THE USE OF SERRAPHIL FUNCTIONS IN THE PERFORMANCE CALCULATION OF ASYNCHRONOUS MACHINES

Abstract

Parasitic torques in asynchronous machines are caused by the variation of the air gap permeance due to the slots and by the m.m.f. harmonics produced by the distributed windings. In practice these torques are calculated by means of finite Fourier series. By the help of serraphil and serramorph functions the influence of the slots and the distributed windings on the air gap field and the dependence of the elements from the rotor position in the torque matrix can be described in a closed form. In this way the resolution of the voltage and mechanical equations by computer become relatively simple. It is possible to take the saturation into consideration, too.