Saturable Reactor (e.g., Magnetic Amplifier) Patents (Class 363/91)
  • Patent number: 11923800
    Abstract: A system includes a generator control unit (GCU). The GCU includes a saturable reactor and a rectifier. Each of the saturable reactor and the rectifier has a separate input to receive AC power from a separate respective permanent magnet generator (PMG). A method includes supplying AC power from a first permanent magnet generator (PMG) of a generator to a saturable reactor of a generator control unit (GCU) that is operatively connected to control the generator. The method includes supplying AC power from a second PMG to a rectifier of the GCU, wherein the first PMG supplies a lower AC voltage to the saturable reactor than the second PMG supplies to the rectifier.
    Type: Grant
    Filed: May 6, 2022
    Date of Patent: March 5, 2024
    Assignee: Hamilton Sundstrand Corporation
    Inventors: Dhaval S. Patel, Adrian E. Vandergrift, Sunil S. Patel
  • Patent number: 11736002
    Abstract: The present invention relates to an adaptive soft start and soft stop device for a converter, and more particularly, provides an adaptive soft start and soft stop device for a converter which controls a final output voltage to be increased or decreased with a predetermined gradient by increasing a duty at a predetermined rate or increases a frequency during a start period using an input voltage Vin and an output voltage Vo and decreasing the duty at a predetermined rate or decreases a frequency during a stop period.
    Type: Grant
    Filed: June 28, 2021
    Date of Patent: August 22, 2023
    Assignee: Power LSI Co. ltd
    Inventors: Won Tae Lee, Won Ji Lee, Chang Sik Shin, Chuen Sik Jung, Gyu Won Lee
  • Patent number: 11658518
    Abstract: A wireless power circuit operable in transceiver mode and in Q-factor measurement mode includes a bridge rectifier having first and second inputs coupled to first and second terminals of a coil, and an output coupled to a rectified node. An excitation circuit coupled to the first terminal, in Q-factor measurement mode, drives the coil with a pulsed signal. A protection circuit couples the first terminal to a first node when in Q-factor measurement mode and decouples the first terminal when in transceiver mode. A controller causes the bridge rectifier to short the first and second terminals to ground during Q-factor measurement mode. A sensing circuit amplifies voltage at the first node to produce an output voltage, and in response to the voltage at the first node rising to cross a rising threshold voltage, digitizes the output voltage. The digitized output voltage is used in calculating a Q-factor of the coil.
    Type: Grant
    Filed: August 23, 2021
    Date of Patent: May 23, 2023
    Assignee: STMicroelectronics Asia Pacific Pte Ltd
    Inventors: Baranidharan Karuppusamy, Thet Mon Sann, Kien Beng Tan, Supriya Raveendra Hegde, Huiqiao He, Teerasak Lee
  • Patent number: 11502548
    Abstract: A control system is provided that includes a power transmitting coil for wirelessly transmitting power supplied from a power source, a power receiving coil for wirelessly receiving power by electromagnetic coupling between the power transmitting coil and the power receiving coil, a driving circuit configured to drive a load portion using the power received via the power receiving coil, a transmitting coupler for wirelessly transmitting a transmission signal for controlling driving of the load portion, a receiving coupler for wirelessly receiving the transmission signal by electromagnetic coupling between the transmitting coupler and the receiving coupler, and a generation circuit configured to generate a driving signal for controlling the driving circuit from the transmission signal received via the receiving coupler.
    Type: Grant
    Filed: May 18, 2020
    Date of Patent: November 15, 2022
    Assignee: Canon Kabushiki Kaisha
    Inventor: Takeshi Ide
  • Patent number: 11264887
    Abstract: A multi-pulse transformer for an industrial machine, the multi-pulse transformer including a primary winding and a plurality of secondary windings. The primary winding coupled to a power source, the power source operable to generate a primary voltage. The secondary windings are coupled to one or more converters, each of the secondary windings are phase shifted with respect to the primary winding. The converters are operable to provide a secondary voltage to at least one component of the industrial machine. Wherein the multi-pulse transformer converts the primary voltage to the secondary voltage and attenuates harmonic distortions caused by the converters and the component of the industrial machine. Additionally, the secondary voltage is at a voltage less than the primary voltage.
    Type: Grant
    Filed: April 28, 2016
    Date of Patent: March 1, 2022
    Assignee: JOY GLOBAL SURFACE MINING INC
    Inventors: William A. Dorsett, David T. Huber, Jason L. Esser
  • Patent number: 10746806
    Abstract: A driver circuit arrangement for driving a transistor bridge, which includes at least a first half-bridge composed of a low-side transistor and a high-side transistor, is described herein. In accordance with one example of the description, the circuit includes a current source and a detection circuit. The current source is operably coupled to the high-side transistor of the first half-bridge and configured to supply a test current to the first half bridge. The detection circuit is configured to compare a voltage sense signal, which represents the voltage across the high-side transistor of the first half-bridge, with at least one first threshold to detect, dependent on the result of this comparison, whether a short-circuit is present in the first half-bridge.
