On the theory of 3-phase squirrel-cage induction motors including space harmonics and mutual slotting

Abstract

In this paper general equations for the asynchronous squirrel-cage motor which contain the in- fluence of space harmonics and the mutual slotting are derived by using among others the power-invariant sym- metrical component transformation and a time-dependent transformation with which, under certain circumstances, the rotor-position angle can be removed from the coef- ficient matrix. The developed models implemented in a machine-independent computer program form powerful tools, with which the influence of space harmonics in relation to the geometric data of specific motors can be analyzed for steady-state and transient perfor- mances. Simulations and measurements are presented in a companion paper.