Inductance In The Supply Circuit Patents (Class 315/258)
  • Patent number: 8994293
    Abstract: A circuit serving as a power source for light-emitting diode (LED) lighting applications, the circuit comprising a boost converter comprising a pair of boost field-effect transistors (FETs) and a boost inductor coupled to the pair of boost FETs, wherein an input voltage feeding the boost converter has a sinusoidal waveform, and wherein a half cycle of the input voltage is represented by a plurality of time slices, and a controller coupled to the boost converter and configured to determine a current time slice in the plurality of time slices, generate one or more output signals based at least in part on the current time slice and without a need to compute any multiplier function involving the input voltage, and control states of the boost FETs using the one or more output signals.
    Type: Grant
    Filed: November 14, 2013
    Date of Patent: March 31, 2015
    Assignee: Robertson Transformer Co.
    Inventors: Denny D. Beasley, Peter W. Shackle
  • Patent number: 8922131
    Abstract: A light fixture includes a housing, a plurality of parallel lamps, and a ballast. The ballast provides power to each lamp of the plurality of parallel lamps. A series resonant inverter in the ballast provides AC power to an output of the series resonant inverter from a DC power source having a power rail and a ground. The series resonant inverter includes a resonant inductor, a first clamping diode, and a second clamping diode. The resonant inductor has a first portion and a second portion and a connection point between the first portion and the second portion. The first clamping diode is connected between the connection point and the power rail. The second clamping diode is connected between the connection point and the ground. The first and second clamping diodes ensure soft switching of a half-bridge inverter switch pair of the series resonant inverter.
    Type: Grant
    Filed: July 25, 2012
    Date of Patent: December 30, 2014
    Assignee: Universal Lighting Technologies, Inc.
    Inventor: Wei Xiong
  • Publication number: 20140015437
    Abstract: A method and circuit with a pulsed current sink for driving one or more than one light-emitting diodes with a pulsed current. In the field of lighting applications, the present invention provides a switching-mode pulsed current supply circuit for driving white light-emitting diodes able to provide higher perceived brightness levels than existing light-emitting diode drivers. Another aspect of the present invention provides switching mode pulsed current supply circuits for driving light-emitting diodes having the advantage that the pulse width and the magnitude of the pulsed current supplied to the light-emitting diodes can be controlled independently.
    Type: Application
    Filed: July 15, 2012
    Publication date: January 16, 2014
    Inventor: Wen-Hsiung Hsieh
  • Publication number: 20130049613
    Abstract: An apparatus and method for reducing the perception of flicker of solid state light sources. An alternating current (AC) signal is passed through an AC conditioning circuit and a passive resonating circuit before being supplied to a string of solid state light sources, such as light emitting diodes.
    Type: Application
    Filed: August 23, 2012
    Publication date: February 28, 2013
    Applicant: EXPRESS IMAGING SYSTEMS, LLC
    Inventor: William G. Reed
  • Publication number: 20120062139
    Abstract: An illumination assembly, comprising: at least one luminous means having at least one luminescence diode chip as light source, and at least one energizing means, which is connected to the at least one luminous means via a connecting line, wherein the energizing means is designed to energize the at least one luminous means.
    Type: Application
    Filed: February 2, 2010
    Publication date: March 15, 2012
    Applicant: Traxon Technologies Europe Gmbh
    Inventors: Holger Ruether, Dirk Beiner
  • Publication number: 20110298388
    Abstract: A light driver circuit device for synchronously driving a plurality of cold cathode fluorescent lamps (CCFLs) is provided. The light driver circuit device includes an inverter circuit board and a balance circuit board. The inverter circuit board has an inverter circuit coupled to a driving signal for outputting a driving voltage to drive the CCFLs synchronously. The balance circuit board and the inverter circuit board are installed separately, and the balance circuit board has a balance circuit coupled to a terminal of each CCFL and the inverter circuit. The CCFL driving architecture is designed to install the inverter circuit and the balance circuit individually, thus effectively reducing the space of the driving circuit and the total cost of the circuit design. Furthermore, the balance circuit board can balance the current in each CCFL effectively, and there is no limitation to where the balance circuit board can be disposed.
