Abstract: An AC-DC photovoltaic device is provided, including: a photovoltaic module, a direct current side capacitor, a DC-PWM power switching circuit and a controller. The direct current side capacitor is connected in parallel with an output terminal of the photovoltaic module. An input terminal of the DC-PWM power switching circuit is connected with the output terminal of the photovoltaic module. The DC-PWM power switching circuit includes a controllable switch transistor. The controller is configured to output a switch control signal to control a switching state of the controllable switch transistor in the DC-PWM power switching circuit, to control the DC-PWM power switching circuit to output a direct current PWM wave in a case that the switch control signal is a direct current modulation signal, and output an alternating current PWM wave in a case that the switch control signal is an alternating current modulation signal.

Abstract: Provided are a power converting system and a power converting apparatus, which include an input unit that receives a direct current (DC) voltage from an external power source, a conversion unit including a plurality of switching circuits that convert the input DC voltage into a multi-phase AC voltage, a resonant unit including a single resonant inductor connected to each of the plurality of switching circuits, and an output unit that rectifies each phase of the multi-phase AC voltage which has been converted in the plurality of switching circuits and outputs a single DC voltage.

Abstract: The disclosure reduces the size and cost of a power conditioner. A power conditioner including a DC/DC converter connected to a power supply device and an inverter connected to the DC/DC converter includes: a plus side wiring connecting the DC/DC converter and the inverter; a minus side wiring connecting the DC/DC converter and the inverter; a capacitor having one end connected to the plus side wiring and an other end connected to the minus side wiring; and a fuse provided on the minus side wiring, wherein the DC/DC converter has at least one switching element; the other end of the capacitor is connected to a first connection point provided on the minus side wiring on the DC/DC converter side with respect to the fuse; and the switching element is connected to a second connection point provided on the minus side wiring on the inverter side with respect to the fuse.

Abstract: A switch drive circuit drives a full-bridge output stage connected to a transformer to alternately switch between a first cycle in which a current in a first direction is supplied to the transformer and a second cycle in which a current in a second direction is supplied to the transformer. The switch drive circuit includes a mode in which a dead time of the output stage is set in accordance with a magnitude of a current flown in one of the first and second cycles, the dead time becoming an operation changing factor in the other cycle. Or, the switch drive circuit includes a mode in which the dead time of the output stage is set in accordance with a magnitude of an average current obtained by averaging currents flown in the first and second cycles. Or, the switch drive circuit switches between these modes in accordance with a signal.

Abstract: A power converter including a bridge circuit is provided. The power converter is designed to convert a direct current of a current source into an alternating current and/or an alternating current into a direct current. The bridge circuit includes a first parallel circuit assembly, which is coupled to a higher potential of the current source and which has a plurality of switching elements connected in parallel, a second parallel circuit assembly, which is coupled to a lower potential of the current source and which has a plurality of switching elements connected in parallel, and a plurality of taps, which are each coupled to the first and second parallel circuit assemblies. Each switching element of the first and the second parallel circuit assemblies has two conducting connections and a control connection, which controls the flow of current from one conducting connection to the other conducting connection.

Abstract: Welding circuits including superposition elements that charge and discharge to assist with re-establishing a welding arc between an electrode and a workpiece after the arc is extinguished when a welding output current polarity changes are described.

Abstract: An embodiment of the present invention is directed to an integrated electromagnetic compatibility (EMC) filter and power line communication (PLC) interface. The EMC filter and PLC interface comprises a first filter winding and a second filter winding configured as a common mode choke; and a two-part winding on the common mode choke, wherein the two-part winding comprises (i) a first winding coupled proximate the first filter winding and (ii) a second winding coupled proximate the second filter winding, wherein the first winding and the second winding have an equal number of turns, and wherein phasing of the first winding is reversed with respect to the second winding.

Abstract: In the field of high voltage direct current power transmission and distribution there is provided a converter which includes first and second DC terminals for connection to a DC electrical network and between which extends converter limbs. Each converter limb includes first and second limb portions that are separated by an AC terminal for connection to a respective phase of a multi-phase AC electrical network. Each limb portion includes a current sensor to measure current flowing in the corresponding limb portion. The converter also includes further current sensors, located elsewhere in the converter, and a current sensor management unit. The current sensor management unit is programmed to: receive a measured current value from each current sensor; identify at least one faulty current sensor from the received measured current values; and replace the measured current value of the or each identified faulty current sensor with a calculated current value.

