# A New Method for Elimination of Zero-Sequence Voltage in Dual Three-Level Inverter Fed Open-End Winding Induction Motors

• Geng, Yi-Wen (School of Information and Electrical Engineering, China University of Mining and Technology) ;
• Wei, Chen-Xi (School of Information and Electrical Engineering, China University of Mining and Technology) ;
• Chen, Rui-Cheng (School of Information and Electrical Engineering, China University of Mining and Technology) ;
• Wang, Liang (School of Information and Electrical Engineering, China University of Mining and Technology) ;
• Xu, Jia-Bin (School of Information and Electrical Engineering, China University of Mining and Technology) ;
• Hao, Shuang-Cheng (School of Information and Electrical Engineering, China University of Mining and Technology)
• Accepted : 2016.09.07
• Published : 2017.01.20

#### Abstract

Due to the excessive zero-sequence voltage in dual three-level inverter fed open-end winding induction motor systems, zero-sequence circumfluence which is harmful to switching devices and insulation is then formed when operating in a single DC voltage source supplying mode. Traditionally, it is the mean value instead of instantaneous value of the zero-sequence voltage that is eliminated, through adjusting the durations of the operating vectors. A new strategy is proposed for zero-sequence voltage elimination, which utilizes unified voltage modulation and a decoupled SVPWM strategy to achieve two same-sized equivalent vectors for an angle of $120^{\circ}$, generated by two inverters independently. Both simulation and experimental results have verified its efficiency in the instantaneous value elimination of zero-sequence voltage.

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