Real time analysis and simulation of five level grid connected H-bridge inverter using FPGA based controller

Abstract

In this paper FPGA based controller is developed for a cascaded 5-level H-bridge inverter inject active power to the grid through renewable sources. It reduces stress level on the different switches. Harmonic distortion and EMI in H-bridge Inverter cause by the different switching of power electronic devices. A capacitor, boost converter, three phase full bridge inverter and a filter add up to form a total five level inverter. The renewable energy source act as a input to the boost converter. The boost converter output is supplied to the capacitor which in turn is connected to the full bridge inverter. The switching action of the switches in five level H-bridge inverter is according to the controller action to give a five level AC voltage. The five level inverter output current is controlled to get the sinusoidal current in phase with the voltage of the utility in order to inject power in the grid. A prototype is developed so as to verify the performance of the cascaded five level H-bridge inverter with a grid connected renewable energy system. The results of the experiment show that the system gives the expected performance.