POWER QUALITY ENHANCEMENT OF H-BRIDGE INDIRECT OUTPUT VOLTAGE BY CHANGING TIME DISTRIBUTION OF VOLTAGE STATUS 0 AND DIFFERENT 0

This article proposes a plan to improve the quality of the output AC voltage of the H-bridge inverter based on the change of the law of distribution of zero and non-zero voltage states of the inverter when controlling the H-bridge inverter. The results were surveyed, analyzed, compared, and evaluated by simulation model on Matlab-Simulink software. In which the fundamental harmonic level index and the total harmonic distortion (THD) are used to compare, analyze and evaluate the quality of H-bridge inverter output voltages in different switching modes such as pulse width modulation according to sine law (sinPWM), pulse width adjustment (SIR) and the proposed improved pulse width modulation law. The results show that the H-bridge inverter output voltage form with improved sequential switching law gives better quality than the original. This result has practical significance in the research and design of power conversion circuits for AC power transmission systems.