Patents Examined by Zekre Tsehaye
  • Patent number: 8547714
    Abstract: There are provided an output inverter for single phase which can detect a current with high precision through a smaller number of components, and an output current detecting method thereof. A first current detector (6) is disposed between a positive electrode P side of a DC power supply and a parallel connector (1) in a first arm (8), a second current detector (7) is disposed between a negative electrode N side of the DC power supply and a parallel connector (4) in a second arm (9), a current in a first convection mode is detected by the first current detector (6), a current in a second convection mode is detected by the second current detector (7), and an output current is detected from signals output from the first current detector (6) and the second current detector (7).
    Type: Grant
    Filed: December 25, 2006
    Date of Patent: October 1, 2013
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventor: Masato Higuchi
  • Patent number: 8541990
    Abstract: A power conversion controller having a novel power factor correction mechanism, including: a normalization unit, used to generate a normalized signal according to a line voltage by multiplying the line voltage with a normalizing gain, wherein the normalizing gain is proportional to the reciprocal of the amplitude of the line voltage; a reference current generation unit, coupled to the normalization unit to generate a reference current signal by performing an arithmetic operation, wherein the arithmetic operation involves the normalized signal; and a gate drive signal generation unit, used to generate a gate drive signal, wherein the duty of the gate drive signal is determined by a voltage comparison of the reference current signal and a current sensing signal.
    Type: Grant
    Filed: November 23, 2010
    Date of Patent: September 24, 2013
    Assignee: Immense Advance Technology Corp.
    Inventors: Ko-Yen Lee, Chia-Chieh Hung, Wei-Chuan Su
  • Patent number: 8537580
    Abstract: A controller that controls a switching element of an inverter using pulse width modulation is applied to a power converter including an inverter, to realize a stable change of a carrier frequency, current control responsiveness, and inverter loss suppression. The controller includes a carrier-frequency setting unit that sets a carrier frequency command used for pulse width modulation of an inverter corresponding to a current command and a current-command change rate. The carrier-frequency setting unit includes a carrier frequency map having mapped thereon information of a carrier frequency corresponding to a current command expressed in a vertical axis and a current-command change rate expressed in a lateral axis, and outputs information of a carrier frequency on the carrier frequency map corresponding to the input current command and the input current-command change rate to a switching pattern calculator.
    Type: Grant
    Filed: January 18, 2008
    Date of Patent: September 17, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventors: Shinichi Furutani, Akira Satake, Jun Sawaki
  • Patent number: 8531852
    Abstract: A method of controlling at least one voltage converter having a plurality of cells in series, comprising an AC part and a DC part, characterized in that the AC input voltage (Vei) of each cell is determined directly by the use of a high speed current control loop relating to the AC part and a lower speed voltage control loop relating to the cells, the method including choosing the following voltage control law: ? i = C i 2 ? ( 2 R pi ? C i ? Z i + ? ? t ? Z i ? ? _ ? ? ref - K 1 ? Zi - K 2 ? Zi ? sign ? ( E Zi ) ) where: K1zi and K2zi are positive adjustment gains; Ci is the continuous capacitance of the capacitor Ci of each cell; Rpi is the losses associated with each cell; Zi—ref is the reference value of Zi=(UDCi)2, UDCi; being the direct voltage across the capacitor Ci; and EZi is such that EZi=Zi?Zi—ref.
    Type: Grant
    Filed: October 19, 2009
    Date of Patent: September 10, 2013
    Assignee: Alstom Grid SAS
    Inventors: Abdelkrim Benchaib, Serge Poullain
  • Patent number: 8519688
    Abstract: Consistent with an example embodiment, there is method and a controller for controlling burst mode operation of a switched mode power supply (SMPS). It also relates to switched mode power supplies comprising such a controller. One way to increase the efficiency of a switched mode power supply is to operate it at a power level close to the optimum efficiency point for a brief period, followed by a period where the power supply is not switching during which no energy is wasted. This type of operation is known as “burst mode” and results in high efficiency at low power levels.
