A Seven-Level Converter Using a Combination of Staircase and PWM Switching Methods


In this paper, a new method is proposed for switching a multilevel converter. In this converter two H-Bridge cells are connected in series with each phase of a three-phase diode-clamped converter. Operation of main converter and one of H-Bridge cells is based on the staircase switching method. Switching angles of the three phase converter and one of the H-Bridges are selected in a way to generate the fundamental harmonic of the phase and eliminate the fifth and seventh harmonics. However, the switching pattern of the second H-Bridge cell is based on PWM method. This cell generates the remaining parts of the desired sinusoidal waveform. Combination of these converters and their switching methods results in an output waveform with low harmonics. Simulation and experimental results agree with each other and show the proper operation of the proposed method.

Meeting Name

36th Annual Conference of the IEEE Industrial Electronics Society (2010: Nov. 7-10, Glendale, AZ)


Electrical and Computer Engineering

Keywords and Phrases

Diode-Clamped; Fundamental Harmonic; H-Bridge Cells; H-Bridges; Multilevel Converter; Output Waveform; PWM Switching; Seven-Level; Sinusoidal Waveforms; Switching Angles; Switching Methods; Switching Patterns; Three-Phase Converter; Electric Inverters; Harmonic Analysis; Industrial Electronics; Stairs; Voltage Control; Switching

International Standard Book Number (ISBN)


International Standard Serial Number (ISSN)


Document Type

Article - Conference proceedings

Document Version


File Type





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

Publication Date

01 Nov 2010