Generalized Hybrid Symmetrical and Asymmetrical Multilevel Inverter Topology with Reduced Number of Switches

Abstract

AbstractMultilevel inverter (MLI) has grown rapidly to achieve higher voltage levels, lesser voltage stress of the power devices, and lesser harmonic distortion of the inverter voltage. This paper presents the analysis of a reduced component hybrid nine-level inverter designed with only three DC sources. The proposed work emphasizes developing a hybrid multilevel inverter using symmetrical and asymmetrical DC sources at the input. The merit of the proposed MLI can efficiently reduce the power of electronic devices to produce the output voltage and generate nine-level using nine IGBTs only. Proposed MLI can be reducing complexity, size, and thus significantly improve inverter cost and performance. Also, a multicarrier-based, level-shifted PWM (LSPWM) method is adopted to generate the desired gate pulses of the IGBT switches using the DSPACE-1103-based controller. A laboratory prototype of the proposed seven-level and nine-level inverters is developed, and the experimental results of the MLIs at RL loading or voltage conditions are present. Further, the inverter losses, efficiency, and the %THD are also analyzed and compared with the other topologies.KeywordsAsymmetrical multilevel inverter (AMLI)Level-shifted pulse width modulation (LS-PWM)%THD