On the Electromagnetique Torque Expresion of an Induction Machine Asymmetrical Supplied

Abstract

If a symmetrical induction machine operates on an asymmetrical voltage system an asymmetrical system quantities (voltages, currents, fluxes) occurs. The same thing happens if the power supply is symmetrical but the induction machine is asymmetrical, either by construction or by fault. The currents and fluxes hodograph is no longer circular but elliptical. As the final result of the electromagnetic phenomena the torque developed by the induction machine is affected. Even in steady state the electromagnetic torque is no longer constant. A ripple i.e. an alternative component overlaps its average value. The paper aims to determine a usable analytical expression that clearly indicates the causes that influence the value of the sinusoidal component of the torque: the asymmetric supply or the failure of the induction machine.