    Type: Grant
    Filed: April 27, 2011
    Date of Patent: August 27, 2013
    Assignee: NXP B.V.
    Inventor: Hans Halberstadt
  • Patent number: 8508211
    Abstract: Method and system for developing low noise bandgap references. A stacked ?VBE generator is disclosed for generating ?VBE. The stacked ?VBE generator includes an error amplifier configured to generate an output based on an error signal provided by a first stack of the ?VBE generator. The first stack of the ?VBE is coupled to a first sub-circuit and the error amplifier to form a closed loop. The first sub-circuit is coupled to a power supply and ground and configured to provide a source current between the power supply and the ground. The stacked ?VBE generator also includes a second sub-circuit coupled to the output of the error amplifier, the first and second stacks, and the ground, as well as a second stack of the ?VBE generator, which is coupled to the first stack and the second sub-circuit. The ?VBE is measured at outputs of the first and second stacks and equals the sum of individual ?VBEs of the first and second stacks.
    Type: Grant
    Filed: November 12, 2009
    Date of Patent: August 13, 2013
    Assignee: Linear Technology Corporation
    Inventor: Michael Brian Anderson
  • Patent number: 8493756
    Abstract: Provided is a switching control method of a transformer coupled booster to suppress an increase in energizing current in a transformer of the transformer coupled booster and downsize the transformer coupled booster. A primary coil current that flows through a primary coil of the transformer, and a secondary coil current that flows through a secondary coil of the transformer are detected. The current difference between the detected primary coil current and the detected secondary coil current is calculated. Based on the calculated current difference, the cycle of ON/OFF periods of four arms provided on the transformer coupled booster is maintained at a constant level. Control is carried out so that the ratio of the first arm's ON period to the OFF period is always equal to the ratio of the third arm's ON period to the OFF period.
    Type: Grant
    Filed: March 19, 2009
    Date of Patent: July 23, 2013
    Assignee: Komatsu Ltd.
    Inventor: Atsushi Moki
  • Patent number: 8462526
    Abstract: A power converter enhances conversion efficiency from DC power to AC power. A first chopper circuit chops DC voltage from a photovoltaic panel at a system frequency producing a first square-wave whose voltage level changes positively. A second chopper circuit chops the first square-wave at a frequency double the system frequency producing a second square-wave whose voltage level changes negatively and adds the first square-wave and the second square-wave to produce a third square-wave that changes positively and negatively in a sine-wave manner. A third chopper circuit charges and discharges by chopping the third square-wave at a third frequency fixed by timing according to a difference between the third square-wave and a sine-wave voltage. PWM control is performed on the charge and discharge outputs such that the difference is corrected, producing a sine-wave voltage that continuously changes positively and negatively. A spike noise of an output voltage is suppressed.
    Type: Grant
    Filed: February 24, 2011
    Date of Patent: June 11, 2013
    Assignee: OMRON Corporation
    Inventors: Masao Mabuchi, Kazuyoshi Imamura, Mio Miyamoto, Kohei Takahashi
  • Patent number: 8456865
    Abstract: A microinverter is provided for converting DC energy from a PV panel into a grid-compatible AC signal. A first plurality of switching elements is coupled between a DC energy source and a primary winding of a transformer. A second plurality of switching elements is coupled to a secondary winding of the transformer. Current sensors sense real time converter parameters including a DC input, an AC output, and a primary current. A digital controller determines an operating mode for the converter based on a DC input signal, with the controller further including a switch signal generator circuit configured to adjust switching states. The switch state adjustments are based on the operating mode, real time converter parameters which include the DC input signal, an AC signal for output to a grid, a primary current, and a desired shape for the AC output signal waveform.
    Type: Grant
    Filed: June 17, 2010
    Date of Patent: June 4, 2013
    Assignee: Power-One, Inc.
    Inventors: Andrea Bianchi, Massimo Valiani
  • Patent number: 8441822
    Abstract: In order to improve the efficiency of a Power Factor Convertor (PFC) first stage to a AC-DC converter the switching cell is split into two smaller ones (each comprising a switched inductor with an output diode). Below a certain load only one cell is active. The second cell only becomes active, out of phase with the first, but not generally in antiphase, after a predefined load level is surpassed in such a way that above that level the first cell has a fixed on time and the second cell a variable one.
