Abstract: Transistor devices are described that include a first transistor and a second transistor coupled in parallel between a first terminal and a second terminal. The second transistor is based on a wide bandgap semiconductor material. The second transistor has a breakthrough voltage lower than a breakthrough voltage of the first transistor over a predetermined operating range. The predetermined operating range comprises at least an operating range for which the transistor device is specified.

Abstract: When a vehicle approaches a parking space, a ground controller sets a power transmission coil to first excitation in which the power transmission coil is excited in an excitation pattern containing identification data. A vehicle controller pre-charges a capacitor connected to a power reception coil after the vehicle approaches the parking space. Further, the vehicle controller acquires the identification data when the power transmission coil is in the first excitation, and transmits the acquired identification data to the ground unit. The ground controller pairs a power transmission device and a power reception device with each other if the identification data contained in the excitation pattern and the identification data acquired by the vehicle controller match each other.

Abstract: A power supply system of an embodiment has a plurality of power conditioners, an acquisition device, and a search instruction generator. The power conditioners convert a form of electrical power generated by a plurality of electrical generators into a different form of electrical power. The acquisition device acquires a respective information regarding power output from each of the plurality of power conditioners. The search instruction generator generates and outputs an operating point search instruction to one or more power conditioners being lower in a ratio of output power with respect to a reference power by at least a prescribed degree than one or more different power conditioners, wherein the reference power is given, based on the maximum output power or rated power of the corresponding electrical generator, or based on the maximum output power or rated power of the power conditioner.

Abstract: There is provided a composite material containing magnetic powder and a polymeric material including the powder in a dispersion state, wherein a content of the magnetic powder with respect to the whole composite material is more than 50% by volume and 75% by volume or less, a saturation magnetic flux density of the composite material is 0.6 T or more, and a relative magnetic permeability of the composite material is more than 20 and is 35 or less. It is preferable that a density ratio of the magnetic powder should be 0.38 or more and 0.65 or less. The density ratio is set to be an apparent density/a true density. Moreover, it is preferable that the magnetic powder should include a plurality of particles constituted of the same material.

Abstract: Disclosed are a power conversion device and a photovoltaic module including the same. The power conversion device includes a full-bridge switching unit including first to fourth switching elements, a first transformer having an input terminal connected between the first switching element and the second switching element in the full-bridge switching unit and an output terminal connected between the third switching element and the fourth switching element in the full-bridge switching unit, wherein the first switching element is serially connected to the second switching element, and the third switching element is serially connected to the fourth switching element, and a second transformer connected to the full-bridge switching unit as a half-bridge, wherein the full-bridge switching unit coverts a first DC power input to the first transformer into a first alternating current AC waveform, based on variable duty switching.

Abstract: A switching power supply includes a SiC MOSFET (a main switching device) that switches a main current flowing through a primary coil of a transformer ON and OFF as well as a Si MOSFET (a secondary switching device) that has a lower power capacity than the main switching device and is arranged in parallel therewith. A control circuit includes a driver circuit that respectively switches the main switching device and the secondary switching device ON and OFF on the basis of a control signal generated in accordance with an output voltage obtained from a secondary coil of the transformer. The control circuit further includes an enable control circuit that disables the ON/OFF switching of the main switching device when a voltage of an auxiliary voltage obtained from an auxiliary coil of the transformer is less than a prescribed threshold voltage.

Abstract: An inverter-control element operates with a power-supply potential supplied to an inverter-control-system power-supply terminal to output a signal for controlling an inverter switching element. A brake control element operates with a power-supply potential supplied to a brake-control-system power-supply terminal to output a signal for controlling a brake switching element. A first metal component includes a plurality of protrusions protruding from a sealing resin, is supported by the sealing resin with a portion embedded in the sealing resin, and is electrically connected to each of the inverter-control-system power-supply terminal and the brake-control-system power-supply terminal.

Abstract: A DC-DC converter includes a voltage input portion that receives a DC voltage, a voltage output portion to which a load is connected, a transformer that includes at least a primary winding and a secondary winding, a main switch element between the voltage input portion and the primary winding of the transformer, a rectifier circuit between the voltage output portion and the secondary winding of the transformer, and a reset voltage suppressing circuit that detects a magnitude of a reset voltage generated when excitation energy accumulated in the transformer is reset and reduces a voltage which is applied to the main switch element when the magnitude of the reset voltage exceeds, for example, a predetermined threshold value.

