Challenges For Vacuum Interrupter Design

Vacuum interrupters form the key component of a medium voltage (MV) vacuum switchgear design. Vacuum interrupter technology is now well established and key manufacturers across the world are routinely producing interrupters for ratings up to 52kVrms. Manufacturers have focused on reducing the cost of interrupter components by adapting to more efficient contact geometry, improved contact materials, finite element modelling for improved field distribution and new processing techniques. However, these methods are now such that further cost reductions are becoming difficult. This may become a driving force to improve design capability with further scope for cost reductions. For example, in the low voltage (LV) sector (< lkV) vacuum interrupters are available at costs that are much higher than air break switches. Similarly, in the high voltage (HV) sector (52kV les Ur les 145kV) no efficient and cost effective designs are available, and in addition, radiation related safety concerns must be considered. This paper explores the existing switchgear portfolio in LV, MV and HV segments, corresponding demand and emerging market needs for vacuum interrupters and explores areas where the technology needs to be developed and new products brought to market