Abstract: A magnetic apparatus includes a first magnetic member, a second magnetic member, a first winding, and a second winding, where the first magnetic member includes a first magnetic cylinder, a second magnetic cylinder, a third magnetic cylinder, and at least one fourth magnetic cylinder, and where the first winding is wound around the first magnetic cylinder and the second magnetic cylinder, the second winding is wound around the first magnetic cylinder and the third magnetic cylinder, and a direction in which the first winding is wound around the second magnetic cylinder is opposite to a direction in which the second winding is wound around the third magnetic cylinder.

Abstract: A charger including a charging interface and a converter coupled to the charging interface. The converter includes a first plurality of switching transistors coupled to the charging interface and a transformer including a primary winding, a secondary winding, and an auxiliary winding. The primary winding is coupled to the first plurality of switching transistors. A second plurality of switching transistors is coupled between the secondary winding and a battery interface. An auxiliary system interface is coupled to the auxiliary winding. A controller is configured to control the first plurality of switching transistors and the second plurality of switching transistors to generate a first signal at the battery interface and a second signal at the auxiliary system interface.

Abstract: A multiwinding transformer includes a primary-side winding and a plurality of secondary-side windings. A primary-side bridge circuit to carry out DC/AC power conversion is connected between a primary-side DC terminal connected to a DC power supply and the primary-side winding. A plurality of secondary-side bridge circuits to carry out DC/AC power conversion are connected between the plurality of secondary-side windings and a plurality of secondary-side DC terminals, respectively. The plurality of secondary-side windings include a first secondary-side winding strongest in magnetic coupling to the primary-side winding and a second secondary-side winding weaker in magnetic coupling to the primary-side winding than the first secondary-side winding.

Abstract: A power module includes a printed circuit board (PCB), a magnetic element, primary and secondary winding circuits and a regulator. The magnetic element is disposed on the PCB and has first to fourth sides. The second side is opposite to the first side, the fourth side is opposite to the third side. The primary winding circuit is disposed on the PCB and positioned in a vicinity of the first or second side. The secondary winding circuit is disposed on the first PCB and positioned in a vicinity of the third or fourth side. The regulator includes a switch disposed on the PCB, and coupled to the primary winding circuit. The at least one switch, the primary winding circuit, and the magnetic element are arranged in a first direction in order. A power device is also disclosed herein.

Abstract: A method for controlling the input voltage frequency of a DC-DC converter includes defining a setpoint voltage value, computing a control frequency value of the DC-DC converter as a function of the battery voltage, a power setpoint, and the setpoint input voltage, and applying the control frequency to the converter.

Abstract: A perforated coil surface vaporizing element which may have a negative and positive lead, the leads may be configured for electrical communication with an anode portion and a cathode portion, respectively, of a galvanic cell. The perforated coil surface vaporizing element may be shaped as a helix tubule coil sheet. The coil sheet which may connect to and span between the positive and negative lead. The tubule may further be resistive to electron flow and may generate heat upon passage of electrons from the positive lead to the negative lead. The perforations of the helix tubule coil sheet may be in multiplicity. An aperture may traverse through the middle of the helix tubule and may be further configured to receive a wicking material. The wicking material maintaining fluid communication with a liquid medium for vaporization.

Abstract: A power converter includes a primary H-bridge with switches and an LCL-Transformer section with a first inductor with a first end connected to a first terminal of the primary H-bridge, a capacitor connected between a second end of the first inductor and a second terminal of the primary H-bridge, and a second inductor with a first end connected to the second end of the first inductor. The converter includes a transformer with a primary connected between a second end of the second inductor and the second terminal of the primary H-bridge, a secondary H-bridge with switches with an input connected to a secondary side of the transformer, and an output capacitor connected across output terminals of the secondary H-bridge. The primary H-bridge is fed by a DC constant current source and the output terminals of the secondary H-bridge have a regulated DC output voltage are connected to a load.

