Abstract: A differential type sensing unit which includes a winding core having a winding shaft is described. In one embodiment, a post extends from the winding shaft and is located intermediate first and second winding ends of the winding shaft. The post facilitates reversing the winding direction of a conductor wound on the winding shaft. The conductor is wound such that the sensing unit includes a first sensing coil and a second sensing coil formed in a series opposing configuration. The sensing unit may be integrated with a driving unit to include driving coils formed over the top of the sensing coils.

Abstract: An inductive structure for use in high frequency integrated circuits is provided. A conductive path forming the structure is arranged so extra conductive material is located at portions of the cross-section of the conductive path where current tends to flow at high frequency.

Abstract: A distribution transformer has a wound magnetic core (50) of overall circular shape and rectangular cross-section with between two and four overall rectangular shape electric coils (20,30) extending through the core window. The coils (20,30) are pre-formed and assembled so that their parts (20A,30A) which meet form a circular section solid cylinder. A mandrel (40) is then located around this cylinder (20A,30A) and continuous non-amorphous steel strip is wound thereon to form an unannealed, uncut wound magnetic core of axial length in the range 250 mm to 1 m. In a modification, amorphous steel strip is first wound on to another mandrel, annealed, and then transferred from the other mandrel on to the mandrel around the coils.

Abstract: A connecting member is fixedly mounted in a predetermined location so as to penetrate a closed space formed with a ferrite core, and an end of a first lead wire is inserted and connected with an engagement part formed at one end part of the connecting member, and an end of a second lead wire is inserted and connected with an engagement part formed at the other end part of the connecting member, thereby, the trigger winding is formed.

Abstract: A current controlled variable inductor comprises a magnetically saturable E" core having outer limbs each joined to a center limb by connecting limbs. A staggered series of flux bridges and air gaps are formed into alternating sides of the outer limbs. A bias winding on the center limb magnetically couples a direct current into the core to vary the inductance of a signal winding on the outer limbs. A secondary winding magnetically couples an output voltage from the core for application of the inductor as a tunable transformer.

Abstract: An improved phase angle regulator with about 70% of the total impedance in the series unit and 30% in the excitor unit. In order to balance the physical size of both units, the excitor unit includes an interleaved winding arrangement. On large phase angle regulators, the higher impedance in the series unit allows for the use of a three-leg core design, and the low impedance interleaved excitor unit can also be designed on a three-leg core. The higher impedance series unit reduces the zero sequence current in the unit by about 40% during a single line to ground fault. Also the interleaved winding arrangement in the excitor unit improves its short circuit withstand capability.

Abstract: A winding configuration for a transformer equipped with a load tap changer which maintains an impedance balance when the transformer is connected in parallel with another transformer in the field. The winding configuration, from the core outward, consists of a first compensating winding, a low voltage (LV) winding, a load tap changer (LTC) winding, a high voltage (HV) winding, and a second compensating winding. If the impedance of the transformer has to be lowered to match the impedance of the existing unit in the field, the second compensating winding is coupled in series with the LV winding. If the impedance of the transformer has to be increased to match the impedance of the existing unit in the field, the first compensating winding is coupled in series with the LV winding.

Abstract: Two unequal impedance input port RF power combiner is used alone or as a component of a three equal input impedance input port RF power combiner with isolation between all ports. The combiner has a band pass of at least two octaves and the capacity to handle at least 5 kw. The combiner may be used in a transmission system and methods of isolation of the input ports by the resistive shunting of selected transformer windings are disclosed.

Abstract: A transformer having a core of soft magnetic material around which a first winding and a second winding are wound and a leakage inductance based on the magnetic coupling between these windings. The effective leakage reactance is minimized by adding a third transformer winding serially connected to a capacitor, the latter of which is varied to reduce the leakage reactance over a broad frequency range.

