Virginia Tech Intellectual Properties, Inc.

Nissan Motor Company Limited

Khai Doan The Ngo

Shigeharu Yamagami

Rengang Chen

Hui Wang

Ting Ge

Han Cui

Xiao Cao

Yin Wang

Cong Tu

The present invention is directed to a compact inductor having the required (predetermined) inductance and current rating, further designed to avoid substantial heat generation by avoiding saturation, winding(s) possessing a low DC resistance and copper loss, and minimizing the required volume or profile in order to conserve circuit board real-estate. The compact inductor design of the present invention includes both enclosed core as well as enclosed winding type of inductor designs.

Compact inductor employing redistributed magnetic flux

Aspects of series resonator DC-to-DC converters are described. A series resonator DC-to-DC converter can include a first half-bridge circuit comprising a first high-side switch and a first low-side switch, a second half-bridge circuit comprising a second high-side switch and a second low-side switch, and a resonator in series between the first high-side switch and the first low-side switch. The circuit design and switching controller can be relied upon to impart soft-switching.

Series resonator converter

A power converter is basically provided with at least three switching circuits, at least one power source, at least one load, and a resonant circuit. Input terminals of the switching circuits are connected to either the at least one power source or the at least one load, and output terminals of the switching circuits are electrically serially connected to the resonant circuit to form a closed circuit.

DC-DC power converter

Switches of a switching circuit used to control operation of an electric motor such as in an electrically powered vehicle connect respective windings of the electric motor as a single phase inductor during battery charging. The inductor can then store inherent low frequency, second order ripple power and return that power to a load presented by a battery during battery charging to deliver substantially constant current. Storage of ripple power in the inductor allows the capacitance value, size, weight and cost of a filter capacitor of a power factor correction circuit providing input power to a battery charger to be reduced by an order of magnitude or more. Direction of current flow through the inductor is periodically reversed to avoid magnetizing the motor.

Energy storage for power factor correction in battery charger for electric-powered vehicles

A power converter including a resonant circuit is controlled by pulse width modulation (PWM) of a switching circuit to control current in the resonant circuit near the frequency of the resonant circuit (a null-immittance criterion) in order to control current and voltage at the output of the resonant circuit. Further control of voltage can be performed by PWM of a switching circuit at the output of the resonant circuit such that centers of the duty cycles of respective switches for the output of the resonant circuit are substantially synchronized and substantially symmetrical about centers of said duty cycles of respective switches at the input of the resonant circuit. Thus, operation of the converter is substantially simplified by using only PWM, a wide range of input and output voltages can be achieved and the converter circuit can be configured for bi-directional power transfer.

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Blacksburg, VA, United States of America

Khai Doan The Ngo