Abstract: A DC-DC switching converter includes power switches selectively coupling an output terminal with a first voltage or with a second voltage. A driver stage is coupled with the power switches for driving the power switches. A driver control stage is coupled with the driver stage for controlling the operation of the driver stage. An output current sensing circuit is coupled with the output terminal and with the driver control stage, and is configured to sense a sign of an output current delivered by the DC-DC switching converter at the output terminal and to generate control signals for the driver control stage. The driver control stage controls the operation of the driver stage according to states of the control signals received from the output current sensing circuit, for selectively delaying the activation of the power switches depending on the sensed sign of the output current.

Abstract: An AC-AC converter can include a stack of four switches. An input of the converter can be coupled across the stack of four switches, and an output of the converter can be taken from first terminal coupled to a connection point of first and second switches of the stack and a second terminal coupled to a connection point of third and fourth switches of the stack. The converter can further include a controller that operates the switches such that during a positive half cycle of an AC input voltage, the first and second switches are operated with an alternating 50% duty cycle and the third and fourth switches are constantly on, and during the negative half cycle of the AC input voltage, the third and fourth switches are operated with an alternating 50% duty cycle and the first and second switches are constantly on.

Abstract: A power supply circuit has a push-pull portion having a transformer; first and second terminals of the primary winding, each connected to ground via first and second switches; an inductor connected between an input voltage and the primary winding centre tap via a third switch; an energy storage portion connected between the primary winding and ground, and to the inductor via a fourth switch; a controller arranged to monitor the input voltage and to apply partially overlapping first and second PWM signals to the first and second switches; when input voltage is between first and second thresholds, the controller closes the third switch and opens the fourth switch; above the second threshold, the controller applies a third PWM signal to the third switch and opens the fourth switch; and below the first threshold, the controller closes the third switch and applies a fourth PWM signal to the fourth switch.

Abstract: A transformer for a DC-DC converter, such as a resonant converter, is provided. The converter includes a transformer unit that includes at least one winding with a first winding connection and a second winding connection, and a capacitor assembly consisting of at least one capacitor with a first capacitor assembly connection and a second capacitor assembly connection. The capacitor assembly is arranged so as to lie against the transformer unit in order to form an assembly. The capacitor assembly connections are connected to the winding connections via one or more first connection parts in a specified manner with respect to the electric connections. The capacitor assembly connections and/or the winding connections are electrically connected to multiple second connection parts in a specified manner with respect to the electric connections for connecting to a first power module and a second power module.

Abstract: Embodiments of the present application provide a transformer and a bidirectional isolated resonant converter, where the transformer includes a first side winding, a second side winding, and a magnetic core. The magnetic core includes a winding column, at least one side column and two connecting portions. The first side winding includes: a first side first winding and a first side second winding that are electrically connected, and the second side winding is located between the first side first winding and the first side second winding. An air gap is provided on the winding column, and the air gap is provided between the second side winding and a first end surface of the winding column, and a first side equivalent leakage inductance and a second side equivalent leakage inductance are obtained through the air gap.

Abstract: A resonant converter includes primary and secondary circuits, a transformer, a resonant network and a control circuit. The control circuit is coupled to the primary circuit and the secondary circuit, and configured to control primary switches of the primary circuit operating with a switching frequency. At least one of primary switches is configured to be turned on from a first switching moment until a second switching moment. The control circuit is configured to control secondary switches of the secondary circuit, such that at least one of secondary switches is turned on during a first time interval to increase a current of the resonant network in a first flowing direction and an output current in a second flowing direction or equal to zero.

Abstract: Systems and methods for controlling a dual active bridge converter are disclosed herein. An output voltage of a dual active bridge converter is sensed. Based at least in part on the output voltage, a target intra-bridge phase shift amount between two bridges of the dual active bridge converter is computed. A plurality of switch control signals, which are provided to respective switches of the dual active bridge converter, are caused to switch according to a time-based switching sequence based on the target intra-bridge phase shift amount to compensate for variations in the output voltage.