Abstract: A power transformer for cycloconverters comprises an iron core having three legs, nine positive group windings, nine negative group windings, and nine power supply windings. Three of the positive group windings, three of the negative group windings and three of the power supply windings are wound on each leg of the iron core. In application to the cycloconverters, three positive and negative group windings are allotted to each of three converters of the cycloconverter so that the three-phase AC voltages are applied to the three converters respectively. The three power supply windings are allotted to each pair of positive and negative group windings so that a winding circuit impedance becomes equal between the positive and negative group windings. These windings are arranged into a single transformer in which the windings are magnetically connected together by one three-leg core.

Abstract: A magnetic core (2) is formed so as to be vertically thin and segmentable into an upper segment (3) and a lower segment (4). An inner portion (2a) and two outer portions (2b), (2b) of the magnetic core (2) are interconnected so as to form a closed magnetic circuit. A substrate (9) is inserted between the two outer portions (2b), (2b), while the inner portion (2a) is inserted into a through hole (10) of the substrate (9). A scroll pattern coil (11) is formed on each of front surface (9a) and rear surface (9b) of the substrate (9) outside the through hole (10). Further, a bobbinless winding coil (13) is inserted into an annular space between the inner portion (2a) and the through hole (10).

Abstract: A transformer (202) has a bobbin (2) which has an inner portion (104) supporting an inner electrical winding (140) and having a magnetic core recess. The inner portion is located within an outer portion (4) supporting an outer electrical winding (40). The inner portion further has an end with a termination connected to the inner winding, an annular recess (126) in which the inner winding is situated, and a channel (132) communicating between the termination end of the inner portion and a remote end of the annular recess. The channel is positioned radially inwardly of the first annular recess and accommodates a portion of the inner winding. By providing the channel radially inwardly of the annular recess, winding wire can extend between the termination end of the inner portion and the remote end of the annular recess across the annular recess without significantly increasing the size of the inner portion and without increasing the gap between the inner and outer portions.

Abstract: A motor control system includes a single, multicompartment enclosure mounted on a skid. The enclosure contains a transformer circuit and a motor controller circuit interconnected so that only external connections to a power source and a load are needed. When the circuits are energized, access to high voltage motor control components and to field replaceable fuses and output selection switches is prevented by a double interlocking mechanism which operates in conjunction with energizing and deenergizing the transformer. The transformer of the transformer circuit includes a tertiary winding disposed radially between a primary winding and a secondary winding. The winding filters electrostatically coupled transients. A conventional electrostatic shield is also used so that the transformer is doubly shielded to electrostatic transients. The tertiary winding is connected to one or more capacitors to filter magnetically coupled transients.

Abstract: A hybrid high voltage transformer includes three nesting cylindrical coil forms. The inner coil form supports a primary winding and the two outer coil forms support secondary windings that substantially overlie the primary winding. Each of the secondary winding coil forms includes a plurality of circumferential walls forming individual compartments for supporting a multilayered group of coil turns in a substantially uniform pattern over the coil form. The outer coil form includes an upraised central portion to permit tapping of the secondary winding thereon for a DC focus voltage at AC ground. The coil forms include protrusions for supporting connection posts for making electrical connections and supporting electrical components. The two secondary windings are wound in opposite directions.

Abstract: A core for an integrated magnetic power converter includes a continuous magnetic structure having first and second legs and a magnetic flux conducting path therebetween. A primary winding is disposed on the first leg. A first secondary winding is disposed on the first leg. A second secondary winding is disposed on the second leg. The first leg has a cross-sectional area which is greater than the cross-sectional area of the second leg.

Abstract: At least two three-phase transformer arrangements include a plurality of primary windings connected in a wye configuration and at least two converter arrangements, each converter arrangement comprising a plurality of secondary windings connected in a double-wye configuration. A separate rectifier is connected in series with each secondary winding of each converter arrangement.

