Patents Examined by Bao Q. Vu
  • Patent number: 8542511
    Abstract: A single-phase voltage source AC/DC converter according to the present invention generates a second axis voltage command from difference between a DC voltage detection value at a DC terminal and a DC voltage command value and controls a DC voltage by increasing and decreasing active power with the second axis voltage command. For example, the voltage at the DC terminal is increased by decreasing active power when the DC voltage detection value at the DC terminal is lower than the DC voltage command, while the DC voltage detection value at the DC terminal is decreased by increasing the active power when the DC voltage detection value at the DC terminal is higher than the DC voltage command.
    Type: Grant
    Filed: December 19, 2011
    Date of Patent: September 24, 2013
    Assignee: Origin Electric Company, Limited
    Inventors: Masaaki Ohshima, Shuichi Ushiki, Jinbin Zhao
  • Patent number: 8542064
    Abstract: Methods and apparatus to control power in a printer are disclosed. An example apparatus includes a first field effect transistor having a first terminal, a second terminal, and a third terminal, the second terminal coupled with a first voltage input. The example apparatus further includes a second field effect transistor having a fourth terminal, a fifth terminal, and a sixth terminal, the fourth terminal coupled with the first terminal of the first field effect transistor, the fifth terminal coupled with a second voltage input. The example apparatus further includes a first comparator having a first input coupled to the first input voltage, having a second input coupled to the second input voltage, and having an output coupled with the third terminal.
    Type: Grant
    Filed: October 31, 2011
    Date of Patent: September 24, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Barley Mark Hirst
  • Patent number: 8542506
    Abstract: A power isolation system and method is disclosed. The system includes a transformer suitable for use in the power isolation system, and a semiconductor device electrically connected to the transformer to provide a reduction of the inrush current associated with powering the transformer, wherein the semiconductor device is activated upon power up based upon the previous shutdown state of the power isolation system to provide a soft start to the transformer, and after activation of the transformer, the semiconductor device is shorted in the system.
    Type: Grant
    Filed: November 16, 2009
    Date of Patent: September 24, 2013
    Assignee: Middle Atlantic Products, Inc.
    Inventors: Robert Schluter, Bernard P. O'Kane, Brendan K. Walsh, Steve Kaufer
  • Patent number: 8542505
    Abstract: A voltage source converter station including a multilevel voltage source converter, for conversion of electrical power between AC and DC, and a control system. The voltage source converter includes a plurality of switching cells including switchable semiconductors, and the control system includes at least one main control unit for providing a voltage reference signal and a plurality of cell control units. Each cell control unit uses carrier based pulse width modulation for controlling the switching of a respective cell, where the main control unit is communicatively connected to the cell control units and provides the reference voltage signal to each cell control unit and each cell control unit creates a switching signal to each respective switching cell using the reference voltage signal and a carrier signal to effectuate the conversion.
    Type: Grant
    Filed: November 30, 2012
    Date of Patent: September 24, 2013
    Assignee: ABB Technology AG
    Inventor: Ying Jiang-Hafner
  • 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: 8525502
    Abstract: A digital pulse controller uses digital logic to send pulses to a high side and low side switches of a switch-mode power supply converter. The digital logic uses a pulse frequency mode which includes a frequency targeting mode and an ultrasonic mode. The frequency targeting mode dynamically adjusts the size of the pulses in order to achieve a switching frequency within a desired band. The ultrasonic mode is switched into when the frequency of the pulses are at or below a threshold and the time of the pulses reaches a minimum threshold.
    Type: Grant
    Filed: March 2, 2011
    Date of Patent: September 3, 2013
    Assignee: Exar Corporation
    Inventors: Jason Weinstein, Zhenyu Zhao, Jingquan Chen
  • Patent number: 8526883
    Abstract: An RF switch for an RF splitter is disclosed, in which the bias voltage for the RF switching elements can be supplied, by using an RF to DC translator, from the RF signal on the input side to the switch. By using a native NMOS switch, routing of the RF signal is thus enabled without the necessity for an external power supply.
