Fibonacci Series for Hybrid Symmetrical Multilevel Inverter Topology Using Different PWM Strategies

Abstract

Multilevel inverters are suggested to obtain high superiority output voltage. In this paper, a new hybrid configuration is proposed, obtained by cascading one four switches H-bridge cell with a family of multilevel inverters. In addition, by the use of specific sequence for value of DC sources named Fibonacci series, new topology of proposed inverter is introduced. Main advantages are that planned inverter has least Peak Inverse Voltage (PIV) than other conventional multilevel converters in both symmetric and asymmetric modes. Also, this topology doubles the number of output levels using only one cascaded four switches H-bridge cell. This paper proposes a 7-level Fibonacci series for new hybrid symmetrical multilevel inverter. This proposed multilevel inverter topology here is implemented in single-phase with different pulse width modulation (PWM) techniques, which requires less number of components, less carrier signals and gate drive circuit as compared to conventional multilevel inverters. A multicarrier PWM technique is used for multilevel inverter topology to generate 7-level output voltage. Finally simulation results of a 7-level multi-level inverter topology are carried out using MATLAB/Simulink R2010a software version.

Keywords: Multi-level inverter (MLI); Pulse Width Modulation (PWM) techniques; Peak Inverse Voltage (PIV) and Fibonacci series