Abstract: A radio frequency choke for a cable or CATV system is designed for blocking signals from 5 to 1000 MHz and passing 60 Hz AC power. The RF choke has a wire coil that is wound upon a coil form of a predetermined cross section, the coil being formed of a number of successive spaced windings on the form, with each winding being joined to the next by an air coil of at least one turn, formed off the loop. The various successive windings should have different numbers of turns. Forming the air coils tends to tighten the windings onto the form, so that a fixative coating or adhesive can be eliminated or omitted.

Abstract: In one form of the multiple voltage ballast system described herein, each of the primary coils has different wire sizes with the largest diameter wire being utilized in the 120 V primary coil. In another form of the invention, a pair of 120 V primary coils are connected in series with a 37 V primary coil so that the ballast may function as a 277 V ballast. The primary coils are also electrically connected so that the ballast may be used as a 120 V ballast.

Abstract: Novel switched mode boost-buck integrated magnetic power converters are disclosed featuring two winding bobbins, a new boost section with enhanced gain, means for operating the converter in a continuous mode of energy storage under minimum output loading conditions while providing adequate time for removing the magnetization energy of the transformer part of the integrated magnetics, and other new and different converter topologies.

Abstract: An apparatus for producing a very high DC potential output from an AC input. Multiple secondary circuits, each comprised of an individual coil wound about a separate magnetic core, are positioned within the magnetic field of a single primary coil. The output of each secondary circuit is rectified. The output of all secondary circuits is combined in series to provide the high DC potential. The seconary cores are supplied in parallel from the magnetic flux of the primary coil. The primary core and coil form an essentially cylindrical shell, with the secondary cores and coils located within the cylinder interior.

Abstract: A method of manufacturing a transformer with coaxial coils. A coil bobbin (1) is provided with a first flange (3) and a second flange (5) between which a winding space is informed in which a first coil (9) is wound. Around the first coil an electrically insulated foil (13) is fitted, on which one or more second coils (15, 17) are wound. An essentially U-shaped spacer (23) made of an electrically insulating material is placed, before the winding of the second coil (15, 17), around the insulating foil (13) such that its members (27) extend axially into the winding space. Each of the members (27) is provided near the first flange (3) with a first radial projection (29) and near the second flange (5) with a second radial projection (31). These projections define a minimum possible distance between the second coil (15, 17) and the first and second flanges.

Abstract: Novel switched mode boost-buck integrated magnetic power converters are disclosed featuring unique core shapes, two winding bobbins, a core which provides electro-magnetic shielding, and cores which are readily adapted to accept a wide range of converter topologies.

Abstract: The invention provides an electric transformer for microwave ovens including a conventional magnetic circuit with three columns, and electric circuits insulated by carcases and covers made from an insulating material. The secondary carcase forms a particular housing for the secondary heating winding so that the secondary high voltage winding and the secondary heating winding are partially superimposed. Thus an excellent electric insulation is provided without loss of space.

Abstract: A combined transformer and motor having a continuously energized primary winding producing a continuous output voltage from a transformer winding and a selectively enabled motor shaft rotational output which is selectively actuated by powering a further primary winding, and further having a reduced cross section area in the flux conducting structure of the combined transformer and motor for improving the regulation of the output voltage.

Abstract: A multifilar transformer apparatus and winding method where first and second windings are bifilar wound around a core for NA turns, the first, second, third, and fourth windings are quadfilar wound around the core for NB turns, and the first and second windings are again bifilar wound around the core for NC turns. Winding symmetry is preserved and a turns ration of (NA+NB+NC):2NB is achieved.

Abstract: A transformer for use in a power converter includes first and second primary windings tightly coupled to a first secondary winding, and third and fourth primary windings tightly coupled to a second secondary winding. Of importance, the first and second primary windings are only loosely coupled to the third and fourth primary windings. In one embodiment of the invention, the transformer includes a plurality of legs. The first and second primary windings and the first secondry winding are wound around one half of one of the legs but not a secnd half of the one leg. The third and fourth primary windings and the second secondary winding are wound around the second half of the one leg but not the first half. In another embodiment of the invention, the transformer includes a U core. The first and second primary windings and the first secondary winding are wound around a first leg of the U core while the third and fourth primary windings and the second secondary winding are wound around a second leg of the U core.