    Type: Grant
    Filed: March 22, 2016
    Date of Patent: August 18, 2020
    Assignee: Infineon Technologies AG
    Inventors: Alexander Heinz, Matthias Bogus
  • Patent number: 10355615
    Abstract: A rectifier circuit is configured to receive first and second alternate current (AC) signals that have opposite phases. The rectifier circuit includes a first half-wave rectifier circuit that includes a first metal-oxide-semiconductor (MOS) transistor and a second MOS transistor connected in series, and performs half-wave rectification on the first AC signal to generate a first direct current (DC) signal, a second half-wave rectifier circuit that includes a third MOS transistor and a fourth MOS transistor connected in series, and performs the half-wave rectification on the second AC signal to generate a second DC signal, the first DC signal and the second DC signal being outputted by the rectifier circuit to a load, and a body potential setting circuit configured to set a body potential of each of the first MOS transistor, the second MOS transistor, the third MOS transistor, and the fourth MOS transistor.
    Type: Grant
    Filed: March 28, 2018
    Date of Patent: July 16, 2019
    Assignee: LAPIS Semiconductor Co., Ltd.
    Inventor: Takashi Nakamura
  • Patent number: 10298218
    Abstract: The invention relates to a method and a device for controlling an electrical or electronic switching element that can be activated by an electrical signal, wherein a PWM signal can be produced by a PWM module for controlling the switching element and which can be modulated as a function of the supply voltage and/or of an ambient temperature on the electromechanical or electronic switch.
    Type: Grant
    Filed: November 26, 2016
    Date of Patent: May 21, 2019
    Assignee: PHOENIX CONTACT GMBH & CO. KG
    Inventors: Lutz Heuer, Stephan Hansmeier, Bernd Schulz, Dirk Plewka
  • Patent number: 9257895
    Abstract: The invention comprises a high frequency inductor filter apparatus coupled with an inverter yielding high frequency harmonics and/or non-sixty Hertz output. For example, an inductor/converter apparatus is provided that uses a silicon carbide transistor to output power having a carrier frequency, modulated by a fundamental frequency, and a set of harmonic frequencies. A filter, comprising an inductor having a distributed gap core material and optional magnet wires, receives power output from the inverter/converter and processes the power by passing the fundamental frequency while reducing amplitude of the harmonic frequencies.
    Type: Grant
    Filed: July 30, 2013
    Date of Patent: February 9, 2016
    Inventor: Grant A. MacLennan
  • Patent number: 9075425
    Abstract: An adjustable output power supply with a data communications connector that at least partially complies with physical specifications of a defined data interface standard connector, such as a USB connector. The data communications connector has a number of data contacts and power contacts coupled to and providing output electrical power from a programmable power supply. A controller receives an indication of a detection of a feature of a mating connector coupled to the data communications connector, determines, based on receiving the detection, at least one resistance value between a data contact and at least one power contact, and adjusts an output voltage of the programmable power supply based on the at least one resistance value.
    Type: Grant
    Filed: April 19, 2013
    Date of Patent: July 7, 2015
    Assignee: BlackBerry Limited
    Inventors: Douglas James Arthur Burrell, Jason Tyler Griffin, Todd Andrew Wood
  • Patent number: 7499300
    Abstract: A synchronous rectification and voltage stabilization circuit includes a saturable inductance coil (L1), a synchronous rectifier switch (33), a driving coil (L2) for turning on the synchronous rectifier switch, a discharging coil (L3) which co-operates with a controllable switching component (Q1) to turn off the synchronous rectifier switch, a filter circuit (40) and a voltage stabilization circuit (50). The saturable inductance coil, the synchronous rectifier switch and the filter circuit are connected in serial between an input terminal (10) and an output terminal (20). The saturable inductance coil is coiled together with the driving coil and the discharging coil on one core. The voltage stabilization circuit is connected between the output terminal and the saturable inductance coil, and is used for regulating a regulable saturation point of the saturable inductance coil according to an output voltage of the output terminal and a target value of the output voltage.
    Type: Grant
    Filed: August 10, 2006
    Date of Patent: March 3, 2009
    Assignee: Hon Hai Precision Industry Co., Ltd.
    Inventors: Shin-Hong Chung, Kuan-Hong Hsieh
  • Patent number: 7352136
    Abstract: A DC-DC converter reduces a surge voltage developed across a switching element (30) in making the voltage conversion with the use of a transformer (20) inherently having considerable leakage. A snubber circuit is included to absorb the surge energy and transferring it to a load, or output end of the converter, reducing the surge voltage across the switching element (30). A snubber capacitor (51) is provided to absorb the surge energy developed by the transformer (20) when the switching element (30) is off. Thus absorbed energy is collected in a storage capacitor (53) through a reactor (54) while the switching element (30) is on and off, and is then transferred from the storage capacitor (53) to the load, i.e., the output side of the converter, leaving only a minimum voltage being applied across the switching element (30).
    Type: Grant
    Filed: March 2, 2004
    Date of Patent: April 1, 2008
    Assignee: Matsushita Electric Works, Ltd.
