This disclosure describes systems, methods, and apparatus for controlling a voltage provided to a plurality of configurable output modules using a resonant converter, the resonant converter comprising: an inverter circuit; a resonant capacitor bridge coupled across the inverter circuit; N groups of output modules, each of the N groups comprising terminals configured for coupling to up to M output modules, the output modules each comprising: a transformer having a primary and a secondary; and a rectified output coupled to the secondary and configured for coupling to a load; and a resonant inductor network configured to be coupled between the resonant capacitor bridge and the primaries of the transformers, the resonant inductor network comprising: at least one parallel inductor; and N parallel branches arranged in parallel and each branch comprising a series inductor, each of the series inductors configured for transformer-coupling to up to M output modules.

A soft switching resonant converter is disclosed. The converter includes a power switch operable to connect and disconnect a DC link rail node and an output node. A resonant capacitor is coupled with the power switch. An auxiliary leg is coupled with a DC link midpoint node and the output node. An active damper is coupled in series with the resonant capacitor and the output node and is controllable to provide a first resistance of the active damper in a first state and a second resistance of the active damper in a second state, the first resistance having a lower magnitude than the second resistance. A driver controls the damper switch to provide a first resistance during the soft switching operation of the power switch and a second resistance after the soft switching operation of the power switch.

A power receiver includes: a secondary-side resonant coil including a resonant coil part to receive electric power from a primary-side resonant coil through magnetic field resonance; a capacitor inserted in series in the resonant coil part; a series circuit of a first switch and a second switch; a first rectifier having a first rectification direction; a second rectifier having a second rectification direction; a detector to detect a voltage waveform or a current waveform of the power; and a controller to adjust, in a state of adjusting a phase difference between the waveform and a driving signal that includes a first signal for switching on/off the first switch and a second signal for switching on/off the second switch to be a predetermined phase difference, a length of a period, during which the switches are both on, to adjust an amount of the power received by the secondary-side resonant coil.

A power converter circuit includes a chopper circuit configured to receive an input voltage and generate a chopper voltage with an alternating voltage level based on the input voltage, an autotransformer including at least one tap, the autotransformer being coupled to the chopper circuit and configured to generate a tap voltage at the at least one tap, and a selector circuit configured to receive a plurality of voltage levels. At least one of these the voltage levels is based on the at least one tap voltage. The selector circuit is further configured to generate a selector output voltage based on the plurality of voltage levels such that the selector circuit selects two of the plurality of voltage levels and switches at a switching frequency between the two voltage levels.

A quasi-resonant auto-tuning controller includes a zero-voltage crossing detection circuit and a valley tuning finite-state machine having a look-up table. The zero-voltage crossing detection circuit receives a reference voltage and receives an auxiliary signal from an auxiliary winding. The zero-voltage crossing detection circuit produces a comparison signal having pulses when the auxiliary signal is less than the reference voltage. The valley tuning finite-state machine produces a divided pulse width based on the comparison signal, stores the divided pulse width of each pulse in the look-up table, determines, from the comparison signal, that the auxiliary signal is less than the reference voltage, waits a time period corresponding to the divided pulse width stored in the look-up table if the auxiliary signal is less than the reference voltage, and produces a valley point signal after waiting the time period.

Disclosed is a power converter including a generator configured to generate a sequence of output voltage waveforms, a resonant tank connected to the generator comprising at least one capacitor and at least one inductor, a transformer including a primary side connected in series with said series inductor and, the primary side being configurable to use at least one primary winding tap and a secondary side for connecting to a rectifying circuit for providing a rectified DC voltage to an output load circuit, a first switch and a second switch on the primary side connected to the primary winding, wherein the at least one primary winding is selected by the first switch or the second switch to select a different reflected output voltage by closing the first switch or the second switch.

Unique systems, methods, techniques and apparatuses for a ZVT ZCT resonant converter with a variable resonant tank are disclosed. One exemplary embodiment is a system comprising a bidirectional resonant converter comprising an input/output terminal, a switching device coupled with the input/output terminal, a resonant circuit coupled with the switching device and including a variable inductor, an output/input terminal coupled with the resonant circuit, and a DC biasing circuit operatively coupled with the variable inductor. The variable inductor comprises a toroidal core, a first winding wound around the toroidal core and coupled with the switching device and the output/input terminal, a second core structured to overlap a portion of the toroidal core, and a second winding wound around the second core and coupled with the DC biasing circuit. The DC biasing circuit is controllable to vary the inductance of the variable inductor by saturating a portion of the toroidal core.

A power conversion system in which a converter and an inverter are coupled to each other via a DC coupling unit that has an inductance component is provided. A switching frequency of each of the converter and the inverter is set to be the same and the switching frequency is set to be higher than a resonance frequency of a resonance circuit that includes a first capacitor, a second capacitor, and the DC coupling unit such as a cable. A switching operation of at least one of the converter or the inverter is controlled such that phases of predetermined components of voltage ripples, at the first capacitor and the second capacitor, that are respectively generated by switching operations of the converter and the inverter are substantially matched.

A semiconductor device includes: a first circuit, including semiconductor switching elements connected in parallel, each semiconductor switching element having a first electrode, a second electrode, and a third electrode and being configured to be controlled, according to a voltage between the first electrode and the third electrode, to attain conduction or non-conduction between the second electrode and the third electrode; and a control unit connected to the first electrode of each semiconductor switching element and configured to control the voltage between the first electrode and the third electrode. The semiconductor device is configured to satisfy a first condition that an impedance Zg on a first path between the first electrodes of the respective semiconductor switching elements is higher, by at least a set value, than an impedance Zs on a third path making connection between the third electrodes of the respective semiconductor switching elements.

Disclosed is an AC-AC power converter with multiple AC voltage output branches. The AC-AC power converter is bridgeless and contains only one power stage. The AC-AC power converter consists of only one inductor for power conversion and provides a current source for successively feeding multiple output branches one at a time. Each output branch can be selected by the corresponding switch and its resonant circuit turns the input current source into an AC power source.