The optimum waveform parameters of pulse positions and pulse widths for voltage source inverters with fluctuating input voltage are proposed. Eight types of novel modulation schemes for synthesizing the optimum low-distortion output waveforms, of which the harmonic spectra and the peak fundamental value are almost insensitive to the input voltage fluctuation, with a minimum voltampere rating of inverter input filter, are described. For fluctuating inverter input voltage with insufficient filtering, the type-VII and the alternative type-Ill modulation schemes are found to be especially suitable for practical implementation. Detailed descriptions of the suggested circuits with dual feedback control for implementing two such modulation schemes are given. A novel peak-value detector that can rapidly produce the peak value of the inverter output voltage with a minimum time constant is also proposed. The theoretical results of the proposed approaches with open-loop self-regulating property are experimentally verified and compared with the conventional triangulation method.
All Science Journal Classification (ASJC) codes