Influence of design data of induction motor on effects of cage asymmetry

The paper presents results of analysis of influence of chosen parameters of induction cage motor on the component (1-2s)f0 in stator currents, which is commonly used for diagnosis of cage condition. The investigation concentrates on the influence of commonly available motor data such as pole-pair and rotor slot numbers, respectively, but also on relationships between resistances of cage bars and end rings. A reduced model of motor with a faulty cage is used, in which cage faults are represented by asymmetry coefficients of a cage. The main intention of the paper is to provide engineers with simple estimates of effects due to cage faults for various motors given limited information.