Analysis of high performance multilevel converter fed Permanent Magnet Synchronous Motor drive

Multilevel converter technology has emerged recently as a very important alternative in the area of high-power medium-voltage energy control. The advantages of multilevel converters are lower switching losses, improved power quality, better electromagnetic compatibility, and higher voltage capability. Several topologies for multilevel inverters have been proposed over the years; the most popular cascaded H-bridge apart from other multilevel inverters is the capability of utilizing different dc voltages on the individual H-bridge cells which results in splitting the power conversion amongst higher-voltage lower-frequency and lower-voltage higher-frequency inverters. In this paper Sinusoidal and third harmonic injected carrier based PWM technique i.e. phase shifted carrier PWM (PSCPWM) and level shifted carrier PWM (LSCPWM) are implemented and analysed the THD levels for different values of modulation index and switching frequency. In level shifted carrier PWM, in phase disposition (IPD), alternative phase opposite disposition (APOD) and phase opposite disposition (POD) modulating technique is analysed using MATLAB/ SIMULINK. Finally better modulating technique is applied to drive the five level cascaded-H Bridge fed Permanent Magnet Synchronous Motor drive