Multi-phase Synchronous Motors: POG Modeling and Optimal Shaping of the Rotor Flux

In the paper the Power-Oriented Graphs (POG) technique is used for modelling m-phase permanent magnet synchronous motors and a study on the rotor flux is given. The POG model of the considered electrical motor shows its internal structure from a “power” point of view. The dynamic model of the motor is as general as possible and it considers an arbitrary odd number of phases. Generalized orthonormal transformations allow to write the dynamic equations of the system in a very compact form. The rotor flux is analyzed, in particular in order to minimize currents needed for the torque generation. An optimal shape for the rotor flux is presented. The model is finally implemented in Matlab/Simulink and some simulations are carried out.