Quasi-resonant converter

Switching converters are broadly classified into resonant and non-resonant types. A resonant converter controls switching operation using sinusoidal AC voltage or current. In contrast, a non-resonant converter controls the switching operation by pulse-width modulation. A quasi-resonant converter combines the advantages of both resonant and non-resonant converters to reduce switching losses. It controls the switching operation using a pseudo-sine wave formed by combining distorted and trapezoidal waveforms. Quasi-resonant converters are used in applications such as auxiliary power supplies for power conversion systems because they offer high efficiency under stable load conditions.