    Type: Grant
    Filed: June 11, 2009
    Date of Patent: September 3, 2013
    Assignee: NXP, B.V.
    Inventor: Frederic Francois Villain
  • 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: 8514596
    Abstract: The present invention includes: an inverter 1 configured to perform pulse wide modulation on an output from a DC power source 5; a first capacitor pair 41 provided at an input side of the inverter and including two capacitors serially connected to form a neutral point; a second capacitor pair 42 provided at an output side of the inverter and including two capacitors serially connected to form a neutral point; a bypass path g for a leakage current formed by connecting the neutral point of the first capacitor pair and the neutral point of the second capacitor pair to each other; at least one common mode choke coil 3 provided between the first capacitor pair and the second capacitor pair and configured to suppress a common mode current generated in the inverter; and an output filter 2 configured to convert a voltage, which is outputted from the inverter and subjected to the pulse wide modulation, into a voltage in a sine wave form.
    Type: Grant
    Filed: July 21, 2009
    Date of Patent: August 20, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yushi Koyama, Junichi Tsuda, Hiroshi Mochikawa
  • Patent number: 8513938
    Abstract: A reference voltage circuit includes a first amplifier, a first load device and a first PN junction device, second and third load devices and a second PN junction device, an offset voltage reduction circuit, a coupling node potential takeout circuit, and an area adjustment circuit. The offset voltage reduction circuit is configured to reduce an offset voltage between the first and second input terminals at the first amplifier, and the coupling node potential takeout circuit is configured to take out potentials of the first and second coupling nodes. The area adjustment circuit is configured to adjust an area of the second PN junction device in accordance with the potentials of the first and second coupling nodes which are taken out by the coupling node potential takeout circuit.
    Type: Grant
    Filed: December 11, 2011
    Date of Patent: August 20, 2013
    Assignee: Fujitsu Semiconductor Limited
    Inventors: Suguru Tachibana, Hiroyuki Matsunami, Yukinobu Tanida
  • Patent number: 8508195
    Abstract: A PFC converter that prevents and reduces switching losses by controlling ripple of inductor current and enables application for high power usage, includes a switching device that is turned off when an inductor current flowing through an inductor reaches a first threshold value, and turned on when the inductor current reaches a second threshold value. A switching control circuit sets a reference value of the inductor current using results from an input voltage detection circuit and an output voltage detection circuit. The first threshold value is produced by adding a predetermined value to the reference value, and the second threshold value is produced by subtracting the predetermined value from the reference value.
    Type: Grant
    Filed: February 28, 2012
    Date of Patent: August 13, 2013
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Yoshiyuki Uno
  • Patent number: 8508892
    Abstract: An integrated circuit (10) for use in a DC-DC converter is protected against damage from electrostatic discharge when not in use in the DC-DC converter. The integrated circuit includes a control circuit (11) and a switching transistor (12, 20) coupled between a first and second terminal (10a, b) of the integrated circuit (10). During DC-DC conversion the control circuit controls periodic switching of the switching transistor. The integrated circuit (10) furthermore comprises an electrostatic discharge (ESD) protection circuit, with a high pass filter circuit (160, 162) with inputs between terminals (10a, b) of the integrated circuit (10) and an output coupled to a detector transistor (164). The detector transistor (164) charges a chargeable circuit (17). From a node between the detector transistor (164) and the chargeable circuit (17) the switching transistor (12, 20) is made conductive when the detector transistor (164) becomes conductive.
    Type: Grant
    Filed: December 19, 2008
    Date of Patent: August 13, 2013
    Assignee: ST-Ericsson SA
    Inventors: Deepak Gajanana, Yorgos Christoforou
  • 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: 8508965
    Abstract: An inverter for converting a DC input voltage to an AC output voltage with an H-bridge is provided. A storage choke circuit is provided between the H-bridge and output-side AC voltage terminals. The storage choke circuit includes a freewheeling path with a freewheeling diode for commutating the current after a turn-off process of a semiconductor switch of the H-bridge. In this arrangement, each switching semiconductor switch is coupled to a resonant circuit which contains capacitive resonant elements and inductive resonant elements. The freewheeling path includes first and second freewheeling diodes connected in parallel, wherein the parallel circuit is connected in series with the inductive resonant elements and the second freewheeling diode is connected in series with capacitive freewheeling elements which are charged to a corresponding voltage at the start of a freewheeling phase as elements of the resonant circuit for zero voltage switching of the second freewheeling diode.