Abstract: In electric equipment, a switching substrate is provided along winding axes of winding parts. A part of the switching substrate is overlapped with a reactor, as viewed in a direction perpendicular to a virtual plane including the winding axes. Further, an electric current sensor is shifted from the reactor in a direction of winding axes, and a sensor substrate is provided in parallel to the virtual plane.

Abstract: A method for reducing electromagnetic interference in a flyback converter includes activating a first switch to generate a primary current therein. The first switch is deactivated to generate a secondary current from a magnetic flux generated by the primary current. The magnetic flux is removed by the generation of the secondary current. A second switch is activated with a first voltage pulse to limit an excess voltage across the first switch. The excess voltage is generated in response to the deactivation of the first switch. A second switch is activated with a second voltage pulse to limit a voltage oscillation across the first switch. The voltage oscillation occurs after the removal of the magnetic flux. A first pulse width of the first voltage pulse is increased by a first jitter delay. A second pulse width of the second voltage pulse is increased by a second jitter delay.

Abstract: The present invention is provided with a power converter and a control device for controlling the power converter, wherein each of the positive arm and the negative arm is comprised one converter cell or a plurality of converter cells connected in series, each converter cell being comprised: a series unit in which a plurality of switching elements are connected in series to each other; and a DC capacitor connected in parallel to the series unit, and the control device includes a DC voltage command value calculation unit which calculates a voltage command value for outputting, during a DC short circuit fault, AC voltage similar to that in a steady state to the AC terminal of the power converter, and for outputting, to the DC terminal of the power converter, DC voltage that allows the protection relay in the DC line to operate.

Abstract: Various embodiments of apparatuses, systems, and methods for controlling the operating status of a power converter during, a standby mode, a powered mode, and a transition from the standby mode to the powered mode is described. For at least one embodiment, a power converter includes a primary controller and a secondary controller wherein the primary controller includes a first circuit configured to initiate a transition from standby mode to powered mode upon receipt of a wake-up signal and wherein the first circuit is powered during standby mode. For at least one embodiment, the first circuit is powered during a transition from a standby mode to a powered mode by voltages induced in a third coil of a transformer by a device battery powering a second coil of the transformer. For one embodiment, an IMIN controller is utilized to control output currents during transitions from standby to powered mode.

Abstract: First and second element pairs formed by connecting FWDs and MOSFETs in antiparallel are connected in series and sealed by resin to configure a core module. In the core module, a first drain electrode, a first source electrode, a second drain electrode, and a second source electrode are exposed to the surface. A cover with terminals is put on the core module. At this time, each of the direct-current positive electrode terminal, the direct-current negative electrode terminal, and the alternating-current terminal of the cover with terminals is electrically connected to each of the first drain electrode, the second source electrode, and the first source electrode and the second drain electrode.

Abstract: A dynamic impedance system deployable on a current transformer having a core and at least one winding element is provided. The dynamic impedance system includes a voltage reference module and a dynamic impedance module operably connected to one another. The voltage reference module defines a voltage threshold for regulating an output voltage of the current transformer. The dynamic impedance module regulates the output voltage based on the voltage threshold defined by the voltage reference module to maintain flux induced in the current transformer, thereby avoiding core saturation of the current transformer and enhancing accuracy of measurements.

Abstract: A physical topology for receiving top and bottom power electronic switches comprises a top collector trace connected to a positive voltage power supply tab and having a connection area for a collector of a top power electronic switch, a bottom emitter trace connected to a negative voltage power supply tab and having a connection area for an emitter of the bottom power electronic switch, and a middle trace connected to a load tab and having a connection area for an emitter of the top power electronic switch and a connection area for a collector of the bottom power electronic switch. Sampling points are provided on the traces for voltages on the emitters of the top and bottom power electronic switches, on the trace for voltage of the collector of the bottom power electronic switch, and on the negative voltage power supply tab. The topology defines parasitic inductances.

Abstract: A vehicle may include an electric drive system including switches having gates configured to control the switches. The vehicle may include a galvanic isolation coupling having a primary side electrically connected with an input power source and a secondary side electrically connected with a gate driver circuit. The gat driver circuit has a controller configured to actuate the gates and a power supply circuit electrically connected to the controller to provide backup power. The galvanic isolation coupling may be a flyback converter.

