Slip Determination considering Mismatched Fundamental and Harmonic Rotor Resistance for Multiphase Induction Machines under Non Sinusoidal Supply

In this paper, the slip frequency calculation is proposed to provide fast and accurate estimation of rotor resistance for multiphase induction machine (IM) under non sinusoidal supply in the flux-oriented frame. Contrary to traditional methods, the multiphase induction machine for this adaptation procedure is based on rotor flux-oriented frame (RFOC) for the fundamental plane and air gap flux-oriented frame (AFOC) for the harmonic plane in order to limit the core saturation. The constraint of third harmonic slip for achieving synchronized and aligned control of magnetic field distribution is updated on the basis of fundamental slip. Harmonic air gap filed oriented rotor resistance is tuned by ensuring the zero field orientation condition for the air gap flux and the harmonic injection currents are updated accordingly. Simulation results verifies the rotor resistances convergence process for multiple planes and for large variation of load changes, steady state performance can be achieved.