HARMONC REDUCTION IN SINGLE PHASE INVERTER USING H-INFINITY (H∞)TECHNIQUE

This project focus on modeling of single phase inverter and describes that total harmonic distortion can be reduced considerably using H- infinity technique. An inverter is a circuit that converts DC sources to AC sources. H- Infinity technique that use as a way to decrease total harmonic distortion in inverter circuit.  A H infinity robust controller for a sinusoidal- Pulse- Width modulation (SPWM)inverter is designed. The sinusoidal-phase PWM inverter generates an AC sinusoidal output from a DC link voltage. Robustness to of the output waveform against load variations and minimum Total Harmonic Distortion (THD) are the main goals in this design. The importance of this design methodology results from the changes in the inverter's transfer function as affected by load variations. So it is necessary to use a robust controller such as H-infinity. In this work, an output feedback controller is designed based on H-infinity control theory to reduce the influence of parameter perturbation on the performance and robustness of active filters.  Here we are going to implement PID controller  in PIC microcontroller,  At the end of the project, THD of the inverter output is greatly reduced.