Abstract: In at least one embodiment, a vehicle battery charger is provided. The charger includes at least one transformer, a first active bridge, a second active bridge, and at least one controller. The first active bridge includes a first plurality of switching devices being positioned with the primary. The second active bridge includes a second plurality of switching devices being positioned with the secondary to generate. The controller is configured to activate the first plurality of switching devices based on a primary control signal and to activate the second plurality of switching devices based on a secondary control signal. The controller is configured to generate the secondary control signal in accordance to a first control variable. The controller is further configured to generate a second control variable that corresponds to a phase shift between the primary control signal and the secondary control signal.

Abstract: Battery management system with integrated contactor economizer. A system for reducing power consumption included herein comprises a switching mechanism comprising a switch, and a microcontroller coupled to the switching mechanism, wherein the switching mechanism is coupled to a coupling mechanism and configured to energize the coupling mechanism, and wherein the processor is configured to provides a pulse width modulated on/off signal with duty cycle ranging between 50% to 100% and frequencies between 1 KHz to 20 KHz.

Abstract: An LLC resonant converting apparatus determines to operate as a half-bridge LLC resonant converter or a full-bridge LLC resonant converter based on the magnitude of the input voltage. The present disclosure can solve the problem that the input voltage range of the LLC resonant converter is not wide enough.

Abstract: A sensor controller, which controls a first optical sensor and a second optical sensor respectively having beam irradiation ranges, shifted from each other, for scanning a substantially front direction and a substantially side direction of a vehicle. The sensor controller: determines when an abnormality occurs in either the first optical sensor or the second optical sensor; identifies an abnormal sensor in which abnormality has occurred and a normal sensor that maintains normality; and controls a beam pattern in a beam irradiation range of the normal sensor to have a degeneration pattern with a high density in a region overlapping a beam irradiation range of the abnormal sensor.

Abstract: A resonant converter having a pre-conduction mechanism for realizing a wide output voltage range is provided. The resonant converter includes a first circuit and a second circuit. The first circuit includes a plurality of primary-side switches. The plurality of primary-side switches includes a first high-side switch, a second high-side switch, a first low-side switch and a second low-side switch. The second circuit includes a plurality of secondary-side switches. The plurality of secondary-side switches includes a third high-side switch, a fourth high-side switch, a third low-side switch and a fourth low-side switch. When the second low-side switch and the first low-side switch are turned on and a current time reaches a preset on time, the fourth high-side switch and the third low-side switch are turned on.

Abstract: A power supply includes a power factor correction (PFC) circuit, a PFC bypass circuit, and a decision circuit. The PFC circuit is configured to receive an input current from a power source and, when enabled, reduce current harmonics in the input current by shaping an input sinusoidal current waveform to match a phase and shape of a sinusoidal input voltage waveform. The PFC bypass circuit is configured to bypass the PFC circuit when the PFC circuit is disabled. The decision circuit includes a detection circuit configured to detect an output load of the power supply and is configured to output a PFC enable command based at least in part on the detected output load being greater than or equal to a threshold value and a determination that an input voltage of the power source is greater than or equal to a threshold value.

Abstract: A semiconductor switch driving apparatus is configured to drive a semiconductor switch, the semiconductor switch not having a body diode and having a threshold voltage for performing switching between off and on lower than a threshold voltage of a silicon device. The semiconductor switch driving apparatus includes: a first drive voltage switching circuit configured to switch a drive voltage of the semiconductor switch to a first adjustment voltage between an off-voltage and an on-voltage, at a predetermined time immediately before a timing at which the semiconductor switch is driven from off to on; and a second drive voltage switching circuit configured to switch, after the drive voltage of the semiconductor switch has been switched by the first drive voltage switching circuit, the drive voltage of the semiconductor switch to the on-voltage at the timing at which the semiconductor switch is driven from off to on.

