Simulation and Comparison of Three and Nine level Cascaded H-bridge Multilevel Inverter

The multilevel inverter was developed as a solution to increase the converter operating voltage above the voltage limits of classical semiconductors. The function of the multilevel inverter is to synthesize a high voltage waveform from several lower levels of dc voltages. If the switching angle arrangement technique is not selected properly then the total harmonic distortion of voltage output waveform may become unacceptable. In this paper the sinusoidal pulse width modulation (SPWM) control strategy is used to control output voltage. In this paper simulation of single phase three and nine level cascaded H-bridge multilevel inverter is performed in Simulink environment. The comparison of THD values of these inverters is done