Dc-link capacitance requirement and noise and vibration reduction in 6/4 switched reluctance machine with sinusoidal bipolar excitation

Although different drive topologies have been developed for switched reluctance machine (SRM), the inherent disadvantages, including high dc-link voltage and current pulsations and low drive efficiency, in addition to relatively high torque ripples and acoustic noise and vibration, have limited their application to many applications. To solve this problem, the SRM may be operated as a synchronous reluctance machine but with concentrate winding, and the vector control strategy can then be employed. Compared with conventional unipolar excitation in SRM, it has the advantages of significant reduction of dc-link capacitance, moreover, lower noise and vibration and higher efficiency are also achieved. In this way, it is possible to replace the electrolytic aluminum capacitors with the film ones, which results in much lower cost and higher reliability of the whole drive system, which is very attractive for many applications. Experimental results on a prototype 6/4 SRM validate the effectiveness of sinusoidal bipolar excitation.