Ac breakdown of air gaps in high voltage power networks in the presence of desert pollution

Abstract EN

This paper discusses the influence of air borne and electrode adhering dust pollution on electrical breakdown of air insulation using rod-rod, rod-plane, and sphere-sphere electrode gaps under alternating voltages.

Extensive experimental measurements are carried out in clean and polluted (gap/electrode) conditions by generating artificial dust storms.

It is shown that not only the dust pollution but a thin dust film formed on the high voltage electrode can also significantly reduce the breakdown voltage.

The presence of such a film increases corona pulse activity.

Negative space charge is found to be a major cause behind this antagonistic behavior.

Various other mechanisms which control the breakdown processes in the presence of dust pollution are also explained in the light of experimental evidence.