Abstract: A multilevel converter includes single phase configurations. A single phase configuration has a first half-bridge (HB) module, a second HB module separated by a first capacitor coupled to a DC link, and a neutral point clamped (NPC) module clamped to the first HB module and the second HB module. Further, the single phase configuration has a first individual switching device and a second individual switching device, the first individual switching device operably connected to the first HB module and the NPC module, and the second individual switching device operably connected to the second HB module and the NPC module. The converter further includes a power output assembly comprising multiple phases and providing multiple-phase alternating (AC) power, wherein the single phase configuration supplies power to one of the multiple phases of the power output assembly.

Abstract: An electric propulsion system includes at least one generator. The electric propulsion system also includes at least one drive engine coupled to the at least one generator. The electric propulsion system further includes at least one electrical device. The electric propulsion system also includes at least one battery integrated isolated power converter (BIIC), where the at least one generator and at least one of the at least one BIIC and the at least one electrical device are coupled, and where the at least one BIIC and the at least one electrical device are coupled.

Abstract: A switch driving circuit is provided, wherein the switch driving circuit has a function of periodically updating a simultaneous OFF time prepared to soft-switch an upper switch and a lower switch of a switching output circuit, and is configured to monitor how an output power or an input power of the switching output circuit is changed depending on previous updating of the simultaneous OFF time to determine new updated contents.

Abstract: A power management apparatus is provided. The apparatus is configured to connect a plurality of DC power elements to a plurality of AC power elements and includes a DC interface module connected to the plurality of DC power elements, a bi-directional AC-DC converter connected to the DC interface module, and an AC interface module connected to the bi-directional AC-DC converter and the AC power elements.

Abstract: This disclosure relates to an equivalent transistor and a three-level inverter, and pertains to the field of power electronics technologies. The equivalent transistor includes a first transistor, a second transistor, and a diode. A source electrode of the first transistor is electrically connected to a source electrode of the second transistor; a gate electrode of the first transistor is electrically connected to a gate electrode of the second transistor; and one end of the diode is electrically connected to a drain electrode of the first transistor, and the other end of the diode is electrically connected to a drain electrode of the second transistor. According to this disclosure, a reverse recovery time can be reduced, and a switching speed of the equivalent transistor can increase.

Abstract: There is provided a semiconductor device capable of decreasing a switching loss. The semiconductor device has first semiconductor elements (Su)-(Sw) and second semiconductor elements (Sx)-(Sz) connected in series, in which the first semiconductor element includes a low switching loss semiconductor element having a switching loss which is smaller than a switching loss of the second semiconductor element and the second semiconductor element includes a low conduction loss semiconductor element having a conduction loss which is smaller than a conduction loss of the first semiconductor element.

Abstract: The invention relates to a chip (1) for use in an operating device for lighting means, wherein the chip (1) is designed to control a processing block (2) of an operating device for lighting means, wherein the chip (1) can control a plurality of different processing blocks (2) which differ in their function, wherein the chip (1) is designed to select on the basis of at least one signal applied to the chip (1) what type of processing block (2) should be controlled.

Abstract: In a power conversion apparatus, a controller calculates a duty ratio being a ratio of an on-duration of each of bridge-circuit switches configured by first to fourth switches to a switching period, and outputs a gate signal to each of the bridge-circuit switches. The controller adjusts the duty ratio of each of the bridge-circuit switches such that a switch-current difference becomes closer to a value obtained by multiplying an input-current difference by the predetermined target ratio that is a value greater than 0 and less than 1. The switch-current difference is a difference between a first switch current and a second switch current or a difference between a third switch current and a fourth switch current detected by a switch-current sensor at predetermined timings in the switching period. The input-current difference is a difference between input currents detected by an input-current sensor simultaneously with detection timings of switch currents.

Abstract: A bidirectional switch is switched so as to conduct and interrupt a bidirectional current between a pair of input terminals. A power supply is electrically connected between the pair of input terminals and produces control power by electric power from an AC power supply. A controller receives the control power from the power supply to be activated. The controller causes the bidirectional switch to be in an off-state from a start point of a half cycle of AC voltage to a first time point when first time elapses. The controller causes the bidirectional switch to be in an on-state from the first time point to a second time point when second time according to the dimming level elapses. The controller causes the bidirectional switch to be in an off-state from the second time point to an end point of the half cycle.

Abstract: A control method implemented for an electric motor control installation, the control installation including a first converter having controlled switching arms for applying first voltage edges to a first electric motor connected to the first converter by first output phases, a second converter having controlled switching arms for applying second voltage edges to a second electric motor connected to the second converter by second outlet phases, the control method including a step of synchronizing first voltage edges with second voltage edges in order to minimize the common-mode currents generated by the installation.

