AMF electrode diameter simulation for HV vacuum interrupter

Abstract

The objective of this paper is to study how big an electrode is needed for 31.5kA short-circuit breaking capacity at high voltage ratings. First, three types of π65mm electrodes are created with AMF density and contact gap enhanced step by step, and their models are established. Then the AMF density and distribution on each contact surface and intermediate plane at kA peak current are simulated by using finite element software Maxwell 3D; their effective area A and utilization U are calculated with critical AMF density of 4mT/kA. Finally, based on the achieved 31.5kA effective area A0 at 12kV, the needed electrode diameter at high voltage ratings is obtained.