• R.Ravi
• J.Srinivas Rao

Multilevel voltage source converters are emerging as a new breed of power converter options for high-power applications. The multilevel voltage source converters typically synthesize the staircase voltage wave from several levels of dc capacitor voltages. One of the major limitations of the multilevel Converters is the voltage unbalance between different levels. The techniques to balance the voltage between different levels normally involve voltage clamping or capacitor charge control. There are several ways of implementing voltage balance in multilevel converters. This paper presents a three-phase multistring multilevel inverter coupled to induction machine drive for evaluating the performance characteristics of drive application. The multilevel topology consists of several H-bridge cells connected in series, each one connected to a string. The simplified multilevel inverter requires only six active switches instead of the eight required in the conventional cascaded H-bridge multilevel inverter. In addition, two active switches are operated at the line frequency. The studied multistring inverter topology offers strong advantages such as improved output waveforms, smaller filter size, and lower electromagnetic interference and total harmonics distortion. Finally an asymmetrical configuration is proposed with this we are getting seven levels with six switches.

DC/AC power conversion, multilevel inverter, induction machine drive

"A Novel Three Phase Multi-String Multilevel Inverter Topology Applied to Induction Machine Drive", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.3, Issue 9, page no.84-88, September-2016, Available :http://www.jetir.org/papers/JETIR1609015.pdf

"A Novel Three Phase Multi-String Multilevel Inverter Topology Applied to Induction Machine Drive", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.3, Issue 9, page no. pp84-88, September-2016, Available at : http://www.jetir.org/papers/JETIR1609015.pdf