Abstract: A device comprises a switch network coupled to a power source, wherein the switch network comprises a plurality of power switches, a transmitter resonant tank coupled to the plurality of power switches, wherein the transmitter resonant tank comprises a primary resonant capacitor, a transmitter coil coupled to the transmitter resonant tank and a harmonic reduction apparatus coupled between the switch network and the transmitter coil, wherein the harmonic reduction apparatus is configured to attenuate at least one undesired frequency component.

Abstract: A power converter comprises a primary switch network coupled to a power source, wherein the primary switch network comprises a plurality of power switches, a controller configured to generate gate drive signals for the plurality of power switches, a secondary rectifier coupled to an output, a first transformer having a first winding coupled to the primary switch network, a second winding coupled to the secondary rectifier and a third winding coupled to the controller and a second transformer having a fourth winding coupled to the primary switch network, a fifth winding coupled to the secondary rectifier and a sixth winding coupled to the controller, wherein a voltage signal from the third winding and/or the sixth winding is processed to provide a feedback of a voltage at the output.

Abstract: A system comprises a power amplifier configured to receive a frequency control signal, wherein the frequency control signal is generated based upon a system clock of a communication device and the frequency control signal is used to control a switching frequency of the power amplifier and a first resonant circuit coupled between the power amplifier and a first coil, wherein the first resonant circuit comprises a first variable capacitance network.

Abstract: A system comprises a primary switch network coupled to a power source, wherein the primary switch network comprises a plurality of power switches, a primary resonant tank coupled to the plurality of power switches, wherein a resonant capacitor of the primary resonant tank is formed by a first variable capacitance network, and wherein the first variable capacitance network is modulated to improve soft switching of the plurality of power switches through reducing a voltage level and a current level of a switch at a turn-on instant and a primary coil coupled to the primary resonant tank.

Abstract: An embodiment apparatus comprises a secondary synchronous rectifier and a secondary gate drive controller coupled to a transformer winding. The secondary gate drive controller is configured to generate a forward gate drive signal for the forward switch and generate a freewheeling gate drive signal for the freewheeling switch, wherein the secondary gate drive controller generates a dead time between the forward gate drive signal and the freewheeling gate drive signal.

Abstract: A device has a plurality of power converter groups and a control system. A power converter group has a group of power converters and is coupled between an input voltage source and a group of windings of a motor generator. The control system is configured to control currents of the windings such that the number of poles of and the number of phases in a pair of poles of the motor/generator are dynamically adjusted, and the number of poles and the strength of a magnetic field of the motor generator are controlled to reduce a power loss. The motor/generator has an air gap and a stator with a plurality of slots, where the windings are installed in. The windings are configured such that the number of poles and the number of phases in a pair of poles of the motor/generator can be dynamically adjusted.

Abstract: A method includes coupling a primary side circuit of a resonant power system to a secondary side circuit, wherein the primary side circuit comprises a first resonant tank comprising a first variable capacitance network having a first resonant frequency and the secondary side circuit comprises a second resonant tank having a second resonant frequency and modulating a capacitance of the first variable capacitance network to adjust an operation parameter of the resonant power system.

Abstract: An apparatus comprises a first capacitor and a second capacitor connected in series, a diode and the second capacitor connected in parallel, wherein a cathode of the diode is connected to a common node of the first capacitor and the second capacitor and a plurality of adjustable capacitance networks connected in parallel with the second capacitor.

Abstract: A device comprises a motor/generator having an air gap and a plurality of windings, a plurality of power converter groups, and a control system. The windings are so configured that the number of phases in a pair of poles and the number of poles of the motor/generator can be dynamically adjusted. The power converter group comprises a plurality of power converters which is coupled between an input voltage source and a plurality of windings for controlling currents in the windings. The control system is so configured such that the number of poles of the motor/generator and the number of phases in a pair of poles are dynamically adjusted, and a synchronous speed of a moving magnetic field generated by winding currents within first pair of poles is approximately equal to a synchronous speed of a second moving magnetic field generated by currents in the windings within second pair of poles.

Abstract: An apparatus comprises a sense transistor having a gate and a source directly connected to a gate and a source of a power transistor of a resonant converter respectively, wherein the resonant converter comprises a primary side and a secondary side magnetically coupled to the primary side, a current sense and amplification circuit comprising an amplifier having inputs connected to a drain of the sense transistor and a drain of the power transistor respectively, an analog-to-digital converter connected to an output of the current sense and amplification circuit and a digital controller connected to an output of the analog-to-digital converter, wherein the digital controller is configured to modulate a variable capacitance network of the resonant converter based upon a current flowing through the sense transistor.

