Table of Contents
Advances in Power Electronics
Volume 2012 (2012), Article ID 327157, 12 pages
http://dx.doi.org/10.1155/2012/327157
Research Article

Carrier-Based Common Mode Voltage Control Techniques in Three-Level Diode-Clamped Inverter

1Electrical Engineering Department, SATI, Vidisha 464001, India
2Electrical Engineering Department, MANIT, Bhopal 462051, India
3Electrical Engineering Department, IIT, Uttaranchal, Roorkee 247667, India

Received 31 May 2012; Revised 27 July 2012; Accepted 29 July 2012

Academic Editor: Francesco Profumo

Copyright © 2012 Pradyumn Chaturvedi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Switching converters are used in electric drive applications to produce variable voltage, variable frequency supply which generates harmful large dv/dt and high-frequency common mode voltages (CMV). Multilevel inverters generate lower CMV as compared to conventional two-level inverters. This paper presents simple carrier-based technique to control the common mode voltages in multilevel inverters using different structures of sine-triangle comparison method such as phase disposition (PD), phase opposition disposition (POD) by adding common mode voltage offset signal to actual reference voltage signal. This paper also presented the method to optimize the magnitude of this offset signal to reduce CMV and total harmonic distortion in inverter output voltage. The presented techniques give comparable performance as obtained in complex space vector-based control strategy, in terms of number of commutations, magnitude, and rate of change of CMV and harmonic profile of inverter output voltage. Simulation and experimental results presented confirm the effectiveness of the proposed techniques to control the common mode voltages.