Abstract: It may be desirable to limit the switching frequency of a pulse frequency modulated (PFM) resonant converter, however certain load conditions and/or startup condition require high switching frequencies to regulate an output voltage. The disclosed resonant converter can limit a maximum switching frequency while regulating an output voltage by shifting from PFM to phase-difference modulation based on a load condition. The appropriate modulation can be applied based on a comparison between a charge-control signal and a load-control signal.

Abstract: A solar photovoltaic output optimizer circuit utilizes generated energy without waste. The optimizer circuit includes a solar photovoltaic power generation input device for receiving the generated output of a solar photovoltaic panel, a switching device, and a voltage doubler rectification device, and further includes: a first power collection circuit that connects a connection point between a source electrode of a second switching transistor of the switching device and one end of a primary winding of a transformer of the voltage doubler rectification device to a drain electrode of a sixth switching transistor; and a second power collection circuit including a seventh switching transistor whose drain electrode is connected to a drain electrode of a fifth switching transistor of the switching device and whose source electrode is connected to a source electrode of the sixth switching transistor of the first power collection circuit and an anode electrode of a third diode.

Abstract: A DC-DC converter includes: a transformer; first and second switching circuits, each coupled to one of two sides of the transformer, respectively, and each including at least two switches; a first current detection module, coupled to one side of the transformer and detecting a current at the side; a first conversion module, coupled to an output of the first current detection module, and converting a signal of the current received from the output to a voltage signal; a first comparison module comparing the voltage signal received from the output with a reference voltage signal, and generating a first modulation signal based on the comparison result; and a first controller generating a first control signal which is used for at least one switch in the second switching circuit and based on the first modulation signal and a drive signal of at least one switch in the first switching circuit.

Abstract: Systems and methods are provided for a soft switching topology for a direct current (DC)-DC converter. The systems and methods determine an operational status of an electric motor, and activate at least one of an upper or lower first or second semiconductor switches based on an operation of the electric motor. The first and second switching circuits are conductively coupled to a power inverter circuit. The systems and methods include deliver an adjusted voltage to one of the power inverter circuit or a power circuit based on the operational status of the electric motor.

Abstract: A brushless DC motor system, includes a single coil brushless DC motor and a driver for driving the single coil brushless DC motor. The brushless DC motor system has a maximum time constant ?max. The driver comprises a control unit which is adapted for driving the brushless DC motor at a constant speed and at a variable speed by applying a PWM driving signal to the coil of the brushless DC motor with a PWM frequency larger than a ratio defined by a constant/?max wherein the ratio is such that a current through the coil is always bigger than a pre-defined undercurrent limit.

Abstract: An integrated magnetic core is provided. The integrated magnetic core includes a first plate and a second plate. The first plate includes a plurality of legs extending outwardly from a first surface of the first plate. The plurality of legs includes first and second oppositely disposed legs and third and fourth oppositely disposed legs. The second plate is coupled to at least the third and fourth legs of the first plate.

Abstract: A direct current-direct current (DC-DC) converter includes a plurality of switches configured to be coupled to a voltage source. The DC-DC converter also includes a transformer having a primary winding coupled to the plurality of switches and a secondary winding. The DC-DC converter further includes a first capacitor; and a second capacitor, wherein the first capacitor is coupled in series with the primary winding, the second capacitor is coupled in parallel with the secondary winding. The first capacitor, the second capacitor, and a leakage inductance of the transformer form a dual-capacitor resonant circuit.

Abstract: A converter includes a switching stage including first and second primary transistors, a resonant stage connected to the switching stage, a transformer including a primary winding connected to the resonant stage, a rectifying stage connected to a secondary winding of the transformer and including first and second synchronous rectifiers, and a controller. The controller is configured and/or programmed to operate in a steady-state mode in which an output voltage of the converter is regulated by varying a switching frequency of the first and second primary transistors and of the first and second synchronous rectifiers and a synchronous-rectification control mode in which the output voltage is regulated when an output-voltage overshoot is detected by switching the first and second primary transistors and the first and second synchronous rectifiers at a fixed switching frequency and by varying a duty cycle of the first and second synchronous rectifiers.