Abstract: A substrate voltage control circuit comprising: a first connection terminal; a second connection terminal; a substrate voltage control terminal; a first switch having a first source, a first drain, and a first gate, the first source being connected to the substrate voltage control terminal, the first drain being connected to the first connection terminal; a first resistor connected between the first gate and the second connection terminal; a second switch having a second source, a second drain, and a second gate, the second source being connected to the substrate voltage control terminal, the second drain being connected to the second connection terminal; and a second resistor connected between the second gate and the first connection terminal.

Abstract: A filter for a power converter provided in-line with at least one live line of a power network. The filter has an input section with an input inductance provided at an input of the power converter and an output section with an output inductance provided at an output of the power converter. A neutral inductance provided between the power converter and a neutral line of the power network such that the neutral inductance is not in-line with the neutral line of the power network. The neutral inductance is shared by the input section and the output section.

Abstract: A semiconductor device includes self-arc-extinguishing elements and a clamp circuit. Each of the self-arc-extinguishing elements has a control terminal and main electrode terminals. The clamp circuit clamps, at the time of turnoff of one of the self-arc-extinguishing elements, the voltage between the main electrode terminals of the self-arc-extinguishing element at a clamp voltage set equal to or lower than 70% of a static withstand voltage that the self-arc-extinguishing element has. The self-arc-extinguishing elements are connected in series with each other. The clamp circuit may be provided between the control terminal and the main electrode terminal of the self-arc-extinguishing elements. The clamp circuit may include a circuit formed by connecting Zener diodes in series such that an anode of one of the Zener diodes is connected to a cathode of another Zener diode.

Abstract: In operation of a flybuck converter, a first output capacitor is charged and, after this charging, charge is transferred from the first output capacitor to a second output capacitor. The charge transferring includes closing a switch to establish a first current path through which the first output capacitor discharges current that induces, in a second current path, current that charges the second output capacitor. While the switch is closed during the charge transfer, a current limit condition in the switch is detected. In response to detection of the current limit condition, the switch is opened, and is thereafter closed again before attempting to charge the first output capacitor again, thereby to resume transferring charge from the first output capacitor to the second output capacitor.

Abstract: A control device applied to a flyback converter including an auxiliary switch includes: a current detector configured to detect an amplitude of a current of the flyback converter to obtain an amplitude of a negative magnetizing current of the flyback converter; and a comparator controller configured to compare the amplitude of the negative magnetizing current obtained by the current detector with a reference value, and turn off the auxiliary switch according to a comparison result. According to the present disclosure, it is able to achieve zero-voltage switching of a primary-side switch of the flyback converter with variable outputs.

Abstract: An electric system of an aircraft includes a power stabilizing device connected to a primary AC bus and a secondary battery. The secondary battery has a rated voltage which allows the secondary battery to absorb regenerative power from a control surface actuator. Based on a voltage and a frequency in the primary AC bus, charging/discharging of the secondary battery is controlled to stabilize the electric system.

Abstract: The present invention is concerned with a four-level voltage source converter topology including two intermediate converter branches connecting two intermediate voltage levels to a load terminal, and including a interconnect switch coupling the two intermediate branches. The interconnect switch replaces two controlled switches present in corresponding four-level prior art topologies. The four-level converter thus requires, for a full bidirectional implementation, only five active switches. The reduced number of active switches/gate drivers and the four available output voltage levels make this solution interesting for lower cost power electronics with improved reliability, good power quality and minimized filtering requirement.

Abstract: A wireless power transmitter includes a common bridge circuit configured to apply a first alternating current (AC) voltage to a terminal of each of a first resonator and a second resonator of the resonators, a first sub-bridge circuit configured to apply a second alternating current (AC) voltage to another terminal of the first resonator while the first alternating current (AC) voltage is being applied to the terminal of the first resonator, and a second sub-bridge circuit configured to apply a third alternating current (AC) voltage to another terminal of the second resonator while the first alternating current (AC) voltage is being applied to the terminal of the first resonator.

Abstract: A power converter connected between a direct current power supply and a load, the power converter including a switching unit energizing the load based on inputted control signal, a voltage detector detecting a voltage of the direct current power supply, and a protection operation portion detecting a steep elevation of the voltage and performing protection operation to stop a switching operation by the switching unit, wherein the protection operation portion includes an addition circuit adding a predetermined voltage to the voltage detected by the voltage detector and a delay time generator connected to an output of the addition circuit, and wherein the protection operation is performed when a difference between the voltage detected by the voltage detector and an output voltage of the delay time generator reaches a certain value.

