A Single-Phase Cascaded H-Bridge Multilevel Inverter With Voltage Boost Ability: Modulation and Analysis

In this work, a single-phase boost-type cascaded H-Bridge inverter is considered to analyze its performance under various pulse width modulation techniques as well as the loss assessment evaluation at a variable modulation index and power factor loads. The family of split source inverters (SSI) suffers from diode commutation due to input diodes. The absence of input diodes in this impedance network-based boost-type inverter topology increases the efficiency and allows reverse operation. The phenomena of self-voltage balance is an added attribute to the boost-type inverter that eliminates complex capacitor voltage control at all power factor loads. The loss and reliability assessment is provided at variable modulation index and power factor angle using rain flow algorithm analysis. A simulation analysis is provided to validate the mathematical assessment followed by an experimental evaluation using a laboratory prototype with a Spartan-6-based FPGA controller. Different case studies are analyzed and their results are presented to verify the optimum performance of the topology.