Abstract: A LLC bidirectional resonant converter comprising: a resonant tank, a first switching circuit connected to the resonant tank via first power conduits, a second switching circuit connected to the resonant tank via second power conduits, a switching element, and at least one switchable inductive element which is arranged by the switching element to be in parallel across the second power conduits when operating in a first mode of operation and arranged by the switching element to be in parallel across the first power conduits when operating in a second mode of operation.

Abstract: A resonant converter including: a resonant tank, a switching circuit that connects the resonant tank to a power supply according to a first switching sequence, a synchronous rectifier circuit that supplies power to an output, wherein the rectifier circuit is switched according to a second switching sequence, and a phase delay module arranged to delay the second switching sequence with respect to the first switching sequence to achieve a desired power output, and a method of controlling the same.

Abstract: A three phase full resonant cyclo-converter suitable for converting a three phase AC supply to a DC output. In one embodiment the cyclo-converter consists of two half bridge cyclo-converters driving a resonant circuit. The main switching sequence of the cyclo-converter may consist of a switching sequence in which the phases of a three phase supply are switched in a repeating sequence from the largest to the smallest absolute voltage value of the supply phases.

Abstract: A three-phase resonant cyclo-converter, the cyclo-converter comprising a feed forward control module arranged to develop a feed forward signal for controlling a switching frequency of the cyclo-converter dependent on conditions of a power supply arranged to provide power to the cyclo-converter.

Abstract: A three-phase resonant cyclo-converter comprising a power control module, wherein the power control module is arranged to develop a plurality of repeating switching periods within a cycle, the power control module further arranged to: control the length of a first switching period in the cycle to adjust the power flow, and control the relative length of two or more further switching periods in the cycle to adjust the power factor, wherein the relative length is controlled based on a cross-product of voltage and current values associated with the further switching periods.

Abstract: A three-phase resonant cyclo-converter including a closed loop control module for controlling the switching frequency of the cyclo-converter, the closed loop control module including: a voltage signal development module arranged to develop a voltage signal representative of a voltage output waveform of the cyclo-converter, a storage module arranged to accumulate voltage signal values for phase portions of the voltage output waveform, where the voltage signal values are based on a voltage error signal and accumulated historical voltage signal values for the same corresponding phase portions, and a switching frequency control module arranged to develop a switching frequency control signal to control the switching frequency of the cyclo-converter based on the accumulated voltage signal values for corresponding phase portions of the voltage output waveform, and a proportional voltage signal based on a difference between the developed voltage signal and a reference voltage signal.

Abstract: A power converter providing required hold up for a primary converter, particularly a cycloconverter, without the required hold up capacity by an auxiliary converter including storage capacitors having the requisite capacity. The auxiliary converter may be isolated from the primary converter during normal operation and switched in during power supply discontinuities. The storage capacitors may be charged via a voltage step up circuit to achieve improved charge utilization. The storage capacitors may be charged via a charge path independent of the auxiliary converter output path so that the storage capacitor charging rate may be set independently.

Abstract: A power factor corrected switched mode power supply including a phase shifter that senses the mains frequency and phase shifts it to produce a phase shifted signal which modulates the switching signal supplied to the switches based on the phase shifted signal. The rate of change of the frequency of the switching signal may be controlled to be greatest in regions of greatest power transfer.

Abstract: A power factor correction booster circuit for connection to an alternating current (AC) power source including a first circuit portion arranged to be active over a first AC half cycle of the power source, the first circuit portion including: a first AC input node in connection with a source node of a first power transistor, a first node of an inductive element in connection with a drain node of the first power transistor, a second node of the inductive element in connection with a drain node of a second power transistor, a second AC input node in connection with a source node of the second power transistor, an anode of a first semiconductor diode element in connection with the second node of the inductive element, a cathode of the first semiconductor diode element in connection with a first node of a first output capacitor element, and a second node of the first output capacitor element in connection with the second AC input node, wherein the first and second power transistors are controllable to switch the f

Abstract: A three phase full resonant cyclo-converter suitable for converting a three phase AC supply to a DC output. In one embodiment the cycloconverter controls switching frequency to control converter output and adjusts phase on times for power factor correction. A switching sequence is employed which provides resonant switching to reduce losses and component ratings. The converter provides high conversion efficiency with a simple power component design.

Abstract: A three-phase resonant cyclo-converter comprising a power control module, wherein the power control module is arranged to develop a plurality of repeating switching periods within a cycle, the power control module further arranged to: control the length of a first switching period in the cycle to adjust the power flow, and control the relative length of two or more further switching periods in the cycle to adjust the power factor, wherein the relative length is controlled based on a cross-product of voltage and current values associated with the further switching periods.

Abstract: A three-phase resonant cyclo-converter including a closed loop control module for controlling the switching frequency of the cyclo-converter, the closed loop control module including: a voltage signal development module arranged to develop a voltage signal representative of a voltage output waveform of the cyclo-converter, a storage module arranged to accumulate voltage signal values for phase portions of the voltage output waveform, where the voltage signal values are based on a voltage error signal and accumulated historical voltage signal values for the same corresponding phase portions, and a switching frequency control module arranged to develop a switching frequency control signal to control the switching frequency of the cyclo-converter based on the accumulated voltage signal values for corresponding phase portions of the voltage output waveform, and a proportional voltage signal based on a difference between the developed voltage signal and a reference voltage signal.

Abstract: A switched mode power supply allowing a half bridge converter to be use alone or in combination with another converter to form a full bridge converter. A common controller may be used for either half bridge or full bridge configurations. The modular approach simplifies design for a range of power supplies and reduces costs.

Abstract: A power converter providing required hold up for a primary converter, particularly a cycloconverter, without the required hold up capacity by an auxiliary converter including storage capacitors having the requisite capacity. The auxiliary converter may be isolated from the primary converter during normal operation and switched in during power supply discontinuities. The storage capacitors may be charged via a voltage step up circuit to achieve improved charge utilization. The storage capacitors may be charged via a charge path independent of the auxiliary converter output path so that the storage capacitor charging rate may be set independently.

Abstract: A power factor correction booster circuit for connection to an alternating current (AC) power source including a first circuit portion arranged to be active over a first AC half cycle of the power source, the first circuit portion including: a first AC input node in connection with a source node of a first power transistor, a first node of an inductive element in connection with a drain node of the first power transistor, a second node of the inductive element in connection with a drain node of a second power transistor, a second AC input node in connection with a source node of the second power transistor, an anode of a first semiconductor diode element in connection with the second node of the inductive element, a cathode of the first semiconductor diode element in connection with a first node of a first output capacitor element, and a second node of the first output capacitor element in connection with the second AC input node, wherein the first and second power transistors are controllable to switch the f