Five-Level Multiple-Pole PWM AC-AC Converters with Reduced Components Count

• Main Authors: Lim, Ziyou, Ooi, Gabriel Heo Peng, Maswood, Ali Iftekhar
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2016
• Subjects: Five-level (5L) multiple-pole converter; reduce number of semiconductor devices; transformerless drive
• Online Access: https://hdl.handle.net/10356/81575; http://hdl.handle.net/10220/39553
• Institution: Nanyang Technological University

This paper proposes novel multilevel AC/DC/AC converters with reduced number of semiconductor devices to achieve light weight, efficiency and better input current quality. The proposed three-phase front-end bidirectional five-level (5L) rectifier and rear-end 5L-inverter are constructed based on multiple-pole multilevel diode-clamped approach (M2DCC), which consist a total number of 24 diode components clamped. Based on M2DCC concept, the number of switching devices can be further reduced to construct a new unidirectional front-end rectifier (M2SCR). Comparative studies are conducted to analyze the performances of the two proposed front-end rectifiers with supportive mathematical derivations. Experimental prototypes have proven the feasibility of the proposed AC/DC/AC configurations. Results obtained show that low current harmonic distortions of 5% and high power factor of 0.99 are achieved with small input inductors despite of low switching frequency operation at 1 kHz.