Abstract: An outphasing amplifier includes a first class-E power amplifier having an output coupled to a first conductor and an input receiving a first RF drive signal. A first reactive element is coupled between the first conductor and a second conductor. A second reactive element is coupled between the second conductor and a third conductor. A second class-E power amplifier includes an output coupled to a fourth conductor and an input coupled to a second RF drive signal, a third reactive element coupled between the second and fourth conductors. Outputs of the first and second power amplifiers are combined by the first, second and third reactive elements to produce an output current in a load. An efficiency enhancement circuit is coupled between the first and fourth conductors to improve power efficiency at back-off power levels. Power enhancement circuits are coupled to the first and fourth conductors, respectively.

Abstract: A phase leg for a multilevel inverter includes a first direct current lead, an outer solid-state switch, an inner solid-state switch, and a midpoint-clamping device. The outer solid-state switch device is connected to the first direct current lead. The inner solid-state switch is connected in series with the outer solid-state switch. The midpoint-clamping device is a bi-directional current flow device connected between a second DC lead and a node between the inner and outer solid-state switches for reducing conduction losses associated with current flowing through the phase leg.

Abstract: Methods and systems for controlling an electric motor are provided. An electric motor controller is configured to be coupled to an electric motor. The controller includes a rectifier, an inverter coupled to the rectifier, and a control unit coupled to the inverter. The rectifier is configured to rectify an alternating current (AC) input voltage to produce a pulsed direct current (DC) voltage that drops to approximately zero during each cycle when the AC input voltage transits zero. Energy is stored on a load coupled to the motor when AC input voltage is available. The inverter is configured to receive the DC voltage and to provide a conditioned output voltage to the motor. The control unit is configured to manage energy transfer between the motor and the load such that the motor generates positive torque when the DC voltage supplied to the inverter has approximately 100% voltage ripple.

Abstract: A power supply for welding, cutting and similar operations includes a dual two-switch forward converter. The converter has two inverter circuits coupled in parallel but controlled to provide output power in an interleaved fashion. To avoid “walking” of the circuits (which could result in different duty cycles and imbalance of the load sharing), control signals are determined and applied to a first of the inverter circuits, and “on” times of the first circuit is monitored, such as by augmenting a counter to determine the number of clock cycles the first circuit is “on”. The same duration is then used for commanding output from the second inverter circuit. The duty cycles of both circuits is thus ensured to be the same regardless of changes in the total output power.

Abstract: A power converter controller includes a primary controller configured to operate in a first mode to control a power switch with a primary switching pattern. A communication link is coupled to the primary controller. A secondary controller coupled to the communication link. The secondary controller is galvanically isolated from the primary controller. The secondary controller is configured to initiate a transition operation with the primary controller to take control of the power switch with one or more control signals through the communication link. The primary controller is configured to acknowledge receipt of the one or more control signals through the communication link to the secondary controller and transition from the first mode to a second mode.

Abstract: Feedback-type control systems for power converters that assist the power converters in staying within operational limited during disturbances. In some embodiments, each control system includes an impedance current regulator controlled as a function of an error between a measured feedback voltage signal representing the output of the power converter and an active feedforward voltage signal. In some multiphase embodiments, the impedance current regulator includes a gain that is adjusted as a function of the level of phase imbalance among the multiple phases. In some multiphase embodiments, a total current limit is determined as a function of the level of phase imbalance among the multiple phases. Corresponding feedback control methods and software, as well as power converter systems and AC network systems incorporating such feedback control systems, are also disclosed.

Abstract: An apparatus for measuring volume flow of a fluid flowing through a measuring tube in the direction of its longitudinal axis, comprising a coil arrangement, at least two measuring electrodes coupling with the fluid and a control/evaluation unit, which in connection with the coil arrangement produces a magnetic field periodically changing its polarity and extending essentially transversely to the longitudinal axis of the measuring tube. The control/evaluation unit during a measuring phase at an essentially constant magnetic field determines the volume flow of the fluid in the measuring tube based on a voltage induced in the measuring electrodes. The control/evaluation unit supplies the coil arrangement with an overvoltage during a delay phase, and the delay phase begins at the point in time of the reversal of the polarity of the magnetic field and ends at the point in time of the beginning of the measuring phase.

Abstract: An inverter circuit provided in a power conversion device includes a full-bridge inverter, and a short circuit part. The short circuit part includes switching elements and clamp elements connected to the switching elements. The clamp elements suppress application of an excessive voltage such as a surge voltage to the switching elements.

