Variable sampling frequency PWM waveforms

A method for online generation of single-phase near optimal pulse width modulated (PWM) waveforms is described. This method is based on using variable sampling periods in sampled PWM. Simulation results are presented for a single-phase full-bridge inverter feeding a resistive-inductive (R-L) load. Total harmonic distortions of current waveforms are found to be less, compared to PWM with constant sampling period.