Abstract: Systems and method for optimizing the efficiency of operation of electronic circuits, configured structured according to a true soft-switching phase-shifted full-bridge topology (where all the primary switching elements turn on at zero voltage and the secondary switching elements turn off at zero current with no ringing and no spikes across the secondary switching elements) with the use of unique current-injection approaches. An additional advantage of the embodiments of this invention is that the true soft switching feature applies regardless of the leakage inductance in the transformer.

Abstract: A converter using a planar transformer includes an input device that receives a first voltage, a transformer including a first planar transformer and a second planar transformer that reduce the first voltage, and an output device that outputs the first voltage as a second voltage, wherein the first voltage is greater than the second voltage, and the input device provides a current to a primary winding coil of each of the first planar transformer and the second planar transformer through a first current path and a second current path in which current directions are different with each other, and includes a plurality of inductors connected in parallel with the primary winding coil of each of the first planar transformer and the second planar transformer.

Abstract: A power converter includes a plurality of switches, a transformer electrically connected between some and other of the switches, and a plurality of series connected capacitors electrically connected between the switches and an output of the power converter. A controller operates the switches such that a voltage at an input of the power converter and across each of the capacitors is same and a voltage at the output is double the voltage at the input.

Abstract: An electrical power distribution system includes a first high side sub-module including a high side converter and a high side energy storage device. The first high side sub-module is electrically coupled to a high side load that requires a high voltage or medium voltage DC, the high voltage DC being higher than the medium voltage DC. The system also includes a first low side sub-module including a low side converter and a low side energy storage device. The first high side sub-module and the first low side sub-module are configured to be inductively coupled. The first high side sub-module and the first low side sub-module form a first module.

Abstract: Methods and systems for connecting a photovoltaic module and an inverter having an input capacitor are presented. The photovoltaic system includes a maximum power point tracking (MPPT) controller coupled between the inverter and the photovoltaic module. The MPPT controller includes a direct current (DC) converter configured to reduce, in a forward buck mode, a voltage of the photovoltaic module, to supply power from the photovoltaic module to the input capacitor of the inverter. The photovoltaic system also includes a microcontroller unit (MCU) configured to control the DC converter to allow the photovoltaic module to operate at a maximum power point, and to increase, in a reverse boost mode, a voltage of the input capacitor of the inverter, to dissipate power from the input capacitor in the photovoltaic module, and the MPPT controller is configured to, based upon one or more triggers.

Abstract: A synchronous average harmonic current controller for a line connected bidirectional resonant power converter results in a harmonic voltage gain closely related to the commanded bridge duty cycles. A primary bridge has its duty cycle set to achieve controlled line power transfer and voltage regulation of a primary bus energy storage capacitor. A secondary bridge circuit has its duty cycle set to achieve voltage regulation of secondary bus energy storage capacitor. A first embodiment uses the independent energy storage elements to achieve power factor correction and low noise regulation using a single stage. A second embodiment uses feedforward duty cycle control to achieve isolated voltage regulation using the well-defined voltage gain resulting from the synchronous average harmonic current controller.

Abstract: A drive circuit includes a first driver to control on/off of an upper arm, a second driver to control on/off of a lower arm, a first switching device including a first terminal connected with a power supply for the first driver, a second terminal connected with a power supply for the second driver and a control terminal, a booster circuit to turn on the first switching device by boosting a control signal which is at a high level when the lower arm is in an on state, a second switching device to cause continuity between the control terminal and the booster circuit when the control signal is at the high level, and first switch unit to short-circuit the control terminal and the terminal for grounding when the control signal is at the low level.

Abstract: A controller of a switching converter includes an error amplifying circuit, a first comparison circuit, a valley detection circuit, a valley selection circuit and a frequency control circuit. The error amplifying circuit generates a compensation signal based on the difference between a reference signal and a feedback signal. The first comparison circuit compares the compensation signal with a modulation signal and generates a pulse frequency modulation signal. The valley detection circuit detects valleys of a resonant voltage of the switching converter and generates a valley pulse signal. The valley selection circuit generates a valley enable signal corresponding to a target valley number based on the pulse frequency modulation signal and the valley pulse signal. The frequency control circuit generates a frequency control signal to control the switching frequency of the first switch based on the valley enable signal and the valley pulse signal.

