lines. The influence of bundle geometry on corona is analyzed. Attenuation and deformation effects of lightning impulse corona along transmission lines are evaluated by comparing the simulation and test results. Simulation shows the amplitude and wave-front steepness attenuate remarkably, and the deformation of the voltage mainly happens when the impulse voltage exceeds the corona inception one.