Implementation of SVPWM based Multilevel Three Phase Inverter to Reduce THD

Abstract

The Multilevel inverter has gained great attention from the academia and industry due to its increased number of applications in the power sector. However, effective control of semiconductor switches plays very crucial role in the output of inverter, as any wrong execution of two switching patterns simultaneously may result in short circuit. Moreover, high frequency switching of these switches cause power losses and harmonic distortion. Soft switching techniques are used to reduce switching losses and consequently improve Total Harmonic Distortion (THD). In this research work, Space Vector Pulse Width Modulation (SVPWM) technique is employed to improve the switching loss and THD of multilevel three phase inverter and consequently increase the efficiency of system. The performance has been investigated in terms of THD, fundamental output line voltage and output line current for multiple resistive loads. The results show that proposed technique has successfully controlled the output in both scenarios and reduced the THD to an acceptable limit of 2.91 %Thus, the results validate that SVPWM is an effective technique for multilevel inverters.