    Type: Grant
    Filed: July 1, 2010
    Date of Patent: May 14, 2013
    Assignee: NXP B.V.
    Inventors: Humphrey de Groot, Hans Halberstadt
  • Patent number: 8432052
    Abstract: The present techniques include methods and systems for operating a wind power system to maintain a lifespan of the rotor side converter. In some embodiments, the current of the rotor side converter may be minimized to reduce the stress and/or junction temperature variation in the switching transistors and bond wires of the converter. More specifically, embodiments involve using a minimal current in the rotor side converter based on the rotor side and grid side reactive powers. If the grid side reactive power is greater than a maximum grid side reactive power, the grid side reactive power may be reduced. Further, if the total reactive power does not meet the grid reactive power requirements, the minimal current in the rotor side converter may be adjusted such that the system may sufficiently power the grid.
    Type: Grant
    Filed: May 27, 2010
    Date of Patent: April 30, 2013
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Haihui Lu, Lixiang Wei, Richard A. Lukaszewski, Russel J. Kerkman, Zhenhuan Yuan
  • Patent number: 8432656
    Abstract: A feedback control method of a pulse width modulator (PWM) voltage converter may include generating a control voltage as a sum of an offset voltage and an error signal representing a difference between a scaled replica of a regulated output voltage of the voltage converter and a reference voltage, comparing the control voltage with a ramp signal, the comparing operation generating PWM driving signals for the voltage converter, comparing the regulated output voltage of the voltage converter with an overshoot threshold, and reducing the control voltage when the overshoot threshold is exceeded.
    Type: Grant
    Filed: June 9, 2010
    Date of Patent: April 30, 2013
    Assignee: STMicroelectronics S.r.l.
    Inventor: Osvaldo Enrico Zambetti
  • Patent number: 8427131
    Abstract: Regulation of a remote load center voltage from a local location of a voltage regulator and a voltage regulator control using voltage measurements from the remote load center obtained using a metering device at the load center in communication with the voltage regulator control. The metering device may obtain remote voltage information at the load center and communicate such to the voltage regulator control using a direct communications line, a wide area network, or the like. The communications may include electrical (e.g. copper cable), light (e.g. infrared over fiber optics), radio frequency, or the like. The voltage regulator control may be configured to use local measurements and a line drop compensation algorithm in the event that the remote voltage information becomes unavailable.
    Type: Grant
    Filed: June 12, 2009
    Date of Patent: April 23, 2013
    Assignee: Schweitzer Engineering Laboratories Inc
    Inventors: Michael B. Bryson, David E. Whitehead
  • Patent number: 8411466
    Abstract: The present invention includes: a plurality of switching elements connected in series and connected between two ends of a DC power supply; a first control circuit to alternately turn on and off the switching elements in response to a constant oscillation frequency signal; a series circuit including a primary winding of a transformer and a capacitor connected together in series, and being connected to a connecting point between the switching elements, and to an end of the DC power supply; a rectifying/smoothing circuit to rectify and smooth a voltage in a secondary winding of the transformer thereby to output a DC voltage; a control switching element connected to two ends of the primary or secondary winding of the transformer; and a second control circuit to control the DC voltage at a predetermined voltage by turning on and off the control switching element.
    Type: Grant
    Filed: June 28, 2010
    Date of Patent: April 2, 2013
    Assignee: Sanken Electric Co., Ltd.
    Inventor: Hiroshi Usui
  • Patent number: 8410768
    Abstract: A power supply having an input and an output, includes a power converter coupled between the input and output of the power supply including at least one switch that is controlled by comparing a sensed voltage, the sensed voltage corresponding to a current flowing through the switch, to a reference voltage. A controller, in response to a change detected in a switching frequency of the switch, reduces audible noise generated by the power supply by at least one of: adjusting the reference voltage; adjusting the current sense voltage; or adjusting a resistance used to generate the sensed voltage.