    Inventor: Takashi Kambara
  • Patent number: 7139179
    Abstract: A switched mode power converter includes a transformer having a primary winding, a secondary winding, and a bias winding. A primary side power switch is coupled to the primary winding and is adapted to periodically apply an input voltage to the primary winding. An output filter is operatively coupled to the secondary winding to provide an output voltage and output current. A forward synchronous rectification device is operatively coupled in series between the secondary winding and the output filter. A free-wheeling synchronous rectification device is operatively coupled in shunt with the secondary winding and the output filter. A control circuit is coupled to the bias winding and the forward and free-wheeling synchronous rectification devices.
    Type: Grant
    Filed: April 29, 2005
    Date of Patent: November 21, 2006
    Assignee: Semtech Corporation
    Inventor: Lei Hua
  • Patent number: 7133298
    Abstract: A switching regulator and method of fabricating a switching regulator is disclosed. In one embodiment a switching regulator comprises a transformer having a primary winding and a secondary winding, an inductor (L) connected to an input of the primary winding, and a capacitor (C) connected across the primary winding of the transformer. The inductor and capacitor form a L-C tank circuit. The switching regulator also includes a frequency source connected to the inductor, wherein the frequency source provides a switching frequency to the inductor that is substantially equal to a resonant frequency of the L-C tank circuit.
    Type: Grant
    Filed: October 25, 2004
    Date of Patent: November 7, 2006
    Assignee: Texas Instruments Incorporated
    Inventor: Paul Louis Schimel
  • Patent number: 6933710
    Abstract: Improved soft start techniques for control loops that regulate DC/DC converter circuits are provided. An improved soft start circuit provides a varying voltage at the output of an error amplifier in the control loop during the start-up phase of the DC/DC converter. The varying voltage generated by an improved soft start circuit is related to the amplitude of the saw-tooth ramp signal that controls the switching duty cycle. The varying voltage generated by an improved soft start circuit is also related to the switching frequency of the DC/DC converter. These features allow the duty cycle of the DC/DC converter to gradually increase from zero during power-on. An effective soft start function is provided for DC/DC converters that have a variable switching frequency or a variable saw-tooth ramp signal.
    Type: Grant
    Filed: February 18, 2003
    Date of Patent: August 23, 2005
    Assignee: Fairchild Semiconductor Corporation
    Inventor: Crown-Sen Shieh
  • Patent number: 6845021
    Abstract: The present invention provides a multi-output DC-DC converter which supplies an input direct voltage to a series circuit consisting of a primary winding (3a) of a transformer (3) and a switching circuit (2) to obtain first and second output direct voltages from a secondary winding (3b) of the transformer (3) via first and second rectifying circuits, wherein a switching signal of the switching circuit (2) is controlled corresponding to the first output direct voltage so that the first output direct voltage is caused to be constant, and a variable reactor (10) is inserted into the second rectifying circuit. Thus, loss of power can be reduced in a simplified configuration.
    Type: Grant
    Filed: December 10, 2001
    Date of Patent: January 18, 2005
    Assignee: Sony Corporation
    Inventors: Hiroki Kanehira, Hiroshi Akama
  • Patent number: 6785151
    Abstract: A circuit and method provides a regulated dc—dc power conversion. Active switches, saturable core inductors, and a diode are used in a quasi-synchronous circuit. During a part of the cycle (the “blocking interval”) free-wheeling current is routed through free-wheeling diode while a saturable core inductor is in a high-impedance, blocking state. During other parts of the cycle an ac inverter voltage is rectified by active switching devices, preferably field effect transistors (FETs). The circuit provides regulated, low voltage outputs with low conversion losses.
    Type: Grant
    Filed: March 14, 2003
    Date of Patent: August 31, 2004
    Assignee: Condor D.C. Power Supplies, Inc.
    Inventors: Thomas M. Ingman, Charles E. Mullett
  • Patent number: 6614131
    Abstract: A switched mode power supply having a first circuit provided with a primary winding of a transformer to which a pulse voltage is applied, a second circuit having a secondary winding of the transformer, a reactor provided with a magnetic core and which has a terminal connected to a terminal of the secondary winding, at least one filter provided with input and output terminals and a first diode connected in parallel to the input terminals of the filter is shown. The other terminal of the reactor is connected to a terminal of the first diode. The power supply includes a second diode that has a first terminal connected to the other terminal of the first diode and a second terminal connected to the other terminal of the secondary winding and a control circuit coupled to an output terminal of the filter and to the other terminal of the secondary winding. The control circuit generates a current able to reset the magnetic core of the reactor.
    Type: Grant
    Filed: January 22, 2002
    Date of Patent: September 2, 2003
    Assignee: STMicroelectronics S.r.l.
    Inventors: Franco Lentini, Fabrizio Librizzi
  • Patent number: 6504737
    Abstract: A magnetic core for use in a saturable reactor made of an Fe-based soft-magnetic alloy comprising as essential alloying elements Fe, Cu and M, wherein M is at least one element selected from the group consisting of Nb, W, Ta, Zr, Hf, Ti and Mo, and having an alloy structure at least 50% in area ratio of which being fine crystalline particles having an average particle size of 100 nm or less. The magnetic core has control magnetizing properties of a residual operating magnetic flux density &Dgr;Bb of 0.12 T or less, a total control operating magnetic flux density &Dgr;Br of 2.0 T or more, and a total control gain Gr of 0.10-0.20 T/(A/m) calculated by the equation: Gr=0.8×(&Dgr;Br−&Dgr;Bb)/Hr, wherein Hr is a total control magnetizing force defined as a control magnetizing force corresponding to 0.8×(&Dgr;Br−&Dgr;Bb)+&Dgr;Bb.
