Low Carrier Ratio Control for Dual Stator-Winding Induction Generator with Selective Harmonic Elimination Pulsewidth Modulation

With the development of more/all electric aircrafts, variable frequency AC (VFAC) generation systems become popular. Dual stator-winding induction generators (DWIG) utilized in VFAC systems have the feature of the high fundamental frequency. However, the switching frequency of high power devices does not exceed 5 kHz in general, which makes carrier ratio lower. Thus, how to ensure the quality of the output voltage under the low carrier ratio condition becomes the focus of the study. In this paper, a novel low carrier ratio control method is proposed to improve the quality of the output voltage. In this method, the selective harmonic elimination pulsewidth modulation (SHEPWM) is adopted and the carrier ratio changes depending on different fundamental frequency ranges. The switching losses are limited while the quality of the output voltage remains good. Simulation and experimental results prove this method is effective.