    Type: Application
    Filed: August 17, 2011
    Publication date: December 8, 2011
    Applicant: AU OPTRONICS CORPORATION
    Inventors: Cheng-Neng Liao, Chia-Hung Sun, Huang-Ti Lin, Chin-Chuang Chueh
  • Publication number: 20110291582
    Abstract: The invention is disclosed a lighting device using an alternating current to drive light emitting diodes (LEDs). The lighting device uses at least two parallel-connected LED modules. In front of each LED module has connected to a current balancing unit in series that has same capacitance or inductance. The LED module comprises a first polarity LED bar and a second polarity LED bar connected in parallel. The LED module receives an alternating current voltage from the current balancing unit, which alternatively drive the first polarity LED bar and the second polarity LED bar. The light device uses different impedances of the current balancing unit and the LED to provide smooth and uniform current to the LED module and achieves a stable luminance.
    Type: Application
    Filed: September 22, 2010
    Publication date: December 1, 2011
    Inventors: Tao-Chin WEI, Yuan-Ping Liu
  • Publication number: 20110285988
    Abstract: An illumination module that may include a LED driver; a strip cable comprising multiple conductors that have a high ratio form factor and a low impedance and a low inductance factor; the forms factor is a ratio between a width of the strip cable and a thickness of the strip cable; a group of light emitting diodes (LEDs) that comprises at least one LED; the group of LED is coupled to the LED driver via the strip cable; wherein the LED driver is arranged to activate the group of LEDs by driving a high current short duration driving signal via the strip cable; and wherein the group of LEDs is arranged to emit at least one light pulse in response to the high current short duration driving signal.
    Type: Application
    Filed: May 18, 2011
    Publication date: November 24, 2011
    Inventors: Amnon Menachem, Yossi Cherbis, Arnon Ben Natan
  • Publication number: 20100327762
    Abstract: The present invention relies on polyphase alternating current power with phase difference or direct current power rectified from polyphase alternating current power to drive a common electric energy-driven luminous body; or to separately drive proximately installed individual electric energy-driven luminous bodies so that the pulsation of the outwardly projected light is reduced.
    Type: Application
    Filed: June 29, 2009
    Publication date: December 30, 2010
    Inventor: Tai-Her Yang
  • Publication number: 20090179580
    Abstract: The present invention uses capacitive, inductive, or resistive impedance to constitute the first impedance, and the capacitive and inductive impedances in parallel connection which will not produce parallel resonance to constituted the second impedance, and is characterized in that the first and second impedance in series connection is configured for inputting pulsed power, thereby to form a bi-directional power in decaying wave shape at the two ends of the second impedance to drive the bi-directional conducting light emitting diode.
    Type: Application
    Filed: January 12, 2009
    Publication date: July 16, 2009
    Inventor: Tai-Her Yang
  • Patent number: 5854539
    Abstract: An electroluminescent lamp is driven by a driving circuit that can supply an approximately sinusoidal signal, a bi-directional sawtooth signal or a single-ended sawtooth signal. Switches selectively transfer energy from a battery to an inductor and then from the inductor to the lamp. In one embodiment, the lamp voltage is compared to a reference waveform, such as a sinusoid. The switches are activated responsive to the error between the lamp voltage and reference waveform to minimize the error. The lamp can thus be driven with a closer approximation of the reference waveform.
    Type: Grant
    Filed: August 26, 1997
    Date of Patent: December 29, 1998
    Assignee: StMicroelectronics, Inc.
    Inventors: Ermanno Pace, Giorgio Mariani, Alessandro Fasan
  • Patent number: 5446350
    Abstract: An impedance matching circuit for a self-oscillating electrodeless fluorescent lamp ballast of the type having an inductor connected in series with the parallel combination of a capacitor and the lamp's drive coil includes an additional capacitor connected in series with the drive coil. The capacitance value chosen for the additional capacitor is dependent on: stresses on the parallel capacitor; matching the impedance of the ballast; and the impact of the capacitor on the loaded coil phase angle. The additional capacitor reduces the phase angle presented to the ballast, thereby lowering the sensitivity of the ballast to component and lamp variations. In addition, the overall impedance of the network is reduced, such that the required inductance of the series inductor is reduced; hence, the inductor can have fewer turns and lower conduction losses.
