Abstract: Methods and systems for controlling an output voltage of a resonant converter during a light load condition. One such method includes generating a normalised conduction time of the resonant converter that varies inversely with a switching frequency of the resonant converter by continuing to operate the resonant converter in a Pulse Frequency Modulation mode at a low switching frequency that is similar to the resonant frequency. The method also includes controlling a power level delivered to a secondary winding of a transformer positioned between a resonant tank and an output rectifier of the resonant converter by regulating the normalised conduction time, where the delivered power level is variable based on load conditions. The method further includes generating an output voltage using the output rectifier wherein the magnitude of the output voltage corresponds to the power level delivered to the secondary winding.

Abstract: Methods and systems for controlling an output voltage of a resonant converter during a light load condition. One such method includes generating a normalised conduction time of the resonant converter that varies inversely with a switching frequency of the resonant converter by continuing to operate the resonant converter in a Pulse Frequency Modulation mode at a low switching frequency that is similar to the resonant frequency. The method also includes controlling a power level delivered to a secondary winding of a transformer positioned between a resonant tank and an output rectifier of the resonant converter by regulating the normalised conduction time, where the delivered power level is variable based on load conditions. The method further includes generating an output voltage using the output rectifier wherein the magnitude of the output voltage corresponds to the power level delivered to the secondary winding.

Abstract: A single conversion stage bidirectional soft-switched AC/AC power converter system is capable of converting power in both directions between high- and low-voltage sources. The system has substantially loss-less switching and regulated output in both directions of power transfer. The semiconductor and electro-magnetic components of the system provide both output regulation and soft switching in both the step-up and the step-down directions of power conversion. The commonality of components between the two directions of power transfer reduces total component count, cost and volume, and enhances power conversion efficiency. An associated method of power transfer employs structural symmetry in a resonant circuit of the system to ensure high efficiency line power transfer in both directions.

Abstract: A resonant, bi-directional, DC to DC voltage converter with loss-less (soft) switching having regulated output and capable of converting power between two, high-potential and low-potential DC voltage sources. The converter's semiconductor and magnetic components provide both, output regulation and soft switching in both (step-down and step-up) directions of power conversion which reduces total component count, cost and volume and enhances power conversion efficiency.

Abstract: A resonant, bi-directional, DC to DC voltage converter with loss-less (soft) switching having regulated output and capable of converting power between two, high-potential and low-potential DC voltage sources. The converter's semiconductor and magnetic components provide both, output regulation and soft switching in both (step-down and step-up) directions of power conversion which reduces total component count, cost and volume and enhances power conversion efficiency.