A Modified Single Phase H-Bridge Inverter for High Power Applications with Power Quality Improvement

Abstract

Various multilevel inverter topologies are widely being used for real power exchange, reactive power compensation, harmonic current mitigation on grid and industrial drive applications with fundamental frequency switching mode of gate control. Still so many topologies are being currently developed with reduced number of switches, improved waveform for power quality improvement with fundamental frequency switching and pwm switching gate control mode. This paper presents the performance analysis of modified H-bridge single phase inverter for high voltage and high power applications. The switching method has been selected to operate the inverter at fundamental frequency switching mode of gate control to be free from lower order harmonics. The inverter has the modulation technique with pre calculated switching angles to generate the required fundamental voltage with reduced Total Harmonic Distortion (THD). So, the switching losses have been reduced hence the efficiency is improved with Power Quality (PQ) improvement in voltage-current waveform. The DC input power is feed to the inverter from DC capacitor voltage divider source, contributed to give various dc voltage levels during fundamental frequency switching of different switching combinations for the generation of stepping output voltage. During dynamic load condition, the magnitude of input dc voltage level across each capacitor has not undergone through big swing to feed the power to the load without affecting generated output ac voltage. The performance of the proposed inverter has been analyzed for dynamic reactive load and induction motor. The MATLAB based simulations have been presented to validate the inverter operation for dynamic reactive load and industrial drive applications with pre calculated THD reduced switching conduction angles for PQ improvement in waveform.