Common-mode voltage elimination of multilevel converters with reduced switching loss using sawtooth-carrier-based PWM

• Main Authors: Chen, Minghao, Niu, Decun, Zhang, Lei, Liu, Ximei
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2023
• Subjects: Engineering::Electrical and electronic engineering; Multilevel Converter; Switching Loss
• Online Access: https://hdl.handle.net/10356/172779
• Institution: Nanyang Technological University

This article proposes an asymmetrical switching pattern to eliminate common-mode voltage (CMV) in multilevel converters while reducing switching loss by rearranging the switching sequence to minimize the number of level-shifts. In contrast to the existing symmetrical switching pattern, this approach achieves CMV elimination without increasing switching loss. To implement this asymmetrical switching pattern, a simple sawtooth-carrier-based pulsewidth modulation scheme is proposed that avoids the need for complicated space vector modulation computation, particularly for high-level converters. The proposed method's effectiveness is demonstrated through simulations and experimental results for the three-phase cascaded H-bridge converter and boost seven-level active neutral-point-clamped converter.