Implementation of real-time PWM on STM32F103 for the control of five-level cascaded H-Bridge multilevel inverter

Abstract

This thesis deals with the control of a five-level cascaded H-Bridge multilevel inverter. It also offers a real-time implementation of various pulse width modulation (PWM) techniques. These include level shifted (LS-PWM) and phase shifted (PS-PWM) modulations, which are implemented on a microcontroller. A comparative study is carried out between these proposed techniques, including the conventional control technique (full wave). Then, simulations are carried out in a MATLAB / Simulink environment. Subsequently, a parametric analysis is carried out in order to study the effect of certain parameters such as the modulation index, the switching frequency, etc. The asynchronous machine is used as a load for the output of the inverter whose variation of currents, torque and speed is presented. On a practical level, experiments are carried out in order to validate the simulation results. The microcontroller used is an STM32F103 attached to a nucleo board, and it is used to generate the gate control signals of the inverter switches.