    Type: Grant
    Filed: June 8, 2001
    Date of Patent: January 7, 2003
    Assignee: Hitachi Metals, Ltd.
    Inventors: Shin Nakajima, Hirohiko Miki, Sadami Kubota, Mutsuhito Sakaguchi
  • Patent number: 6501666
    Abstract: This invention provides a method and apparatus for magnetic amplifier to reduce the minimum load requirement of power supply. The apparatus comprises a voltage-dropper and a current-limiter. Through the voltage-dropper and the current-limiter, the master output of the power supply is coupled to the output of magnetic amplifier. The differential voltage of the master output and the magnetic amplifier output decide the voltage of the voltage-dropper. The current-limiter limits the current flows from the master output to magnetic amplifier output. If the master output is no load and the magnetic amplifier is full load condition, a start-up current will flow from the master output to the output of magnetic amplifier via the voltage-dropper and the current-limiter. In the mean time, the start-up current will widen the pulse width of the PWM signal until the current-limiter limits the current. The maximum current of the current-limiter is assigned to maintain the minimum pulse width of the PWM signal.
    Type: Grant
    Filed: August 15, 2001
    Date of Patent: December 31, 2002
    Assignee: System General Corp.
    Inventor: Ta-yung Yang
  • Patent number: 6490178
    Abstract: In a switching power circuit, one end of a primary winding of a transformer having a plurality of windings is connected to a voltage source, and the other end is connected to a return side of the voltage source through a first switching device. At least one of secondary windings of the transformer is connected to a forward-type rectifier circuit, which is comprised of a rectifier diode, a flywheel diode, a choke coil, and a smoothing condenser, through a MAGAMP. A second switching device is connected in parallel with the flywheel diode, and the second switching device is turned on/off according to an output of the secondary winding of the transformer or according to a signal acquired by inverting the secondary winding output.
    Type: Grant
    Filed: April 12, 2000
    Date of Patent: December 3, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventor: Atsushi Asayama
  • Patent number: 6449176
    Abstract: A switching power supply includes saturable reactors and an amplifier control circuit for reducing the differences of a reset amount of the magnetic flux due to the differences of the coercive forces of the saturable inductors. A reset time for the respective magnetic fluxes of the saturable inductors is made the same by controlling the respective products of the voltages applied to the saturable reactors by a time determined by the output voltage of the power supply.
    Type: Grant
    Filed: August 30, 2001
    Date of Patent: September 10, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Kiyotaka Kakuda
  • Publication number: 20020114175
    Abstract: A switched mode power supply having a first circuit provided with a primary winding of a transformer to which a pulse voltage is applied, a second circuit having a secondary winding of the transformer, a reactor provided with a magnetic core and which has a terminal connected to a terminal of the secondary winding, at least one filter provided with input and output terminals and a first diode connected in parallel to the input terminals of the filter is shown. The other terminal of the reactor is connected to a terminal of the first diode. The power supply includes a second diode that has a first terminal connected to the other terminal of the first diode and a second terminal connected to the other terminal of the secondary winding and a control circuit coupled to an output terminal of the filter and to the other terminal of the secondary winding. The control circuit generates a current able to reset the magnetic core of the reactor.
    Type: Application
    Filed: January 22, 2002
    Publication date: August 22, 2002
    Applicant: STMicroelectronics S.r.l.
    Inventors: Franco Lentini, Fabrizio Librizzi
  • Patent number: 6330171
    Abstract: The invention relates to a control circuit, in particular for a load in an automotive vehicle, comprising a chopping circuit, at least one LC filter (F1) means (20) opposing the saturation of the inductor, (L1) of this LC circuit, wherein these latter means (20) are provided so as to prebias the inductor in a chosen direction.
    Type: Grant
    Filed: December 22, 2000
    Date of Patent: December 11, 2001
    Assignee: Valeo Electronique
    Inventor: Ciprian Musat
  • Patent number: 6301139
    Abstract: A power converter has a self-driven synchronous rectification circuit that can operate efficiently with a non-optimal reset secondary voltage waveform that remains at a zero voltage level during a portion of the switching cycle. The power converter circuit includes a transformer having a primary winding and a secondary winding, in which primary winding is supplied with a non-optimal reset waveform that remains at a zero voltage level for a portion of a power cycle thereof. A first synchronous rectifier is connected in series with the first end of the secondary winding and is controlled by a voltage at the second end of the secondary winding. A second synchronous rectifier is connected in series with the second end of the secondary winding, and is further connected to an output terminal of the power converter circuit through a storage choke. A saturable reactor is connected in series between the first synchronous rectifier and the first end of the secondary winding.
    Type: Grant
    Filed: January 19, 2001
    Date of Patent: October 9, 2001
    Assignee: Power-One, Inc.