    Type: Grant
    Filed: April 18, 1994
    Date of Patent: August 29, 1995
    Assignee: General Electric Company
    Inventors: Sayed-Amr El-Hamamsy, Gerald W. Ludwig, David O. Wharmby, Louis R. Nerone
  • Patent number: 5276385
    Abstract: The invention provides a high-pressure discharge lamp incorporating an outer envelope storing a pair of electric terminals a plurality of arc tubes which are respectively stored in this outer envelope and electrically connected in parallel, and a plurality of ignition aids available for assisting operating of these arc tubes, where these ignition aids are provided for each of these arc tubes and contain potentials different from each other. In addition, the invention also provides a lighting system for operating the high-pressure discharge lamp.
    Type: Grant
    Filed: September 25, 1991
    Date of Patent: January 4, 1994
    Assignee: Toshiba Lighting & Technology Corporation
    Inventors: Akira Itoh, Kazuyoshi Okamura, Kazuiki Uchida, Mitsuho Kotabe, Hirochika Shiohama, Kimihito Sato, Yasuki Mori, Katsusuke Uchino
  • Patent number: 5036255
    Abstract: In accordance with the present invention, a control device for energizing a lamp circuit including gaseous discharge lamps includes a power source having a variable amplitude varying in time. A control circuit is provided for producing a variable pulse width control signal. A switch is responsive to the variable pulse width control signal for providing a switched output from the power source. The switched output has a pulse width proportional to the variable pulse width control signal for supplying power to the lamp circuit. An inductor is interconnected between the switch and the lamp circuit. The inductor includes a first winding with a center tap for receiving the switched output from the switch for balancing the voltage and current applied to the lamps within the lamp circuit. The inductor further includes a second winding connected to the lamp circuit for providing constant lamp brightness regardless of amplitude variations in the source voltage.
    Type: Grant
    Filed: April 11, 1990
    Date of Patent: July 30, 1991
    Inventors: William E. McKnight, deceased, by Eileen M. McKnight, executrix
  • Patent number: 4996463
    Abstract: An auxiliary lighting system to be used with a high intensity discharge lamp having a solid state or electronic ballast. An auxiliary lamp is connected to a source of power through the normally closed contacts of a relay. The relay coil is in the input line to the solid state ballast. Above a predetermined threshold current to the ballast, the relay coil causes the normally closed contacts to open thereby extinguishing the auxiliary lamp. When the high intensity discharge lamp is turned on, or when there is an interrupt, the power requirements for the HID lamp are at a low point. Thus the input current to the solid state ballast is below the threshold, the contacts are closed and the auxiliary lamp is turned on.
    Type: Grant
    Filed: August 21, 1989
    Date of Patent: February 26, 1991
    Inventor: Victor Horowitz
  • Patent number: 4931699
    Abstract: This ballast system for a gaseous discharge lamp comprises a reactor coil and core structure forming a magnetic circuit for flux developed by power-frequency current through the coil during lamp operation. The core comprises a leg surrounded by the reactor coil, two yokes at opposite ends of the leg, and flux-return structure connected between the two yokes radially outside the coil. For developing a high-voltage, high-frequency pulse for initiating lamp operation, there is provided an ignitor coil surrounding the flux-return structure and the reactor coil and inductively coupled to the reactor coil with respect to high-frequency pulse components.
    Type: Grant
    Filed: January 6, 1989
    Date of Patent: June 5, 1990
    Assignee: General Electric Company
    Inventor: David W. Knoble
  • Patent number: 4902943
    Abstract: A plug-in starting aid for generating high voltage pulses in the ballast circuit of high intensity discharge lamp comprises interconnected electrical components mounted in a frame of insulating material. The frame has three terminals projecting out one side and engageable in the cooperating terminals of a connector block in which the starting in may be plugged in. The terminals are also engageable by standard mating wire terminals when the starting aid is used without a connector block.