Abstract: An LLC resonant converter including a transformer, a switching full-bridge circuit, a resonant circuit, and a bridge rectifier. The switching full-bridge circuit has a first pair of switches and a second pair of switches, with the first pair of switches being connected between a DC input voltage and a second end of a secondary winding of the transformer, the second pair of switches being connected between a DC input voltage and a first end of the secondary winding of the transformer.

Abstract: A controller of a power converter is coupled to a switch assembly and configured to perform a hold-up time procedure that causes the controller to control first and second switching elements into opposite conducting states during a first period of time of a pulse cycle and into alternate opposite conducting states during a second period of time of the pulse cycle. The hold-up time procedure also causes the controller to control a first pair of synchronous rectifier switching devices into a conducting state during a third period of time overlapping less than all of the first period of time and into the conducting state during a fourth period of time overlapping less than all of the second period of time. A second pair of synchronous rectifier switching devices is controlled into a non-conducting state during the first and second periods of time.

Abstract: An LLC resonant converter includes a transformer and a primary-side circuit coupled to the transformer. The primary-side circuit includes a first bridge arm, a second bridge arm, and a control unit. The first bridge arm includes a first switch and a second switch, and the second bridge arm includes a third switch and a fourth switch. The control unit provides a first control signal to control the first switch and provides a fourth control signal to control the fourth switch. The control unit adjusts a switching frequency of the first control signal and the fourth control signal according to an output voltage. When the switching frequency increases to a frequency threshold value, the switching frequency is controlled to be fixed at the frequency threshold, and the first control signal and the fourth control signal are controlled to have a variable phase difference.

Abstract: The present disclosure provides a power conversion device including an input end having positive and negative input terminals, two bridge arms, two transformers and an output capacitor. Each bridge arm is connected to the input end in parallel, and includes three switches coupled in series. Two terminals of one switch are electrically connected to the positive input terminal and a primary node respectively. Two terminals of another switch are electrically connected to the negative input terminal and a secondary node respectively. Each transformer includes primary and secondary windings coupled to each other. Two primary windings are serially coupled between two primary nodes. Two secondary windings are serially coupled between two secondary nodes. Two terminals of the output capacitor are electrically connected to output positive and negative terminals respectively.

Abstract: An LLC resonance converter includes a switching circuit, a resonance tank, a transformer, a synchronous rectification unit, and a control unit. The switching circuit includes a first switch controlled by a first control signal and a second switch controlled by a second control signal. The synchronous rectification unit includes a first synchronous rectification switch controlled by a first rectification control signal and a second synchronous rectification switch controlled by a second rectification control signal. The first control signal, the first rectification control signal, the second control signal, and the second rectification control signal include an operation frequency and a phase shift amount. When the operating frequency is lower to a specific value or the phase shift amount is higher to a specific value, the control unit fixes one of them to extend a hold-up time of the LLC resonance converter.

Abstract: A dual active bridge includes a first converter arranged on a primary side of the dual active bridge, a second converter arranged on a secondary side of the dual active bridge, a high frequency transformer that has two windings and that operatively connects the first converter to the second converter, and a plurality of inductors, which are arranged along the legs on one of the two windings of the high frequency transformer, and which are split between the legs of that winding. In one embodiment, the plurality of inductors are split between the legs of the winding disposed on the secondary side of the dual active bridge. The plurality of inductors may consist of two inductors, of which a first one is arranged of the first leg of the winding and a second one is arranged on the second leg of the winding.