    Inventor: Amrit P. Patel
  • Patent number: 6246209
    Abstract: The present invention relates to a control of an AC motor, and in particular to a control device for an AC motor which can prevent an overvoltage from being applied to the motor, and minimize voltage consumption of a reactor itself during the starting and accelerating operation of the motor, by restricting a sharp increase of a motor line voltage resulting from a high-speed switching of an inverter during a high-speed operation of the motor, and a voltage reflection phenomenon of input terminals of the motor generated due to non-matching of a characteristic impedance between a power line and the motor, by inserting the reactor having a bar shaped core between the inverter and the motor.
    Type: Grant
    Filed: October 7, 1999
    Date of Patent: June 12, 2001
    Assignee: LG Industrial Systems Co., Ltd.
    Inventor: Han Jong Kim
  • Patent number: 6181116
    Abstract: A power regulator is provided which employs a resonant circuit and permits regulation between a certain maximum value and zero. A series resonant circuit is adjusted to regulate power by adjusting the correspondence between the resonance frequency and the frequency of the voltage source such as an AC source delivering a sine wave or a square wave. Further, the output voltage is regulated to be lower than the voltage of the AC source when output current is zero. A capacitance is connected in parallel with the output of the power regulator to form a second resonant circuit with the inductance of the series resonant circuit. A method of power regulation is also contemplated.
    Type: Grant
    Filed: May 22, 1998
    Date of Patent: January 30, 2001
    Assignee: NMB U.S.A. Inc.
    Inventor: Arian M. Jansen
  • Patent number: 6150821
    Abstract: A gradient magnetic field power supply includes an amplifier for supplying current to a gradient coil. Between input and output of the amplifier is connected a feedback circuit which feeds a portion of an output current at the output back to the input and has a built-in phase compensating circuit for compensating the phase of the feedback current. The frequency response of the phase compensating circuit is made variable and adjusted to fit variations in the load impedance of the amplifier with time. This ensures optimum phase compensation.
    Type: Grant
    Filed: February 9, 2000
    Date of Patent: November 21, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kiyomi Mori, Shigehide Kuhara
  • Patent number: 6049180
    Abstract: A supply is disclosed that develops a high dc voltage that may be applied to the anode of a cathode ray tube (CRT) of a display system. The supply provides the high dc voltage without the need for any high voltage flyback transformers and without the need of any power transistors. In one embodiment, the circuit of the invention is interposed between a subsystem of a power source of a horizontal deflection system, and the anode of the CRT.
    Type: Grant
    Filed: January 8, 1998
    Date of Patent: April 11, 2000
    Inventors: Edward M. Mengel, Richard L. Kies, Jr.
  • Patent number: 5956238
    Abstract: The blocking time maintenance circuit is applied to a resonant-transition ZVS power converter having saturable core reactors to induce a current in the primary of the transformer which enables ZVS. The circuit includes a peak detector for producing a signal having a magnitude proportional to an input voltage. A biasing mechanism, comprising a current source, is provided in order reset the saturable core reactors in a controlled manner. A control mechanism is connected to the peak detector and the current source in order to generate a reset current, the magnitude of which is correlated to the input voltage. In this manner, the volt-time product of the saturable reactors is varied, thereby maintaining the blocking time relatively constant over a wide range of input voltages and ensuring that the output voltage does not fall out of regulation.
    Type: Grant
    Filed: June 24, 1998
    Date of Patent: September 21, 1999
    Assignee: Celestica North America Inc.
    Inventor: Ronnie A. Wunderlich
  • Patent number: 5838558
    Abstract: A full-bridge converter 10 is provided which performs soft switching based on pulse width modulated switching signals. The, converter 10 includes a primary side 12 and a secondary side 14 interconnected through a transformer 13. The primary side 12 includes a power source connected in parallel with leading and trailing legs 20 and 22, respectively. The leading leg 20 includes first and second switching transistors Q1 and Q2 connected in series, while the trailing leg 22 includes third and fourth switching transistors Q3 and Q4 connected in series. The switching transistors Q1-Q4 each include parasitic diodes D1-D4 and parasitic capacitances C1-C4. A control circuit 15 generates pulse width modulated (PWM) switching signals applied to gates G1-G4 of the transistors Q1-Q4. The control circuit 15 simultaneously turns on transistors Q1 and Q3 during a first energy transfer stage and simultaneously turns on transistors Q2 and Q4 during a second energy transfer stage.
    Type: Grant
    Filed: May 19, 1997
    Date of Patent: November 17, 1998
    Assignee: TRW Inc.
    Inventors: F. Dong Tan, Leonard Y. Inouye
  • Patent number: 5691891
    Abstract: A rectifier for a switching power supply or the like. The recitifier has a plurality of diodes coupled in parallel, each diode having in series therewith a saturable inductor and a node disposed between the diode and the inductor to form a diode/inductor pair. At least one resistor is connected between at least two of the nodes to assure nearly equal current flow in the diodes. Alternatively, a link winding on at least two of the inductors are coupled together to achieve current balancing.
    Type: Grant
    Filed: May 3, 1996
    Date of Patent: November 25, 1997
    Assignee: Lucent Technologies Inc.
