Patent attributes
A power converter including a transformer, a resonant circuit including the transformer and a resonant capacitor having a characteristic resonant frequency and period, and output circuitry connected to the transformer for delivering a rectified output voltage to a load. Primary switches drive the resonant circuit, a clamp switch is connected to shunt the resonant capacitor, and a switch controller operates the primary switches and the clamp switch in a series of converter operating cycles. The converter operating cycles include power transfer intervals including resonant intervals during which a resonant current at the characteristic resonant frequency flows through a winding of the transformer; and a clamp interval during which the clamp switch provides a low impedance shunt across the resonant capacitor holding the resonant capacitor at a voltage at or near zero volts. The operating cycles may also include energy recycling intervals for charging and discharging capacitances within the converter.
