Analysis of Conduction and Switching Losses in Three-Phase OHSW Cascaded 9-Level Inverter

This MATLAB simulation framework is designed to accurately quantify conduction and switching losses in a Three-Phase Optimized Harmonic Stepped Waveform (OHSW) cascaded 9-level inverter. The implementation follows a modular subsystem architecture for precise component-level analysis. The first subsystem generates switching functions using OHSW algorithms, typically implemented through logical comparisons and waveform synthesis techniques to create optimized switching patterns. The second subsystem contains the 9-level inverter model, utilizing Simulink power electronics components like IGBTs/diodes with appropriate gate drive logic to simulate multi-level voltage output. Subsystems three and four employ current sensors and measurement blocks to capture load currents and switching device currents respectively, using techniques like current transformers and mathematical computation blocks for accurate current waveform analysis. The fifth subsystem calculates switching losses through mathematical models that integrate voltage-current characteristics during switching transitions, while the sixth subsystem computes conduction losses using device on-state voltage drops and current measurements. Both loss calculation modules incorporate device datasheet parameters and thermal models for realistic loss estimation. This structured approach enables comprehensive performance evaluation of the inverter system, facilitating optimization of switching strategies and device selection for improved efficiency. The modular design allows independent validation of each functional block while maintaining system-level integration for overall loss analysis.