Generation of optimal switching pattern for single-phase inverter

In this paper, we propose a preliminary study on a new optimal pulse width modulation (PWM) strategy to encode an oversampled sinusoidal waveform. The optimal encoded signal for single-phase inverter drives is obtained through minimization of spurious harmonics content within a certain band, subject to the constraint of finite time resolution of the encoded signal switching instants. This additional constraint makes impossible to analyze the spectral properties of the switching process with the analytical tools of the traditional programmed PWM techniques. Hence, we developed a new minimization method, which inherits from the traditional ones the harmonic elimination optimality criterion, and we give a detailed description of the novel encoding scheme. In particular, its performance will be compared with respect of traditional modulating schemes for some topic cases, and its advantages and disadvantages will be thoroughly highlighted.