dq0-Modeling of Interior Permanent-Magnet Synchronous Machines for High-Fidelity Model Order Reduction

This paper presents a dq0 flux-linkage based electrical model for permanent-magnet synchronous machines. To obtain the relationship between dq0 flux-linkages and currents, a series of magnetostatic finite-element calculations for various dq0 currents at different rotor positions is carried out. This dataset has then to be inverted to avoid having to derive the flux-linkages in Simulink, thus improving the numerical stability of the model. The model was validated using a 12/10 delta-and star-connected fractional-slot concentrated-winding permanent magnet synchronous machine presenting 3rd-order harmonics in the back-emf. Results show that considering only a fraction of the rated current for the 0-sequence component allows to take circulating currents in a delta-connected machine into account, improving the accuracy of the model compared to a model based on the d-and q-axis alone. Torque and qd0 current waveforms resulting from the presented model are comparable to the ones obtained with finite-element both in terms of average value and harmonic content.