Abstract: A high voltage inductive adder is disclosed. In some embodiments, the high voltage inductive adder comprising a first adder circuit and a second adder circuit. The first adder circuit including a first source; a first switch electrically coupled with the first source; a first transformer core; and a first plurality of primary windings wound about the first transformer core and electrically coupled with the first switch. The second adder circuit including a second source; a second switch electrically coupled with the second source; a second transformer core; and a second plurality of primary windings wound about the second transformer core and electrically coupled with the second switch. The high voltage inductive adder comprising one or more secondary windings wound around both the first transformer core and the second transformer core and an output coupled with the plurality of secondary windings.

Abstract: A switching power supply device includes: a plurality of power supply circuits which include a first power supply circuit and a second power supply circuit and respectively correspond to a plurality of phases of a multiphase AC power supply; a switching circuit; an inrush current prevention (ICP) circuit; and a control circuit. The control circuit causes the switching circuit to switch a phase to be connected to the second power supply circuit to a phase corresponding to the first power supply circuit, and causes the ICP circuit to function so that initial charge of electrolyte capacitors included in the respective power supply circuits is performed. After the initial charge is completed, the control circuit causes the switching circuit to switch the phase to be connected to the second power supply circuit to the phase corresponding to the second power supply circuit, and causes the ICP circuit to turn off.

Abstract: A power supply apparatus includes a boosting converter, an inrush current limiting element, a detection circuit, a switch element, and a control circuit. The inrush current limiting element is configured to limit an inrush current to the boosting converter. The detection circuit is configured to detect whether an output voltage of the boosting converter has reached a set voltage. The switch element is configured to short-circuit the inrush current limiting element. The control circuit is configured to operate the switch element according to the detection to short-circuit the inrush current limiting element.

Abstract: Circuits and methods are provided for using a switching voltage converter to convert an input voltage into an output voltage. The voltage converter includes multiple switch stages, and the switch stages are coupled to each other both galvanically and magnetically. Power is transferred among the switch stages magnetically via magnetic coupling elements (e.g., transformer windings) that are coupled to each of the switch stages. The magnetic power transfer allows the voltage converter to support high power transfers, while the galvanic connections between the switch stages allows for relatively simple control of switches within the switch stages. Inductances associated with the magnetic coupling elements, may provide zero-voltage switching (ZVS) of the switches. Due to the simple switch control, magnetic power transfer, and ZVS, the provided voltage converters support relatively high power transfers in an efficient manner.

Abstract: An interleaved multi-phase power supply with a plurality of DC-DC converter ICs. Each DC-DC converter IC has a current sharing pin, and the current sharing pins of the plurality of DC-DC converter ICs are connected together. Each DC-DC converter IC receives a feedback voltage signal to compare with a reference voltage signal to generate an error voltage signal as a reference of an output current of the corresponding DC-DC converter IC. And each DC-DC converter IC has a mismatch voltage regulation module regulating the error voltage signal to be equal to an average of error voltage signals of the plurality of DC-DC converter ICs.

Abstract: Circuits and methods are provided for voltage conversion within a switched-capacitor converter (SCC). The SCC includes multiple switch stages cascaded together. Each switch stage includes two half bridges connected in parallel. Each half bridge has a high and low-side switch connected at a switching node. The switching nodes of each half bridge of each switch stage are coupled to corresponding switching nodes of some other switch stage via capacitors. The switches are controlled such that during a first interval, a phase A capacitor attached to each switch stage is charged while a phase B capacitor is discharged. During a second interval, the phase B capacitor is charged while the phase A capacitor is discharged. By alternating the intervals thusly, one of the capacitors coupled to each switch stage is nearly always discharging such that it can provide current to an output of the SCC or some adjacent switch stage.

Abstract: A power converter for converting an electric power for a motor that has three-phase winding wires includes an inverter and a controller. The controller controls the electric power supplied for the three-phase winding wires. The controller either (i) sets a two-phase modulation period for performing a two-phase modulation control when a third-order harmonic frequency that is calculated as triple the frequency of a fundamental frequency of the phase currents is smaller than an audible lower limit frequency of a human audible frequency range, or (ii) performs a three-phase modulation control, when the third-order harmonic frequency is equal to or greater than the audible lower limit frequency. In such manner, a heat generation from the maximum heat generating portion of the power converter is mitigated, and acoustical noise that is generated in the audible frequency range is reduced.

