Impact of Amperage Creep on Potroom Busbars and Electrical Insulation: Thermal-Electrical Aspects

Busbars electrical insulation is a critical aspect of aluminium smelters potrooms electrical safety. With amperage creep, busbars are typically running hotter than they were at start-up. The long-term reliability of busbars and the integrity of insulating materials is therefore of concern. To assist smelters evaluate the performance of the busbars systems under realistic operating conditions, a methodology was developed using ANSYS (TM)-based numerical simulation, laboratory testing and in situ measurements. This approach has been validated on different pot technologies and smelters. A realistic test case based on a demonstration busbar system is presented and the typical impact of line current, ambient temperature and selected operational procedures on thermal-electrical performance and reliability is discussed.