Breakdown characteristics of liquid nitrogen under composite voltages

In the present work, a carefully designed experimental set up has been used to measure breakdown voltages (BDV) of LN₂ under realistic conditions which are likely to be encountered in the complex electrical systems in the field. Different electrode profiles viz. sphere-sphere, needle-plane has been used to simulate various practical conditions. The Authors particularly focuses on the breakdown characteristics of LN₂ under composite voltages viz. AC superimposed with positive DC, AC superimposed with negative DC. It is observed that DC bias reduces the AC breakdown voltage considerably.