    Type: Grant
    Filed: May 23, 1989
    Date of Patent: February 20, 1990
    Assignee: General Electric Company
    Inventors: Judith A. Nicholson, Omer E. Murray, Jr., Carl D. Taylor
  • Patent number: 4654563
    Abstract: A circuit containing a ballast for one or more fluorescent lamps. The circuit includes a first inductor in series with a voltage input terminal and a first capacitor to form a series resonant circuit to provide a starting voltage to the lamps. A second, shunt inductors coupled between the first inductor and the capacitor and another input terminal of the circuit to eliminate the high Q of the series resonant circuit and prevent the first inductor from saturating. The inductors are mounted on the legs of an H-shaped core to provide inductive coupling between the inductors and allow a maximum winding area for the first inductor to reduce the series resistance of the lamp current path. The core also allows the shunt inductor to adjust power line power factor independently of lamp power factor. Improvements in system efficiency of up to 15% can be achieved over conventional core/coil type ballasts.
    Type: Grant
    Filed: March 28, 1984
    Date of Patent: March 31, 1987
    Assignee: Energy Technologies Corp.
    Inventor: Gerald D. Boyd
  • Patent number: 4392089
    Abstract: A frequency responsive power control system includes an improved isolator in series electrical connection with respect to a ballasted lamp load. The isolator has a high inductive impedance at low current for blocking ballast induced noise signals from interferring with proper operation of frequency responsive switching circuits in the system. In a particularly useful embodiment, the isolator is inductively matched to the capacitive characteristic of the ballasted lamp load so that the isolator-load circuit combination is resonant at a frequency sufficiently removed from any of the control system activation frequencies so as to block any noise signals induced by the ballasted load which might otherwise cause undesired activation of the switching circuits and flickering of the ballasted lamp loads. Under saturation current, with the switching circuit conducting, the isolator functions collectively with the load to provide an impedance which blocks control signals from reaching the load.
    Type: Grant
    Filed: July 20, 1981
    Date of Patent: July 5, 1983
    Assignee: GTE Products Corporation
    Inventors: James N. Lester, Lee A. Prager
  • Patent number: 4323823
    Abstract: Unitary ballast structure for starting and operating four fluorescent lamps comprising stacked magnetic iron laminations and coils retained thereon to provide two separate inductor means and a transformer means for heating multiple lamp electrode coils. The magnetic structure comprises a core member having a shell-type configuration with two main legs and six coil legs which define five coil-receiving windows. Coils retained on the second and third coil legs each comprise inductor means and occupy the first, second and third windows. An electrode-coil-heating transformer means is retained on the fifth coil leg and occupies the fourth and fifth windows. Each of the laminations which comprise the magnetic structure can have the same configuration which facilitates manufacture. Magnetic coupling between the different electrical components comprising the ballast structure is minimized, while still providing a compact, unitary ballast.
    Type: Grant
    Filed: May 16, 1980
    Date of Patent: April 6, 1982
    Assignee: Westinghouse Electric Corp.
    Inventor: Rao L. Boggavarapu
  • Patent number: 4190790
    Abstract: An isolator circuit for use with a switching circuit for energizing a ballasted load in response to a control signal of preselected frequency superimposed on AC power circuits which supply the load. In the switching circuit, a triac is gated to conduct the AC power to the load by a circuit including an impedance element and a series resonant LC network tuned to the frequency of the control signal. The control signal may be one of a plurality of control signals having different frequencies superimposed on the power circuits. The isolator circuit is connected between the traic and the load and comprises a plurality of series connected parallel resonant LC circuits each tuned to block a respective one of the control signals. A series choke blocks spurious signal voltages.
    Type: Grant
    Filed: December 29, 1978
    Date of Patent: February 26, 1980
    Assignee: GTE Sylvania Incorporated
    Inventors: John L. Plumb, Sheppard Cohen, Paul H. Ingalls
  • Patent number: 4163925
    Abstract: A two-wire ballast arrangement is disclosed for fluorescent tubes having first and second terminals for supplying variable power to dim the fluorescent tube, a choke coil connected between the first terminal and the fluorescent tube and a filament transformer having a primary connected between the second terminal and a tap on the choke coil, the tap being selected to supply substantially constant voltage to the primary winding, the transformer having secondary windings to supply filament voltage to the fluorescent tube.
    Type: Grant
    Filed: February 6, 1978
    Date of Patent: August 7, 1979
    Assignee: Honeywell Ltd.
