Pulsating Torque Analysis of PMSM Driven by Dual Mode Inverter Control in Wide Constant Power Speed Range

The scope of this work is the analysis of pulsating torque in Permanent Synchronous Machine (PMSM) driven by Dual Mode Inverter Control (DMIC) in wide Constant Power Speed Range (CPSR). The operation principle of DMIC driving PMSM in a CPSR is briefly described. In the sequence, analytical results of the three-phase currents in the stationary reference frame, as well as the dq currents in the rotating reference frame are given. The pulsating torque resulting of the DMIC strategy is then addressed through Fourier analysis showing the harmonic content of the id and iq currents. With this analysis, is possible to observe how the pulsating torque behaves as speed increases. The results are relevant to help engineers to decide to what application DMIC may be used, and to estimate the pulsating torque effect at speed depending on the load/machine parameters.