    Inventors: Greg H. Fasullo, Mark Elliott Jacobs, Kenneth John Timm
  • Patent number: 5612862
    Abstract: Magnetic amplifier post regulator (54) includes magnetic amplifier (42) that has a main magnetic amplifier winding, reset transistor (76), error amplifier (58), and auxiliary magnetic amplifier winding (220). Magnetic amplifier (42) controllably blocks a portion of the input voltage N.sub.s /N.sub.p V.sub.IN from winding (30) of transformer (18) in response to a controlled resetting condition and produces therefrom a magnetic amplifier output voltage (v.sub.2). Auxiliary output circuit (14) uses the magnetic amplifier (42) output voltage (v.sub.2) to produce the desired auxiliary output voltage (V.sub.OS). Reset transistor (76) controls reset current to magnetic amplifier (42) in response to an error signal from error amplifier (58). Error amplifier (58) compares auxiliary output voltage (V.sub.OS) to predetermined reference voltage (66) and generates the error signal from the comparison. Auxiliary magnetic amplifier winding (220) has a predetermined number of turns (N.sub.
    Type: Grant
    Filed: May 6, 1994
    Date of Patent: March 18, 1997
    Assignee: Alcatel Network Systems, Inc.
    Inventors: C. Lee Marusik, Edward Johnson
  • Patent number: 5592367
    Abstract: The apparatus for non-contacting feeding of a high frequency power according to the present invention comprises a double voltage full-wave rectifier circuit which converts an AC input into a DC output, Royer oscillation circuit consisting of FETs and which receives the DC output from the voltage double full-wave rectifier circuit and provides a high frequency oscillation, the gate windings ofhe FETs being the second winding of a saturable circuit, a starting gate bias stabilization circuit for the Royer oscillation circuit, and a main transformer which delivers a high frequency power produced in the Royer oscillation circuit, through the primary winding of the oscillation-use saturable transformer.
    Type: Grant
    Filed: October 6, 1994
    Date of Patent: January 7, 1997
    Assignee: Nippon Electric Industry Co., Ltd.
    Inventors: Katsunori Sugimori, Hiroshi Sakamoto
  • Patent number: 5539300
    Abstract: A power supply for an electronic device such as the control circuitry of a thermostat. The power supply has a current transformer with a primary winding in series with the power line that is connected to the heating source, and a secondary winding coupled to the primary winding through a saturable magnetic core. A thyristor connected across the output terminals of the secondary winding establishes a momentary short-circuit condition when the voltage developed across the secondary winding exceeds a preset level in order to prevent the magnet core of the transformer from saturating.
    Type: Grant
    Filed: August 1, 1994
    Date of Patent: July 23, 1996
    Inventor: Serge Mathieu
  • Patent number: 5521810
    Abstract: A rectifying saturable reactor generates a magnetic force in a magnetic iron core in response to a current that flows through an electronic circuit. The saturable reactor makes use of saturable magnetic flux in view of a hysteresis loop of a magnetic material for rectification and selects the saturated magnetic flux to be greater than an integrated value of a voltage applied to the rectifier in the rectifying circuit. In order to improve a rectifying performance, a no cut and one turn structure or an equivalent is introduced into a magnetic core for providing a hysteresis loop that varies as much as possible in magnetic induction.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: May 28, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Sataro Yamaguchi, Hiroyuki Sasao, Hiroshi Hasegawa, Kazuo Ikeda
  • Patent number: 5521808
    Abstract: Start-up control circuit (152) regulates the output voltage (V.sub.OS) of a power supply circuit (150). Magnetic amplifier control circuit (54) includes magnetic amplifier (42) and error detection circuitry (58, 68, and 70). Start-up control circuit (152) includes sensing circuitry (76 and 184) for generating sensing signals in response to voltage levels (V.sub.CC and V.sub.EE) in error detection circuitry (58, 68, and 70). Sensing signals indicate whether error detection circuitry (58, 68, and 70) voltage levels are sufficient to drive magnetic amplifier control circuit (54). Reset circuitry (190 and 192, and 194) associates with the sensing circuitry (76 and 184) for initially resetting magnetic amplifier (42) to prohibit output voltage (V.sub.OS) from power supply circuit (150) when the sensing signals indicate that voltage levels are insufficient for error detection circuitry to drive magnetic amplifier control circuit (54).
    Type: Grant
    Filed: May 6, 1994
    Date of Patent: May 28, 1996
    Assignee: Alcatel Network Systems, Inc.
    Inventors: C. Lee Marusik, Edward Johnson
  • Patent number: 5335163
    Abstract: A magnetic circuit with several magnetic components integrated on one or more common magnet cores is utilized in a current supply circuit known per se. The circuit comprises a transformer, the secondary winding ends of which are connected to uniform electrodes of a pair of rectifier diodes, the second electrodes of which are connected to one output terminal of the power supply circuit. Additionally, it includes two reactive components, and the first electrodes of the diodes are connected to the second output terminal of the power supply circuit via one of the reactive components. The number of turns of the two reactive components is essentially chosen to equal the number of secondary turns on the transformer. The two reactive components are positioned on each separate core part so that the resulting magnetic flux in common core parts substantially equals the difference between the magnetic flux of the two core parts, and the secondary winding of the transformer is positioned on the common core parts.