Abstract: The present invention provides an active-clamp flyback circuit and a control method thereof. The active-clamp flyback circuit includes a flyback switching power supply, and further includes a first capacitor and a first switch tube. One end of the first capacitor is connected with a high potential end of an input power supply, the other end is connected with a first end of the first switch tube, and a second end of the first switch tube is connected with a common end of the main power switch tube and the primary winding. A turn-off moment of the first switch tube is adjusted according to time when the main power switch tube is turned on and the first switch tube is turned off and voltages at both ends of the magnetizing inductor. The present invention can reduce the turn-on loss of the main power switch tube.

Abstract: A voltage converter may include a first set of silicon (Si)-based power devices coupled to a first direct current (DC) voltage source and a second set of Si-based power devices coupled to a second DC voltage source. The voltage converter may also include a first set of silicon-carbide (SiC)-based power devices coupled to the first set of Si-based power devices and to the second set of Si-based power devices. Each SiC-based power device of the first set of SiC-based power devices may switch at a higher frequency as compared to each Si-based power device of the first and second sets of the Si-based power electronic devices.

Abstract: A powertrain for a vehicle includes a DC/DC converter and a controller. The DC/DC converter includes an inductor and output capacitor and is coupled between a traction battery and an electric drive unit. The controller may be configured to, in response to an electrical connection between the vehicle and an AC grid, couple the output capacitor and inductor in series and across terminals of the traction battery to absorb reactive power from the AC grid.

Abstract: A control device is applied for a power supply system that includes two boost converters. The two boost converters boosts inputted direct-current voltages to predetermined output voltages and output ends of the two boost converters are connected in parallel with each other. The control device includes a switching portion and a control portion. The switching portion controls switching of a switching element included in each of the two boost converters. The control portion shifts switching timings of the switching elements of the two boost converters from each other.

Abstract: A semiconductor device includes a first circuit board on which a first switching element and a first diode connected in inverse parallel are mounted, a second circuit board on which a second switching element and a second diode connected in inverse parallel are mounted, a printed circuit board disposed opposite the first circuit board and the second circuit board, and a plurality of conductive posts which electrically connect the first switching element, the second switching element, the first diode, the second diode, the first circuit board, or the second circuit board and metal layers of the printed circuit board. The first switching element and the second switching element are connected in anti-series to form a bidirectional switch.

Abstract: A method and corresponding system for operating an inverter includes setting an input voltage (UPV) of the inverter by an input-side DC-DC converter and/or an output-side inverter bridge, wherein the input voltage (UPV) corresponds to an MPP voltage (UMPP) at which a generator connectable on the input side outputs a maximum electrical power, and determining a first temperature value (TDCDC) in the DC-DC converter and a second temperature value (TDCAC) in the inverter bridge.

Abstract: A buck converter includes a power switch having one end to which an input voltage is transferred, a synchronous switch connected between the other end of the power switch and the ground, an inductor having an end connected to the other end of the power switch, and a switch control circuit configured to calculate a zero voltage delay time based on at least an ON time of the power switch and a delay time. The delay time is determined based on the inductor and parasitic capacitors of the power switch and the synchronous switch.

Abstract: In a control device controlling a drive circuit that drives an in-vehicle electric motor based on an output voltage of a DC power source, a capacitor for stabilizing the output voltage is disposed between the DC power source and the drive circuit, and a relay switch is disposed between the DC power source and the capacitor. The control device includes: an anomaly determining device that determines whether an anomaly occurs in a vehicle; and a discharge control device that controls the drive circuit to generate a torque at the electric motor based on an output voltage of the capacitor in a state where the relay switch disconnects between the DC power source and the capacitor when the anomaly determining device determines that the anomaly occurs in the vehicle.

Abstract: A flyback power converter includes a hybrid clamp circuit and a corresponding power management unit that substantially optimizes the performance of the flyback power converter in its entire line and load ranges. The clamp circuit, which is connected in parallel to a primary winding of the flyback transformer, includes a parallel combination of a capacitor and resistor that is connected in series with a parallel combination of a switch and a diode. By sensing the operating conditions, the power management circuit configures the clamp circuit either as a passive clamp or as an active clamp. In the passive-clamp configuration, the switch is kept turned off. In the active-clamp configuration, the switch operates with pulse-width modulation (PWM) which enables ZVS turn-on of the main switch.

Abstract: The present disclosure discloses a charging system and method, and a power adapter. The system includes a power adapter and a terminal. The power adapter includes a first rectifier, a switch unit, a transformer, a synthesizing unit, a sampling unit, and a control unit. The control unit outputs a control signal to the switch unit, and adjusts a duty ratio of the control signal according to a current sampling value and/or a voltage sampling value, such that a second alternating current outputted by the synthesizing unit meets a charging requirement. The terminal includes a battery.

