Comparative influence of adjacent and non-adjacent broken rotor bars on the induction motor diagnosis through MCSA and ZSC methods

It has been reported in the past that, the non-adjacent broken rotor bars in three-phase induction motors can influence the diagnostic ability of the line current frequency spectrum. In this paper, the traditional line and zero-sequence current broken rotor bar fault signatures are studied for different broken rotor bar fault configurations. More specifically, the cases to be investigated are healthy, one broken bar, two adjacent broken bars and two non-adjacent broken bars. The results shown in this paper lead to the conclusion that the zero-sequence current presents several advantages compared to the traditional line current-based method. This can be especially useful in industrial motors where there is the possibility of measuring these currents since it can help to avoid some false negative cases obtained with the conventional Motor Current Signature Analysis.