Abstract: A substantial reduction in the common-mode noise generated by a switching-mode power converter is achieved by incorporating a multifilar-wound transformer into the converter in such manner that the inter-winding capacitances cause a cancellation of common-mode, noise components at the converter output.

Abstract: A high voltage transformer incorporates a bobbin on which the primary winding is wound. The transformer auxiliary coils are wound directly over the primary winding with no intermediate layers of insulation. The wire turns of the auxiliary coils are evenly distributed over the full traverse of the primary winding to improve magnetic coupling and simplify tuning of the transformer.

Abstract: A flyback transformer wherein the tertiary coil is wound on an auxiliary bobbin provided separately, insertedly on the low tension coil bobbin for the primary coil, thereby to render to insulate completely the tertiary coil from the primary coil.

Abstract: An electric resonator includes first and second pluralities of conductors which are disposed in side-by-side relationship to form a first layer of alternating first and second conductors. Additional layers of alternating first and second conductors are disposed atop the first layer such that each conductor of one of the pluralities is horizontally and/or vertically adjacent to conductors of the other plurality. The resulting resonator reduces undesirable capacitance between various conductors thereby increasing the quality factor, or Q, of the resonator.

Abstract: A transformer assembly suitable for use in very high frequency (VHF) switching power supplies that maintains a low leakage inductance between critical transformer windings while complying with the physical and electrical requirements imposed by standards for primary to secondary isolation. The transformer includes a telescopic bobbin assembly with an inner and an outer section that telescope together to form an interior clearance space or chamber between the two sections. The interior chamber has a narrow conduit exiting to the exterior of the bobbin assembly. Described are two embodiments for a transformer used in a forward-averaging type converter and a third embodiment for a transformer used in a frequency modulated converter.

Abstract: A low frequency transformer for an audio system has a core, a primary winding, a secondary winding, insulation between the primary and secondary windings, a tertiary winding, and insulation between the secondary and tertiary windings. One end of the tertiary winding is embedded in the insulation between the secondary and tertiary windings, and the other end is grounded. With a tertiary winding arranged and connected in this fashion, the effects of external interference signals are substantially eliminated, and the output of the transformer is improved, i.e., it has less waveshape and frequency distortion. Preferably, the primary and tertiary windings are wound around the core in the same direction while the secondary winding is wound around the core in the opposite direction.

Abstract: A converter transformer for an AC-DC converter is assembled by connecting three transformer units at an installment site. In the respective transformer units, first, second and third iron core legs are received in oil tanks. On the first and second core legs are mounted series-connected first and second primary windings, respectively. On the second and third legs are mounted first and second secondary windings respectively. Coupling windings connected in parallel are mounted on the respective legs. The primary windings and the secondary windings are electromagnetically coupled.

Abstract: Low, middle and high voltage windings are wound on a magnetic core in this order, the high voltage winding having a high voltage line terminal at its center and neutral terminals at both ends. Two middle voltage partial windings are coaxially wound on the outside of the high voltage winding at upper and lower positions separated by a necessary distance for insulation. One end of each of the middle voltage partial windings are connected to the neutral point of the middle voltage winding, and the other ends thereof are each connected to the respective tap windings of two tap changers. Thus, the middle voltage partial windings and the tap changers constitute a parallel circuit in which a circulating current flows thereby to induce magnetic flux in each of the middle voltage partial windings and tap windings. The middle voltage partial windings and tap windings are so wound that the magnetic coupling therebetween through the induced magnetic flux can be reduced.

Abstract: An electrical coupling arrangement suitable for connecting protective relays to the primary current transducers in an alternating current power transmission system, comprising three winding arrangements flux linked so that an a.c. input current applied to one winding arrangement provides an a.c. output voltage substantially free of d.c. transients at a second winding arrangement, the third winding arrangement including a resistance which is variable and whose value determines the phase relationship between the output voltage and the input current.