Abstract: In a power receiving device, a module including a power receiving unit, a transformer, a filter circuit and a rectifier circuit includes a coil and a capacitor. An alternating-current power supply unit is configured to be able to supply alternating current to the power receiving device on a side closer to the power receiving unit than a relay. A vehicle electronic control unit is configured to, when alternating current is supplied from the alternating-current power supply unit in a case where the relay is turned off, detect whether there is an abnormality in at least one of the coil or the capacitor on the basis of a detected value of a current sensor.

Abstract: A power conversion circuit has a controller with an input terminal and a circuit configured to drive an electric current out of the input terminal in response to a condition of the controller. An indicator is coupled to the input terminal of the controller. The controller includes a clock signal controlling the electric current out of the input terminal. The input terminal is a voltage sensing terminal or feedback input terminal in some embodiments.

Abstract: In an embodiment, a circuit for a Direct Current to Direct Current (DC-DC) converter comprises an input voltage detection circuit, an oscillator circuit, and a burst entry detection circuit. The input voltage detection circuit produces, using a voltage sense signal, a first input voltage indicator. The first input voltage indicator indicates a voltage range selected from a plurality of voltage ranges. The oscillator circuit selects, using the first indicator, a foldback curve from a plurality of foldback curves. The foldback curve is used to determine a blanking time of a gate signal. The burst entry detection circuit determines, using an indicator of an output power of the DC-DC converter, whether to operate the circuit in a burst mode.

Abstract: In some embodiments, an inductor-inductor-capacitor (LLC) converter includes a transformer having a primary winding, a secondary winding, and an auxiliary winding. The primary winding is coupled to a primary side circuit and the auxiliary winding has a first winding portion coupled between a first terminal and a middle terminal, and a second winding portion coupled between the middle terminal and a second terminal. The LLC converter further includes a first diode coupled between the first terminal and a first node, a second diode coupled between the second terminal and the first node, and a switch coupled between the first node and a reference voltage terminal. The middle terminal of the auxiliary winding is coupled to the reference voltage terminal.

Abstract: The combined voltage regulator and snubber circuit generally has a voltage regulator device in parallel with the energy storage element of the snubber circuit operatively connectable in series with a leakage inductance current path; the leakage inductance being part of a magnetic component utilized in a switch-mode power supply having an input voltage source, controllable semiconductor switches, freewheeling semiconductor switches, feedback controller, reactive energy storage components and a load; the voltage regulator generally providing constant or variable voltage to the gate driver of the controllable semiconductor and/or feedback controller; the snubber circuit generally recycling leakage inductance energy to the input capacitor of a neighboring cell in a multi-cell stacked converter.

Abstract: A transformer includes a front stage circuit and a rear stage circuit. As a front stage circuit, a switch series unit, which is connected in parallel to a power supply, includes odd-numbered switches and even-numbered switches alternately turned ON. Mutual connection points of the respective switches and points at both ends of the switch series unit are regarded as m nodes in total. Capacitors are provided on at least one of a first electrical path combining odd nodes to lead them to a first output port, and a second electrical path combining even nodes to lead them to a second output port. The capacitors are present so as to correspond to at least (m?1) nodes. The rear stage circuit includes an element series unit, which is composed of a pair of semiconductor elements connected in series to each other for conducting operations of mutually opposite polarities, and necessary inductors.

Abstract: Disclosed herein are systems and methods for estimating a period and frequency of a waveform. In one embodiment a system may comprise an input configured to receive a signal comprising a representation of the waveform. A period determination subsystem may calculate an estimated period of the signal based on a period determination function. An estimated period adjustment subsystem may determine an adjustment to the estimated period based on a result of the period determination function. A quality indicator subsystem configured to evaluate a measurement quality indictor function based on the estimated period, and to selectively update the period of the waveform based on the measurement quality indicator. A control action subsystem configured to implement a control action based on the period of the waveform.

Abstract: A Synchronous Rectifier (SR) controller circuit includes a dead time evaluation circuit, an offset voltage controller circuit, an off threshold control circuit, and a comparator circuit. The dead time evaluation circuit produces an indication of whether a measured dead time of an SR switching device is less than a target dead time. The offset voltage controller circuit determines an offset count using the indication, an offset voltage using the offset count, and high and low saturation indicators according to the offset count. The off threshold control circuit determines a threshold count using the high and low saturation indicators and an off threshold voltage using the threshold count. The comparator circuit determines whether a measured voltage of the SR switching device is greater than a virtual off threshold voltage, the virtual off threshold voltage corresponding to the off threshold voltage minus the offset voltage.