    Type: Grant
    Filed: January 19, 2010
    Date of Patent: April 2, 2013
    Assignee: Delta Electronics, Inc.
    Inventors: Laszlo Huber, Milan M. Jovanović, Chien-Chung Chang
  • Patent number: 8400787
    Abstract: The configurations of a resonant converter system and a controlling method thereof are provided. The proposed resonant converter system includes a resonant converter receiving an input voltage for outputting an output voltage, a rectifying device having a first rectifying switch and a synchronous rectification control circuit coupled to the resonant converter and including a signal generation apparatus generating a weighted turn-off signal to turn off the first rectifying switch at a zero crossing point of a first current flowing through the first rectifying switch.
    Type: Grant
    Filed: October 6, 2011
    Date of Patent: March 19, 2013
    Assignee: Delta Electronics, Inc.
    Inventors: Hongyang Wu, Bin Wang, Jianhong Zeng, Jianping Ying, Xiaoni Xin
  • Patent number: 8379421
    Abstract: When a commercial power supply E operates normally, converter sections PFC1, PFC2 connected in parallel to each other can operate to approximate the input current from the commercial power supply E to the waveform and phase of the input voltage to correct a power factor while supplying stabilized output voltages Vo1, Vo2 to a load. When the voltage of the commercial power supply E drops, the smoothing capacitor Co1 operates as an input power supply to power the converter section PFC2, which allows the smoothing capacitor Co2 to supply the stabilized output voltage Vo2 to the load.
    Type: Grant
    Filed: February 24, 2010
    Date of Patent: February 19, 2013
    Assignee: Oita University
    Inventor: Kimihiro Nishijima
  • Patent number: 8379419
    Abstract: A soft-stop overvoltage protection circuit, into which a soft-stop overvoltage detection voltage proportional to a direct current output voltage is input, reduces the output of a multiplier in accordance with the soft-stop overvoltage detection voltage when the soft-stop overvoltage detection voltage exceeds a first threshold value. An overvoltage protection circuit, a second threshold value higher than the first threshold value being set, compulsorily turns off a switching element by outputting an overvoltage detection signal when the soft-stop overvoltage detection voltage exceeds the second threshold value. The soft-stop overvoltage protection circuit compulsorily increases the output of a voltage error amplifier circuit on the output voltage decreasing. When the output of the voltage error amplifier circuit increases suddenly, and the output voltage rises excessively, the soft-stop overvoltage protection circuit decreases the output of the multiplier, thus curbing the rise of the output voltage.
    Type: Grant
    Filed: November 22, 2010
    Date of Patent: February 19, 2013
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Jun Yabuzaki, Jian Chen
  • Patent number: 8378652
    Abstract: A voltage controlled current source circuit is utilized to clamp the internal compensation node of a low dropout (LDO) regulator with an NMOS output during load transients. The circuit senses a voltage drop of the internal node and mirrors its current to the internal node to hold the internal node voltage when the voltage starts to drop low enough to turn off the output transistor.
    Type: Grant
    Filed: December 23, 2008
    Date of Patent: February 19, 2013
    Assignee: Texas Instruments Incorporated
    Inventor: Yong Xie
  • Patent number: 8378658
    Abstract: A semiconductor device, circuit, and AC and DC load switch for maintaining a small input-output differential voltage and providing a defined response. The load switch can include a pass element coupled to an input terminal and an output terminal. The pass element can include a control terminal, with the control terminal controlling a response of the pass element. The load switch can include a first loop coupled to the control terminal configured to control a voltage drop between the input terminal and the output terminal while maintaining high impedance with the pass element. The load switch can include a second loop coupled to the control terminal configured to provide a defined filter response from the input terminal. The defined response can be a low pass response, high pass response, or a band pass response. The passband and/or stopband of the response can be programmed.
    Type: Grant
    Filed: June 25, 2010
    Date of Patent: February 19, 2013
    Assignee: Micrel, Inc.
    Inventor: David Schie