    Type: Grant
    Filed: May 18, 2009
    Date of Patent: August 13, 2013
    Assignee: Siemens Aktiengesellschaft
    Inventor: Jalal Hallak
  • Patent number: 8508962
    Abstract: A control circuit, during a positive period in which current flows from a power conversion apparatus to a load, causes a second snubber capacitor to discharge by controlling a second auxiliary switch to be turned on while a second main diode is turned on, and during a negative period in which current flows from the load to the power conversion apparatus, causes a first snubber capacitor to discharge by controlling a first auxiliary switch to be turned on while a first main diode is turned on.
    Type: Grant
    Filed: April 15, 2010
    Date of Patent: August 13, 2013
    Assignee: Toshiba Mitsubishi-Electric Industrial Systems Corporation
    Inventors: Yasuhiko Hosokawa, Toshifumi Ise, Hirotake Nakaji
  • Patent number: 8508957
    Abstract: A power conversion device includes an inverter for converting DC power to AC power to supply the AC power to a load, a converter for converting AC power from an AC power supply to DC power to supply the DC power to the inverter, a DC voltage converter for converting a voltage value of power stored in a storage battery to supply DC power from the storage battery to the inverter when power supply by the AC power supply is abnormal, and a filter which includes a reactor and a capacitor and removes harmonics generated by the inverter. The inverter includes a three-level circuit constituted of an arm and an AC switch.
    Type: Grant
    Filed: October 16, 2008
    Date of Patent: August 13, 2013
    Assignee: Toshiba Mitsubishi-Electric Industrial Systems Corporation
    Inventors: Kazuhide Eduardo Sato, Masahiro Kinoshita, Yushin Yamamoto, Tatsuaki Amboh
  • Patent number: 8503193
    Abstract: Power supplies, power adapters, and related methods are disclosed. One example power supply includes an open loop DC to DC converter having an input for connecting to an input power source and an output for supplying a DC output voltage or current and an enable/disable circuit coupled to the open loop DC to DC converter. The enable/disable circuit is configured to enable and disable the open loop DC to DC converter as a function of the DC output voltage or current. One example method includes determining a DC output voltage or current from an open loop DC to DC converter and enabling and disabling the open loop DC to DC converter as a function of the determined DC output voltage or current.
    Type: Grant
    Filed: August 26, 2010
    Date of Patent: August 6, 2013
    Assignee: Astec International Limited
    Inventor: Robert H. Kippley
  • Patent number: 8502510
    Abstract: The present technology discloses a switching mode power supply with predicted PWM control. In one embodiment, the switching mode power supply monitors the slew rate of COMP signal which represents the output voltage of the switching mode power supply. When the load steps up, the ON state of the power stage is prolonged; when the load steps down, the power stage is turned off earlier.
    Type: Grant
    Filed: January 28, 2011
    Date of Patent: August 6, 2013
    Assignee: Monolithic Power Systems, Inc.
    Inventors: Honggang Sheng, Chia-Hsin Chang
  • Patent number: 8502509
    Abstract: A power conversion system and power control method for reducing cross regulation effect uses a voltage feedback adjustment circuit to modulate an error signal fed back from an output voltage so as to predict the energy of an output corresponding to its load states. While the energy delivered to an output terminal with its load remaining the same does not change, the energy delivered to an output terminal with its load changing is adjusted accordingly. The power conversion system thus effectively reduces the cross regulation effect and obtains excellent steady system output and transient response.
    Type: Grant
    Filed: August 7, 2012
    Date of Patent: August 6, 2013
    Assignee: Alpha & Omega Semiconductor, Inc.
    Inventors: Jean-shin Wu, Ke-Horng Chen