A Hybrid Multilevel Inverter with Both Staircase and PWM Switching Schemes


In this paper, a new method to control multilevel converters is proposed. The considered multilevel converter consists of a three-phase three-level diode-clamped converter (main converter). Two H-bridge cells are then connected in series with each output phase of the main converter. The operation of the main converter and one of the cascading H-bridge cells is based on the staircase switching method. The firing angles of these converters are selected in a way that the dc voltage required for the last H-bridge cell is minimized. The switching pattern of the second H-bridge cell is based on the pulse-width modulation method. This last cell generates the remaining parts of the desired sinusoidal output voltage. The combination of these converters and their switching methods result in an output waveform with low harmonics. Here, a fifteen-level converter is designed based on this approach. Simulation results and laboratory measurements verify the effectiveness of the proposed topology and modulation method.

Meeting Name

2nd Annual IEEE Energy Conversion Congress and Exposition (2010: Sep. 12-16, Atlanta, GA)


Electrical and Computer Engineering

Keywords and Phrases

DC Voltage; Diode-Clamped; Firing Angle; Fundamental Switching; H-Bridge Cell; H-Bridge Cells; Hybrid Multilevel Inverter; Inverter; Laboratory Measurements; Level Converter; Modulation Methods; Multilevel Converter; Multilevel Inverter; Output Phase; Output Waveform; PWM Switching; Simulation Result; Sinusoidal Output; Switching Methods; Switching Patterns; Three-Level; Counting Circuits; Energy Conversion; Modulation; Pulse Width Modulation; Stairs; Switching; Voltage Control; Electric Inverters; Fundamental Switching

International Standard Book Number (ISBN)


International Standard Serial Number (ISSN)

2329-3721; 2329-3748

Document Type

Article - Conference proceedings

Document Version


File Type





© 2010 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Sep 2010