Application of pulse frequency modulation for voltage frequency control of inverters

Abstract

An inverter is designed and implemented, that applies pulse frequency modulation(PFM) in order to shape a constant DC voltage into an AC voltage with controllable magnitude and frequency. The authors investigated the effect of different parameters on the harmonic content of the generated PFM pattern, such as the effect of the ratio of carrier to reference frequency, modulation depth and pulse width using a software program constructed to simulate PFM patterns and calculate the corresponding harmonic content. According to these investigations an appropriate decision is taken about the suitable parameters of the PFM applied to the inverter.