Characterization of phase adjustment of frequency in a series resonant converter with pulse-width regulation

Annotation: The article considers an isolated serial resonant converter with pulse-width regulation. It is established that the conditions for ensuring the switching of transistors at zero voltage (ZVS) are different when regulated by an inverter and a rectifier. It is shown that at zero voltage, only turning on (ZVS-on) or turning off transistors (ZVS-off) can be achieved, which is determined by the sign of the pulse-width regulation angle. It is noted that to ensure the resonant mode, phase-locked loop conversion frequency is necessary. The dependences of the frequency adjustment on the angle of regulation during regulation by the inverter and the rectifier are obtained, it is established that the regulation by the rectifier leads to an increase in the quality factor of the resonant circuit and a decrease in the frequency adjustment, which in this case has a final value determined by the initial quality factor. Moreover, the regulation of the inverter to maintain the resonant mode requires a significantly larger increase in frequency.

Keywords: series resonant converter, dual active bridge, zvs, phase locked loop