Abstract: A structure comprises a plurality of first turns of a coil and a plurality of second turns of the coil having a similar shape as the plurality of first turns of the coil, wherein the plurality of first turns of the coil and the plurality of second turns of the coil have a similar center position and a current flowing through the plurality of first turns of the coil and a current flowing through the plurality of second turns of the coil are in opposite directions.

Abstract: A power converter comprises a switch network coupled to an input voltage, a power transformer having a primary winding and a secondary winding, wherein the primary winding is coupled to the switch network, and the secondary winding is coupled to a rectifier, wherein the rectifier is coupled to an output voltage, a primary resonant tank having a first resonant capacitor and a first resonant frequency, and coupled to the primary winding of the power transformer and the switch network, and a regulation circuit configured to control the output voltage of the power converter to be substantially proportional to the input voltage and the switch network to operate at a frequency substantially close to the first resonant frequency.

Abstract: An embodiment holdup time circuit of a bridgeless power factor correction circuit comprises a charge device connected between an output terminal of a bridgeless power factor correction circuit and an energy storage apparatus, a discharge device connected between the energy storage apparatus and an input of the bridgeless power factor correction circuit, the energy storage apparatus and the bridgeless power factor correction circuit comprising a first boost converter, a second boost converter, a first switch and a second switch, wherein the first switch is connected between the first boost converter and ground and the second switch is connected between the second boost converter and ground.

Abstract: A structure comprises a first portion of a winding having a first almost enclosed shape, a second portion of the winding having a second almost enclosed shape and a connection element between the first portion and the second portion, wherein the first portion and the second portion are arranged in a symmetrical manner and the first portion, the second portion and the connection element form a first air core inductor.

Abstract: An embodiment power converter package comprises a semiconductor die, an output inductor, a plurality of input capacitors and output capacitors. The semiconductor die, the output inductor and the plurality of capacitors are mounted on a lead frame and connected one to another through various pads on the lead frame. The semiconductor die comprises a high side switch, a low side switch and a driver. The power converter package is electrically coupled to an external pulse width modulation controller through a variety of input and output pads.

Abstract: A power system comprising a non-isolated voltage regulator configured to couple to an input voltage and produce an output voltage, wherein the non-isolated voltage regulator is in a power distribution system and configured to boost the input voltage when the input voltage is less than a minimum output voltage, to reduce the input voltage when the input voltage is greater than a maximum output voltage, and to pass-through the input voltage when the input voltage is greater than or equal to the minimum output voltage and less than or equal to the maximum output voltage.

Abstract: An embodiment holdup time circuit of a bridgeless power factor correction circuit comprises a charge device, an energy storage apparatus and a discharge device. The charge device comprises a first terminal coupled to a bridgeless power factor correction circuit and a second terminal coupled to the energy storage apparatus. The discharge device comprises a first terminal coupled to the energy storage apparatus and a second terminal coupled to the bridgeless power factor correction circuit.

Abstract: A multilevel LLC resonant converter comprises a first capacitor and a second capacitor connected in series providing a mid-voltage point of an input dc power source, a resonant tank connected in series with a primary side of a transformer, a first transistor and a second transistor connected in series, wherein a common node of the first transistor and the second transistor is connected to the mid-voltage point through a first isolation switch and a third transistor and a fourth transistor connected in series, wherein a common node of the third transistor and the fourth transistor is connected to the mid-voltage point through a second isolation switch.

Abstract: An apparatus for controlling a motor/generator having a plurality of windings comprises a stator magnetically coupled to a rotor and having a plurality of slots and a plurality of windings, a controller and a power converter means. Each winding is installed in two corresponding slots, and a plurality of magnetic poles and a plurality of phases in each pair of poles are formed when currents flow through the windings, and the windings are configured such that the number of phases and the number of poles can be dynamically. The controller comprises a pole and phase mapping for controlling the winding of the motor/generator to a pole and a phase, and a phasor control for controlling currents of the windings such that the number of poles of the motor/generator and the number of phases in a pair of poles are dynamically adjusted through a phase relationship between the currents of the windings. The power converter means is controlled by the controller for controlling the winding currents of the motor/generator.

Abstract: A device to drive a plurality of power switches in a power converter with an input voltage port having an input voltage comprises a drive resonant tank, a switch network, a control block configured to control the turn-on and turn-off of drive switches, and an output port. The drive resonant tank comprises a resonant inductor, and a resonant capacitor which comprises an input capacitance of a power switch. The switch network has a plurality of drive switches, which are controlled such that the drive resonant tank goes through a resonant state and a pseudo clamp state consecutively during a switching period. A gate drive voltage of a power switch fluctuates slightly during the pseudo clamp state. The output port has two terminals coupled to a gate and a source of a power switch respectively.