    Inventor: Zoltan L. Gyursanszky
  • Patent number: 4123690
    Abstract: Electrical ballast circuit of improved power factor for operating gaseous discharge lamps. Two discharge lamps are respectively connected to two inductively coupled induction coils for obtaining high power factor without the use of capacitors.
    Type: Grant
    Filed: March 7, 1977
    Date of Patent: October 31, 1978
    Assignee: General Electric Company
    Inventor: Mitchell M. Osteen
  • Patent number: 3997814
    Abstract: A discharge lamp lighting device minimized in dimensions and capable of lighting a discharge lamp with a source voltage close to discharge lamp voltage is provided. The device comprises an alternating current source, a discharge lamp connected in series with the alternating current source through a current limiting means and of a lamp voltage substantially equal to the source voltage, and a switching element connected substantially in parallel with the lamp. The switching element is actuated once in each of half cycles of the source voltage so that, when the element is in ON-state, an energy will be accumulated in the current limiting means and, when the element is in OFF-state, such accumulated energy will be exhausted to the discharge lamp, whereby the lamp is continuously lighted.
    Type: Grant
    Filed: March 21, 1975
    Date of Patent: December 14, 1976
    Assignee: Matsushita Electric Works, Ltd.
    Inventor: Makoto Toho
  • Patent number: 3991344
    Abstract: A lighting control apparatus to provide variable intensity light from high pressure discharge lamps using two high pressure discharge lamp loads connected in series to provide more widely variable intensity of light. The outputs of two ballasts may be connected in series to feed the series connected discharge lamp load. Preferably a feedback signal proportional to load current is used to stabilize operation. In addition, circuitry is preferably provided to maintain a predetermined minimum current to prevent extinguishing of the lamps from low current and "hot restrike" circuitry is provided to limit the maximum load voltage when the lamps are extinguished.
    Type: Grant
    Filed: March 18, 1975
    Date of Patent: November 9, 1976
    Assignee: Westinghouse Electric Corporation
    Inventor: James B. Tabor
  • Patent number: 3989976
    Abstract: Lighting control apparatus for controlling the light intensity of high-intensity-discharge (HID) lamps operated from an AC source while eliminating the tendency for such lamps to extinguish during the dimming thereof. The apparatus comprises a variable reactive ballast controlled with respect to its reactance by a solid-state switching device which is responsive to a timed control signal provided by a signal generating device operating from the same AC source. A lamp voltage sensing device develops a feedback signal which varies in accordance with the voltage drop across the lamps being ballasted. A signal sensing and overriding device combines the feedback signal and the timed controlled signal and causes the feedback signal to override the timed control signal before the lamp voltage reaches such value as might cause the lamp to extinguish.
    Type: Grant
    Filed: October 7, 1975
    Date of Patent: November 2, 1976
    Assignee: Westinghouse Electric Corporation
    Inventor: James B. Tabor
  • Patent number: 3931543
    Abstract: Circuits are disclosed for starting and operating a high pressure sodium vapor lamp in combination with another gaseous discharge lamp of low voltage breakdown characteristics. The sodium vapor lamp is connected in series with a ballast induction coil, while the low voltage breakdown lamp, a portion of the ballast coil at its input side, and a capacitor are connected in a series discharge loop to produce high frequency, high voltage pulses for starting the sodium vapor lamp, and providing for operation of both lamps. A ballast capacitor is connected in series with the low voltage lamp to provide a lead ballast circuit therefor.
    Type: Grant
    Filed: September 30, 1974
    Date of Patent: January 6, 1976
    Assignee: General Electric Company
    Inventor: Joe A. Nuckolls
  • Patent number: RE31146
    Abstract: A two-wire ballast arrangement is disclosed for fluorescent tubes having first and second terminals for supplying variable power to dim the fluorescent tube, a choke coil connected between the first terminal and the fluorescent tube and a filament transformer having a primary connected between the second terminal and a tap on the choke coil, the tap being selected to supply substantially constant voltage to the primary winding, the transformer having secondary windings to supply filament voltage to the fluorescent tube.
    Type: Grant
    Filed: March 2, 1981
    Date of Patent: February 8, 1983
    Assignee: Honeywell Ltd.
    Inventor: Zoltan L. Gyursanszky