Abstract: A transformerless DC to AC inverter providing an AC output at a power line voltage and at a power line frequency suitable for driving AC loads or appliances and having DC bias measurement circuitry for continuously assessing the magnitude of any DC bias component on the AC output, such as due to fault conditions or non-linear loads, and operative to eliminate or reduce any unwanted DC bias component from the AC output.

Abstract: A flyback converter implements a Forced Zero Voltage Switching (ZVS) timing control by detecting a positive current excursion of the secondary winding current as the synchronous rectifier turn off trigger. The synchronous rectifier switch is turned on near the end of the switching cycle or the on duration is extended to develop a current ripple on the secondary winding current. The control circuit of the flyback converter detects a positive current excursion on the secondary winding current to turn off the synchronous rectifier and to start the next switching cycle. At this point, the voltage across the primary switch has been discharged and the primary switch can be turned on with zero drain-to-source voltage. In other embodiments, zero voltage switching for the off-transition of the primary switch is realized by coupling a capacitor across the primary switch or by coupling a capacitor across the primary winding, or both.

Abstract: A system for integrating energy storage into a modular power converter includes at least one energy storage unit coupled to a first converter for converting a first direct current (DC) voltage of the at least one energy storage unit into a first high frequency alternating current (AC) voltage. At least three phase legs of the modular power converter generate three phase AC voltages. Each phase leg includes a plurality of switching modules connected in series. The switching modules have a plurality of fully controllable semiconductor switches, an energy storage device, and a second converter coupled to the respective energy storage device for converting a second DC voltage of the energy storage device into a second high frequency AC voltage. In the system, three similarly positioned switching modules of the three phase legs form one power unit.

Abstract: The various implementations described herein include inverter devices and systems. In one aspect, an inverter includes: a case; a capacitor within the case having a first terminal and a second terminal; a first bus bar including a first portion within the case and a second portion extending from the case to contact a first transistor; a second bus bar including a first portion situated in the case and a second portion extending from the case to contact a second transistor; and a phase-out bus bar including a first portion situated in the case, a second portion extending from the case to contact the first transistor, and a third portion extending from the case to contact the second transistor.

Abstract: A first drive circuit Da includes a temperature information transmission unit that transmits a binary output signal changing between High and Low and an abnormality information transmission unit that transmits an output signal fixed to Low, and a second drive circuit Db includes the abnormality information transmission unit. A temperature information signal and an abnormality information signal from the first drive circuit Da are subjected to OR operation on the side nearer the first drive circuit Da than to a magnetic coupler Ma so the abnormality information signal takes precedence when the abnormality information signal represents an abnormality, or on the side nearer a control unit than to the insulation elements Da and Db so the output signal from the insulation element Db takes precedence when the abnormality information signal from the second drive circuit Da represents an abnormality, and then the logical sum is output to the control unit.

Abstract: System and method are provided for protecting a power converter. The system includes a first comparator, and an off-time component. The first comparator is configured to receive a sensing signal and a first threshold signal and generate a first comparison signal based on at least information associated with the sensing signal and the first threshold signal, the power converter being associated with a switching frequency and further including a switch configured to affect the primary current. The off-time component is configured to receive the first comparison signal and generate an off-time signal based on at least information associated with the first comparison signal. The off-time component is further configured to, if the first comparison signal indicates the sensing signal to be larger than the first threshold signal in magnitude, generate the off-time signal to keep the switch to be turned off for at least a predetermined period of time.

Abstract: A converter includes a switching circuit, a resonant circuit, a rectifying circuit, and a transformer including a primary winding, and a secondary winding. The switching circuit is configured to convert a DC input voltage to a switching signal. The resonant circuit is electrically coupled to the switching circuit and configured to receive the switching signal to provide a primary current. The primary winding is coupled to the resonant circuit. The rectifying circuit is coupled to the secondary winding and configured to rectify a secondary current outputted by the secondary winding so as to provide an output voltage. The resonant circuit includes a variable inductor to adjust the characteristic curve of the converter.

Abstract: A power conversion apparatus and a power conversion method are provided for heat treatment. The power conversion apparatus includes a rectifier configured to convert AC power to DC power, a smoothing filter configured to control the DC power received from the rectifier to be constant, an inverter configured to convert the DC power received from the smoothing filer into high-frequency power by turning the DC power on and off using a switching device made of an SiC semiconductor, and a control unit configured to control the rectifier and the inverter. A rating of output power output from the inverter is determined in accordance with a frequency of the high-frequency power output from the inverter, a current-applying time, and an operation rate obtained by dividing the current-applying time by a sum of the current-applying time and a non-current-applying time.

