Abstract: Apparatus and method for a polarity independent step-up converter capable of operating with ultra low input voltage. The step-up converter as disclosed herein receives an input source having a variable polarity and includes a first core circuit coupled to the input source and an output of the step-up converter and a second core circuit coupled to the input source and the output of the step-up converter. The first core circuit is configured to be active for a first input voltage polarity to output a first step-up voltage and the second core circuit is configured to be active for a second input voltage polarity to output a second step-up voltage.

Abstract: A tap changer for connection to a regulating winding of a rated regulation voltage is provided. The tap changer having a linear tap selector having at least one current collector and a linear arrangement of fixed contacts. Tap changer further includes a shielding structure arranged to shield the tap selector from an external electrical field. The shielding structure includes: a first shielding part arranged to be electrically connected to a current collector; and a second shielding part formed at least partly by the fixed contacts. The first and second shielding parts are separated so that the distance between the first and second shielding parts reaches or exceeds the rated regulating voltage insulation distance of the tap changer.

Abstract: A tunable coil antenna (2) is disclosed, in which the tunable coil antenna (2) comprises a first antenna terminal (12), and a series of two or more incomplete turns (4), each incomplete turn (4) comprising a first end (8) and a second end (10), the first end (8a) of the first incomplete turn (4a) being electrically connected to the first antenna terminal (12), the first end (8) of each subsequent incomplete turn (4) arranged to be electrically connected to the second end (10) of a preceding incomplete turn (4) in the series, the second end (10) of each incomplete turn (4) arranged to either be electrically connected to the first end (8) of a subsequent incomplete turn (4) in the series or to provide a second antenna terminal.

Abstract: A spiral inductor device is provided. The spiral inductor device comprises an insulating layer disposed on a substrate. A spiral conductive trace with multiple turns is disposed on the insulating layer, wherein the outermost turn and the innermost turn of the spiral conductive trace have a first end and a second end, respectively, and one of the first and second ends is connected to ground. A non-continuous spiral conductive trace with a single turn is disposed on the insulating layer, parallel and adjacent to the turn that belongs to the spiral conductive trace and is extended from the end of the spiral conductive trace without being connected to ground, wherein the non-continuous spiral conductive trace is connected to the ground.

Abstract: A multiphase inductor assembly includes an elongate conductor assembly including a plurality of bus bars that are arranged in parallel. A plurality of magnetic core material rings (e.g., ferrite or mu metal rings) surround the conductor assembly and are distributed along a length thereof. Terminals are electrically coupled to the bus bars and disposed between spaced apart ones of the magnetic core material rings. In some embodiments, the conductor assembly, in cross-section, includes respective ones of the bus bars disposed in respective quadrants. For example, each of bus bars may have a quarter-cylinder shape and may be arranged such that the conductor assembly has a circular cross-section. In other embodiments, each of the bus bars may have a polygonal cross-section, e.g., may be formed from standard rectangular bar stock.

Abstract: Apparatus for supplying energy to a load, comprises a power supply unit (102) e.g. a switched mode electronic transformer or electronic ballast having an input for receiving current at mains frequency and a means for stepping-up said mains frequency to a higher frequency e.g. 30-50 kHz and an output for delivering energy at the higher frequency. A two part connector (108) has a first core portion (106) that has a primary winding (104) connected to the output of the power supply unit and a mating second core portion (112) that has a secondary winding (110) for delivery of energy to a load (114), the core portions being of a high resistivity material, e.g. a ferrite having a resistivity of at least 104 ?cm. The apparatus may be used to power e.g. low voltage halogen or other incandescent lighting, fluorescent lighting, or an electric motor, a power supply for a computer, radio, television or like electronic device, a heater or the like.

Abstract: A monolithic high-Q inductor structure is formed with multiple metalization levels in a conventional integrated circuit technology in which inductor turns utilize these multiple levels to reduce the inductor resistance. Inductors with Q values above five can be integrated with this approach at radio and microwave frequencies.

Abstract: A voltage control system has a pair of clockwise and counterclockwise interleaved coils on a portion of a transformer core, the coils having multiple spaced turns providing sets of co-planar alternate electrical contact pairs extending linearly to form a tapping system for varying the output voltage of the transformer. A conductive electrical bridging member is movable in the linear direction of extension of the contacts and bridges a selected pair of contacts, one contact from each coil, to alter the effective number of electrical turns of the two coils between a minimum and maximum output voltage. An adjunctive feature is to provide both a contact lead to the bridging member and appropriate rectification at output ends of the pair of coils in order to produce a direct current output.

Abstract: Apparatus for producing induction currents in a pipe to heat the same comprising an axially extending collar adapted to removably surround the pipe, the collar including at least two arcuate frames hingedly connected in end to end circumferential relationship and having a pair of free ends adapted to be opened for placing the frames around the pipe, a plurality of electrically conducting wires carried upon the frames across the axial width thereof and extending circumferentially between the free ends, a connector assembly mounted at each free end, each connector assembly having a plurality of connectors, each connector of each assembly being connected to an end of a wire and being connected electrically to a connector of the other assembly when the frames are in closed position around the pipe, the wires on one axial half of the collar being connected to each other to form two interlaced bifilar windings; the wires at the other axial end of the collar being interconnected to form two interlaced bifilar windin

Abstract: The method of and apparatus for changing the inductance of a high power air core coil through the process of selectively shorting out predetermined numbers of turns. The apparatus comprises a conductive belt which is positioned interior the coil whereby the problems of corona discharge from the winding contents are substantially reduced. Since the shorting conductor is a thin film of conductive material attached to a tape, the mass is very low and vibration forces applied to the unit have much less effect in producing interruptions of contact.