A Voltage-Boosting Seven-Level Switched Capacitor Multilevel Inverter With Reduced Device Count
V S Prasadarao K, Sankar Peddapati, Balram Kumar
Abstract
This article introduces a novel switched capacitor multilevel inverter (SCMLI) that offers a minimum number of components. The inverter generates a seven-level output waveform across the load by utilizing a single dc source, two capacitors with a rating of half the input voltage, and nine semiconductor switches. The key features of this proposed SCMLI include voltage boosting ability (up to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1.5\times $ </tex-math></inline-formula> the input voltage), reduced device count, absence of bidirectional switches, self-balancing of capacitors, and lower total standing voltage (TSV). This article presents a detailed analysis covering the operating principles, capacitor voltage balancing, and control strategy. Comprehensive evaluations, such as power loss, efficiency analysis, cost function per level (CF/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\text{N}}_{l}$ </tex-math></inline-formula> ), and switching device power (SDP) ratings, are also provided. The steady-state and dynamic performance of the proposed topology (PT) are verified through simulation studies using MATLAB/SIMULINK software, and experimental studies validate the results. Furthermore, this article includes a comparative study between the proposed SCMLI and other recently introduced multilevel inverters (MLIs). Finally, the performance of the PT for single-stage grid-connected photovoltaic (PV) system has been verified and corresponding results are presented.