    Type: Grant
    Filed: May 13, 1993
    Date of Patent: August 2, 1994
    Assignee: Scanpower
    Inventor: Ole S. Seiersen
  • Patent number: 5132889
    Abstract: The present invention is a circuit and method for reducing switching losses in a full bridge, resonant transition, switching power converter. The converter circuit includes a bridge switching circuit having an FET switch in each leg of the bridge. Each FET has a parasitic drain-to-source capacitance. The primary of a power transformer is connected across the bridge. Two secondary windings of the transformer are connected in a center-tapped configuration. A saturable reactor and a rectifier is connected in series with each secondary winding. A control means controls the conduction interval of the FET switches to produce a first and a second half-cycle of converter operation, each half-cycle including an on-time and a free-wheeling interval. The saturable reactors force unequal current distribution in the secondary windings during the free-wheeling intervals such that a primary current is caused to flow.
    Type: Grant
    Filed: May 15, 1991
    Date of Patent: July 21, 1992
    Assignee: IBM Corporation
    Inventors: Leonard J. Hitchcock, Michael M. Walters, Ronnie A. Wunderlich
  • Patent number: 5126931
    Abstract: A single ended forward DC-to-DC converter is operated with a main switch in series circuit with a primary winding of the isolation transformer and an auxiliary switch for charging a reset capacitor also in circuit with said primary winding. The main switch and auxiliary switch are operated through control logic so that neither switch is ON at the same time. A predetermined dead time is provided between turning OFF the auxiliary switch and turning ON the main switch to allow the output capacitance of the main switch to discharge into the secondary of the transformer. Current discharge into the secondary of the transformer during this time period is limited either by a saturable reactor in series circuit with the secondary or a selectively controlled rectifier.
    Type: Grant
    Filed: September 7, 1990
    Date of Patent: June 30, 1992
    Assignee: ITT Corporation
    Inventor: Ionel Jitaru
  • Patent number: 5086381
    Abstract: A DC-DC converter includes a transformer and a switching element. The primary winding of the transformer and the switching element are connecting in series with a DC power source. A DC output is extracted via a rectifier circuit connected to a secondary winding of the transformer. A capacitor is connected in parallel to the switching element, and a saturable reactor is connected between the secondary winding of the transformer and the rectifier.
    Type: Grant
    Filed: October 9, 1990
    Date of Patent: February 4, 1992
    Assignees: Toko Kabushiki Kaisha, Nemic Lambda Kabushiki Kaisha, Yutaka Electric Mfg. Co., Ltd., Densetsu Corp.
    Inventors: Shigeru Kameyama, Koji Arakawa, Kazushi Watanabe, Hitoshi Yoshioka, Isami Norigoe
  • Patent number: 5065301
    Abstract: A switching power supply for controlling an output voltage to a constant value with respect to fluctuations in input or in load, wherein are provided a DC power supply; two dividing capacitors connected in series to both ends of the DC power supply; two semiconductor switches connected in series to both ends of the DC power supply; a transformer having a primary winding, one end of which is connected to a connecting point of the two dividing capacitors; and a T type circuit comprising two inductors connected in series between the connecting point of the two semiconductor switches and the other end of the primary winding; and a capacitor connected between the connecting point of the two inductors and the other end of the primary winding. The control characteristics of the switching power supply are improved by reducing the dependency of the output voltage on fluctuations in the load.
    Type: Grant
    Filed: July 5, 1990
    Date of Patent: November 12, 1991
    Assignee: Yokogawa Electric Corporation
    Inventors: Masaki Shioya, Masuo Hanawaka
  • Patent number: 4967335
    Abstract: A flyback type power supply has a nominal 12 volt secondary winding that is connected to a rectifier through the primary winding of a saturable transformer. The secondary winding of the saturable transformer is connected in series with the DC load current supplied by the rectifier. A filter capacitor completes the circuit. Under no load conditions, the impedance presented by the primary of the saturable transformer is high and the output voltage developed across the filter capacitor is maintained at about 12.25 volts. Under full load conditions, the impedance presented is negligible.
    Type: Grant
    Filed: September 21, 1989
    Date of Patent: October 30, 1990
    Assignee: Zenith Electronics Corp.
    Inventor: John G. Konopka
  • Patent number: 4931918
    Abstract: A ringing choke converter power supply device comprising a ringing choke converter power supply for stabilizing an output voltage by an indirect feedback system; a variable impedance element provided on a primary or secondary side of the power supply; and a control circuit for transmitting a control signal to the variable impedance element in such a direction that an error signal obtained by comparing the output voltage of the power supply with a predetermined reference voltage becomes zero. The variable impedance element, which is preferably a saturable reactor, is interposed between a voltage detection winding and a feedback diode or between the feedback diode and a capacitor when the element is provided on the primary side; and is interposed between a transformer secondary winding and a rectifier circuit, when the element is provided on the secondary side.
