A Three-Phase Hybrid Multilevel Inverter With Enhanced Pulse-Width Modulation Strategy

• Published in: IEEE transactions on power electronics Vol. 38; no. 4; pp. 4714 - 4726
• Main Authors: Elias, Mohamad Fathi Mohamad, Abd Rahim, Nasrudin, Rosli, Nur Farhana
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.04.2023; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Circuits; Dynamic response; Electric potential; Full-bridge; half-bridge; hybrid multilevel inverter (MLI); Hybrid power systems; Inverters; Modulation; Principles; Pulse duration modulation; Resonant frequencies; Signal generation; Switches; Switching circuits; T-type inverter; Topology; unfolder circuit; Voltage
• DOI: 10.1109/TPEL.2022.3228546
• ISSN: 0885-8993

This article presents a three-phase hybrid multilevel inverter (MLI) with enhanced pulsewidth modulation (PWM) strategy. The proposed hybrid MLI is developed based on the series connection of half-bridge and full-bridge for its level generation together with the T-type inverter for its polarity generation. The level and polarity generation circuits operate at high and fundamental frequencies respectively. An enhanced PWM strategy has been proposed to reduce the computational complexity and solve the high-frequency switching transitions issue in the existing hybrid MLI modulation method. The proposed MLI can produce 11 levels of line output voltage with reduced dc sources requirement. The detailed analyses which have been performed include the circuit configuration, operating principles and modeling, PWM signals generation, output voltage characteristics, dynamic response, harmonics content, power loss analysis and voltage stress of power switches. The results obtained from simulation and experiments verified the operating principle and functionality of the proposed hybrid MLI.