Abstract: A method for identifying a malfunctioning current sensor in an electrical apparatus, in which an electrical power supply of the electrical apparatus is at least partly supplied by a switched-mode electrical power supply circuit connected to at least one current sensor which samples an electrical current in a phase conductor of an electrical installation, the power supply circuit delivering a regulated electrical voltage, the method including: determining a switching duty cycle of a power switch of the switched-mode electrical power supply; analysing the determined switching duty cycle; and identifying a failure condition if the behaviour of the switching duty cycle is representative of a malfunctioning of at least one of the current sensors.

Abstract: A power converter having a parallel resonant circuit, includes an inverter, a resonant circuit, a transformer comprising a primary circuit and a secondary circuit, control means for the inverter, the inverter being connected to the resonant circuit, which is intended to be connected to an output load via the transformer, the power converter wherein the inverter comprises a first half-bridge and a second half-bridge in parallel with the first half-bridge, a first inductor between the first half-bridge and the resonant circuit, a second inductor between the second half-bridge and the resonant circuit, and in that the first and second inductors have the same inductance and are coupled in the opposite direction to one another.

Abstract: Envelope tracking systems for power amplifiers are provided herein. In certain embodiments, an envelope tracker is provided for a power amplifier that amplifies an RF signal. The envelope tracker includes a multi-level switching circuit having an output that provides an output current that changes in relation to an envelope signal indicating an envelope of the RF signal when the envelope tracker is operating in an envelope tracking mode. The multi-level switching circuit includes a multi-level supply (MLS) modulator that receives multiple regulated voltages of different voltage levels, and an MLS control circuit that controls the selection of the MLS modulator over time based on the envelope signal. When transitioning the MLS modulator from selection of one regulated voltage level to another regulated voltage level, the MLS control circuit provides a soft transition to gradually switch the regulated voltage levels.

Abstract: An image display apparatus is disclosed. The image display apparatus includes a display and a power supply configured to supply driving voltage to the display, wherein the power supply includes a converter to convert input AC voltage into DC voltage and a controller to control the converter, the converter includes a first leg including a first switching device and a second switching device connected to each other in series and a second leg including a first diode and a second diode connected to each other in series, the first diode and the second diode connected to the first leg in parallel, and the controller controls on time of the first switching device to gradually increase from a first level to a second level for a first period for which the input AC voltage rises after a zero crossing point.

Abstract: A resonant converter includes a transformer, a resonant network, control circuit, primary and secondary circuits. One of the primary switches is turned on from a first switching moment until a second switching moment. The resonant network is coupled between the primary circuit and the primary winding. A current of the resonant network changes a direction at a first moment between the first and second switching moments. The secondary circuit is coupled to the secondary winding. One of the secondary switches is turned on during first and second preset time interval to increase the current in a direction by the secondary winding being clamped by a preset voltage, in which the output current is increased in an opposite direction or equal to zero.

Abstract: Various embodiments relate to a converter controller configured to control a resonant converter, including: an integrator configured to receive a current measurement signal from a current measurement circuit in the resonant converter and to produce a capacitor voltage signal indicative of the voltage at the resonant capacitor; a control logic configured to produce a high side driver signal, a low side driver signal, a symmetry error signal based upon the capacitor voltage signal and the current measurement signal; and a symmetry controller configured to produce a symmetry correction signal based upon the symmetry error signal, wherein the symmetry error signal is input into the integrator to control the duty cycle of the high side driver signal and the low side driver signal, wherein the high side driver signal and the low side driver signal control the operation of the resonant converter.

Abstract: Provided is a resonant power conversion apparatus including a gate control circuit that controls a first switch to enter an On state and a second switch to enter an Off state at a first stage and controls the first switch to enter the Off state and the second switch to enter the On state at a second stage, a first current transformer that applies current to the first switch at the first stage and applies current to the second switch at the second stage, a load connected to the first current transformer in series, a second current transformer connected to the second switch, and a microcontroller unit (MCU) that determines whether to be zero voltage switching or non-zero voltage switching based on a current flowing in the first current transformer and the second current transformer in a process of transitioning from the first stage to the second stage.