Abstract: A first switching element and a second switching element are thermally connected to each other since the first switching element and the second switching element are fixed on a second substrate. An upper arm is capable of increasing the current capacity of the semiconductor device because of the parallel connection of the first switching element and the second switching element. The lower arm is capable of increasing the current capacity of the semiconductor device because of the parallel connection of the first switching element and the second switching element.

Abstract: A method for controlling a back-to-back three-phase three-level converter having a grid-side AC/DC converter and a machine-side DC/AC converter connected by a split DC link which defines a DC link midpoint. The method includes controlling the grid-side converter to convert AC power from a grid into DC power of the DC link, controlling the machine-side converter to convert DC power from the DC link to AC power to feed a low frequency machine, and concurrently performing common mode voltage injection for the machine-side converter so as to at least partially compensate midpoint voltage ripple caused by the machine-side converter. The method further includes performing common mode voltage injection for the grid-side converter so as to at least partly further compensate the portion of the midpoint voltage ripple which remains uncompensated by controlling the machine-side converter. A control system implementing the control method and a power conversion system utilizing same.

Abstract: According to one aspect, embodiments of the invention provide a UPS comprising a plurality of DC busses configured to receive DC power from a converter, the plurality of DC busses including a positive DC bus configured to maintain a positive DC voltage level, a mid-point DC bus, and a negative DC bus configured to maintain a negative DC voltage level, a 3-level inverter coupled to the plurality of DC busses and configured to convert the DC power from the plurality of DC buses into output AC power, and a controller configured to monitor the positive and negative DC voltage levels, identify an imbalance between the positive and negative DC voltage levels, and selectively control, based on the imbalance, the 3-level inverter to operate in a 2-level mode of operation and a 3-level mode of operation to transfer energy between the positive and negative DC busses.

Abstract: An electric-power converting device having an inverter circuit of a 4-parallel configuration is realized by a combination of four first to third power semiconductor module devices. In each of module device groups, a single unit of the first power semiconductor module device and a single unit of the second power semiconductor module device are mixedly disposed so as to be alternately disposed. Furthermore, the first to third power semiconductor module devices have circuit element groups which have a common point that each circuit element group includes at least one of first and second transistors and first and second diodes.

Abstract: A method and controller for controlling a converter are provided. The converter is operated in a first phase in which controller logic asserts a first gate drive signal to cause a first transistor of the converter to be conductive and deasserts a second gate drive signal to cause a second transistor of the converter to be non-conductive. In a first deadtime phase and a second phase, the controller logic deasserts both the first and second gate drive signals to cause leakage energy from a leakage inductance of a primary winding of the converter to be transferred to a clamp capacitance of the converter. After the leakage energy is transferred, the converter is operated in a third phase in which the logic asserts the second gate drive signal and deasserts the first gate drive signal.

Abstract: In order to set the output voltage of a resonant converter to a desired value by means of a simple additional circuit while the resonant converter is in open circuit operation, it is intended that at least one capacitor each (C1, C2) is connected in parallel to the electrical switching elements (S1, S2) of the secondary side of the resonant converter (1).

Abstract: An insulation type step-down converter includes first and second step-down transformers each of which includes an input-side coil and an output-side coil. First, second, third, and fourth rectifier elements are connected in series with first, second, third, and fourth series coils, respectively, the first, second, third, and fourth series coils each having the output-side coil of the first step-down transformer and the output-side coil of the second step-down transformer connected in series. The first to fourth series coils are connected to smoothing coils. The connection is such that electric currents flow simultaneously only in one of the first and second series coils and one of the third and fourth series coils in an alternate manner, and electric currents flowing simultaneously in one of the first and second series coils and one of the third and fourth series coils are opposite in direction to each other.

Abstract: A circuit includes first and second half bridges, a first inductor, a second inductor, and a main inductor. The half bridges each include a high side switch, a low side switch, and a gate driver configured to apply switching signals to the high side switch and the low side switch. The first inductor has one side electrically connected to an output node of the first half bridge between the high side switch and the low side switch. The second inductor has one side electrically connected to an output node of the second half bridge between the high side switch and the low side switch. The main inductor is coupled to a node between the other sides of the first and second inductors. The main inductor has a greater inductance than each of the first and second inductors, and the first and second inductors are inversely coupled to one another.