Abstract: A device for safe control of at least one driver module for controlling a semiconductor switch of an inverter, wherein the driver module controls the semiconductor switch in dependence on a pulse signal, wherein a switching arrangement which is connected with the driver module is provided and that this has a switching connection for applying an inhibition signal and a first connection for applying the pulse signal, in order to either inhibit or switch the pulse signal applied to the first connection through to the driver module depending on the inhibition signal.

Abstract: A biasing circuit for a flyback converter can include a rectifier electrically coupled to an inductor of the flyback converter for generating a direct current signal from an alternating current signal outputted by the inductor in response to the inductor transferring an amount of energy to another inductor. The biasing circuit can also include a storage device electronically coupled to the rectifier to receive the direct current signal and store a charge. The biasing circuit can further include a limiting device electronically coupled to the storage device to provide an amount of the charge that is stored in the storage device to an input lead of a switch of the flyback converter for biasing the switch.

Abstract: A power conversion apparatus includes a first semiconductor element pair that includes a MOSFET made of wide bandgap semiconductor material and a wide bandgap diode made of wide bandgap semiconductor material which is reverse parallel-connected to the MOSFET, a second semiconductor element pair that includes an IGBT made of silicon semiconductor material and a silicon diode made of silicon semiconductor material which is reverse parallel-connected to the IGBT, and a control circuit section for controlling switching operation of the MOSFET and the IGBT. The first and second semiconductor element pairs are connected in series to each other.

Abstract: In a described example, an apparatus includes a first switch coupled between a terminal for receiving an input voltage and a top plate node, and having a first control terminal; a second switch coupled between the top plate node and a switching node, and having a second control terminal; a third switch coupled between the switching node and a bottom plate node and having a third control terminal; a fourth switch coupled between the bottom plate node and a ground terminal, and having a fourth control terminal; a flying capacitor coupled between the top plate node and the bottom plate node; a fifth switch coupled between the top plate node and an auxiliary node; a sixth switch coupled between the auxiliary node and the bottom plate node; and an auxiliary capacitor coupled between the auxiliary control terminal and a ground terminal.

Abstract: An electric power converter performing power conversion includes a plurality of semiconductor modules with built-in semiconductor elements, a plurality of cooling tubes stacked together with the plurality of semiconductor modules, and a pressure member made of metal. The pressure member has a pressing surface for pressing an outer cooling tube in order to press-contact the plurality of cooling tubes and the plurality of semiconductor modules in a stacking direction, and a heat receiving surface that receives heat generated from a capacitor that is an electronic component which is different from the plurality of semiconductor modules, by thermal conduction.

Abstract: In a push-pull type DC/DC converter capable of operating primary side switching elements alternately, a switching operation section turns on a primary side switching element having a high priority after a mode (d) as a normal state is transferred to a mode (d) as an inverse state during a circulation period when a load current is circulated into the secondary side rectifier elements when all of the primary side switching elements are turned off. To turn on the primary side switching element having a high priority after occurrence of the state transition to the inverse state can reduce a voltage immediately after supplying of electric power to the primary side switching elements with using exciting current and without adding any additional component.

Abstract: A ultra-high power ZVS+ZCS integrated soft switching DC/DC converter is disclosed, which adopts a phase shifted full bridge ZVS (zero voltage switching) DC/DC converter circuit. A saturation inductance Lk=Lk1+Lk2 controlled by a load current is series connected to a primary side of a high permeability ring transformer. A RCD buffer circuit for ZCS (zero voltage switching) current zero-crossing switching off is connected to a secondary side of the transformer. When a lead arm commutates, a refringence of a load current is blocked; the ZVS (zero voltage switching) is ensured; exciting current disappears; a lag arm realizes ZCS zero current commutating. The controlled inductance LK assists to establish a corresponding load refringenced current and the exiting current and recovers electromagnetic induction; The RCD buffer circuit softens the reverse current of bridge rectifier and oscillations caused by the leakage inductance on secondary side of the transformer and the buffer capacitor are attenuated.

Abstract: The present invention generally relates to a switching cell for a phase leg of a power converter and a method of controlling a power converter to drive a load, and more particularly to a plurality of such switching cells, a phase arm for a power converter, a power converter phase leg, to a power converter for driving a load, and methods of making a power converter.