An on-line harmonics elimination PWM scheme for three-phase voltage source inverter using quadratic curve fitting

An on-line harmonic elimination PWM (HEPWM) scheme for three-phase voltage source inverter is proposed. It is based on quadratic curve fitting of the trajectories of the exact HEPWM angles. The main advantage of the technique is that it can be efficiently implemented using a simple low cost microprocessor. An outline to obtain the approximate HEPWM switching angles is presented. To check the accuracy of the method, an error analysis is carried out. The scheme is validated by experimental results.