    Type: Grant
    Filed: July 10, 1989
    Date of Patent: June 5, 1990
    Assignee: Yokogawa Electric Corporation
    Inventors: Kiyoharu Inou, Yoshiaki Koide, Yasunobu Iwata
  • Patent number: 4931920
    Abstract: A circuit for regulating the output voltage of a switched mode power supply having a current mode magnetic amplifier includes a current transformer for sensing current flow through the magnetic amplifier. The sensed current is provided to a circuit which includes a resistor for developing a pulsating voltage and a storage capacitor for converting the pulsating voltage to a tracking voltage and storing the tracking voltage. The tracking voltage and a reference voltage are provided to a differential amplifier, the output of which operates a transistor which controls the operation of the magnetic amplifier, thereby regulating the output voltage of the power supply.
    Type: Grant
    Filed: June 16, 1989
    Date of Patent: June 5, 1990
    Assignee: NCR Corporation
    Inventor: Mark P. Barker
  • Patent number: 4930063
    Abstract: A voltage regulator particularly adapted to A.C. distributed power systems requiring independent voltage regulation at a plurality of frequency responsive power supply modules energized by a power source at a common alternating frequency is provided by resonant tuning of the regulator circuit. An LC resonant circuit determines the operating frequency of the regulator, and may be operated above or below the excitation frequency. The output voltage is applied to a current amplifier which energizes a linearly variable inductor in accordance with the sensed D.C. output voltage. Changes in the output voltage result in changes in the tuned frequency of the LC circuit and the corresponding corrective change in the output voltage. Circuits providing both voltage and current regulation are described.
    Type: Grant
    Filed: April 17, 1989
    Date of Patent: May 29, 1990
    Assignee: Unisys Corporation
    Inventors: Christopher P. Henze, Joseph H. Mulkern
  • Patent number: 4916590
    Abstract: A series resonant power supply is switched at a constant frequency above the audio range, in which a magnetic amplifier is used to control the magnitude of the output voltage. It can be run silently, while providing high power at relatively low cost. The power supply includes a full or half bridge rectifying circuit with first and second common terminals. A magnetic amplifier is coupled from the first common terminal to a second common terminal. The magnetic amplifier includes a first primary coil for conducting current from the first common terminal to the second terminal. A secondary coil for generating an output current, and a control coil receiving a control current are coupled with the first primary coil. A second primary coil is connected to conduct current from the second common terminal to the first common terminal. A second secondary coil and a second control coil are coupled with the second primary coil.
    Type: Grant
    Filed: July 6, 1989
    Date of Patent: April 10, 1990
    Assignee: Spectra-Physics
    Inventor: Alan W. Petersen
  • Patent number: 4896091
    Abstract: The power converter (10) serves for conditioning an electricity supply for a load (12), whereby the supply is derived from a power source (11) and is adapted to the requirements of the load (12) in respect of the electrical values. The converter (10) comprises in its simplest version exclusively a transformer (13) and an inductive resistor connected in series with the latter and designated as an actuator (14). This actuator (14) is constructed from two coaxially-arranged, identical and annularly closed variety cores (111, 112), which are individually surrounded by partial windings of an induction winding (150) and jointly by a control winding (117). The latter (117) is joined to a control system (30), which by means of a control current (I) sets an inductivity value (L) of the actuator (14), which can be varied within wide ranges (1.100).
    Type: Grant
    Filed: July 7, 1987
    Date of Patent: January 23, 1990
    Assignee: Hasler AG
    Inventor: Andre Kislovski
  • Patent number: 4849874
    Abstract: A power converter embodying the principles of the invention, and having a positive and negative output utilizes a single magnetic amplifier controller to control two saturable inductor cores utilized to regulate the positive and negative outputs by modulating the positive and negative pulse output of the power converter transformer. The magnetic amplifier controller monitors and sums the two voltage outputs and derives an offset from average representative output signal. This offset from average representative output signal is compared with a reference signal to derive an error signal. A current responsive to the error signal is generated and utilized to periodically reset the two saturable inductor cores and regulate the positive and negative output voltages.
    Type: Grant
    Filed: October 24, 1988
    Date of Patent: July 18, 1989
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Robert J. Buck, Ralph Walk, Pradhuman S. Zaveri
  • Patent number: 4811187
    Abstract: A DC-DC converter having a transformer having a primary winding and a secondary winding; means for supplying DC input voltage to the primary winding; at least one switching element connected between the DC input voltage supplying means and the primary winding; rectifying means; at least one saturable reactor having a first winding and a second winding, the first winding being connected between one end of the secondary winding which is positive while the switching element is in a turn-on state and the rectifying means; and reset control circuit means connected to the second winding of the saturable reactor for supplying reset voltage thereto in response to output voltage of the rectifying means. The first and second windings have such polarities that the reset voltage can reset the saturable reactor during a turn-off period of the switching element. This DC-DC converter enjoys less temperature rise in the saturable reactor and a lower level of noise generation.
    Type: Grant
    Filed: October 20, 1987
    Date of Patent: March 7, 1989
    Assignee: Hitachi Metals Ltd.
    Inventors: Shin Nakajima, Kiyotaka Yamauchi, Osamu Shimoe