Smooth electromagnetic torque in nonsinusoidal permanent magnet AC machines

This work presents a vectorial model for nonsinusoidal permanent magnet AC synchronous machines (permanent magnet "brushless" motor). With this model it is possible to have a direct control of the machine electromagnetic torque and, consequently, it is possible to reduce torque ripple, reducing noise and increasing performance. A nonsinusoidal machine was driven by a six-step inverter and by a nonsinusoidal vectorial control. The results evidence the reduction of machine electromagnetic torque ripple. Also, a commercial nonsinusoidal PM machine (driven by nonsinusoidal vectorial control) was compared with a sinusoidal PM machine (driven by sinusoidal vectorial control). It is shown the differences between these two systems.