Determination of an Asymmetrical Nine Phase Induction Machine Stator and Rotor Inductances Using Winding Function Approach

It is an established fact that the simplest means of parameter extraction of an induction machine (e.g resistances and inductances) can be determined from no load (also known as synchronous) test and locked rotor (short circuit) test. To find the resistance of an electric machine for single or multiple phase induction machine pose no problem, because it is a straight forward approach. However, in multiphase induction machine, with phase number greater than three, such approaches are not utterly sufficient to determine the inductances of the machine. An efficient and easily applicable, analytical approach for calculating the inductance of an asymmetrical multiple phase induction machine based on machine geometric information is presented. An algorithm translated to a Matlab script is developed to numerically evaluate the inductances of any multiphase induction machine using turn function and winding function approach is thoroughly established. Important conclusions regarding the processes to obtain the inductance are presented.