Patents by Inventor Hengchun Mao

Hengchun Mao has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20160301348
    Abstract: A device comprises a motor/generator having an air gap and a plurality of windings, a plurality of power converter groups, and a control system. The windings are so configured that the number of phases in a pair of poles and the number of poles of the motor/generator can be dynamically adjusted. The power converter group comprises a plurality of power converters which is coupled between an input voltage source and a plurality of windings for controlling currents in the windings. The control system is so configured such that the number of poles of the motor/generator and the number of phases in a pair of poles are dynamically adjusted, and a synchronous speed of a moving magnetic field generated by winding currents within first pair of poles is approximately equal to a synchronous speed of a second moving magnetic field generated by currents in the windings within second pair of poles.
    Type: Application
    Filed: April 9, 2016
    Publication date: October 13, 2016
    Applicant: Powerest LLC
    Inventors: Hengchun Mao, Xuezhong Jia
  • Patent number: 9467057
    Abstract: A multilevel LLC resonant converter comprises a resonant tank connected in series with a primary side of a transformer, a first switch and a second switch connected in series, wherein a common node of the first switch and the second switch is coupled to a mid-voltage point through a first isolation switch and the resonant bank and a third switch and a fourth switch connected in series, wherein a common node of the third switch and the fourth switch is coupled to the resonant tank.
    Type: Grant
    Filed: May 28, 2015
    Date of Patent: October 11, 2016
    Assignee: Futurewei Technologies, Inc.
    Inventors: Dianbo Fu, Wensong Yu, Hengchun Mao, Heping Dai
  • Patent number: 9436192
    Abstract: A converter comprises a high side switch, a low side switch connected in series with the high switch, a gate drive circuit comprising a first drive port coupled to a gate of the high side switch, a second drive port coupled to a gate of the low side switch, an SRE input port and a PWM input port coupled to a PWM controller, wherein the PWM controller is selected from the group consisting of a first PWM controller having two complementary PWM outputs, a second PWM controller having a tri-state PWM output and a third PWM controller having a single PWM output.
    Type: Grant
    Filed: August 1, 2013
    Date of Patent: September 6, 2016
    Assignee: FUTUREWEI TECHNOLOGIES, INC.
    Inventors: Heping Dai, Hengchun Mao, Zhihua Liu, Zhaozheng Hou
  • Publication number: 20160254751
    Abstract: A power regulator comprises a first power switch configured to carry a pulsed current, an input capacitor between a positive terminal of an input voltage bus and a return point, an output capacitor between a positive terminal of an output voltage bus and the return point and a protection device coupled between the return point and a common return point of the input voltage bus and the output voltage bus, wherein the pulsed current is configured to flow through the protection device.
    Type: Application
    Filed: May 9, 2016
    Publication date: September 1, 2016
    Inventors: Hengchun Mao, Yan-Fei Liu, Renhua Wu
  • Patent number: 9344042
    Abstract: A device comprises a switch network having a plurality of switch cells connected in series, an output voltage at an output voltage port with an output capacitor, and an impedance network coupled between the switch network and an output voltage port with an output capacitor. Each switch cell has a plurality of input voltages and a plurality of switches, in which each switch is coupled to an input voltage, and a first input voltage coupled to a first switch has a different value from a second input voltage coupled to a second switch. The output voltage is configured to be a combination of the input voltages of the switch network in the form of: Vo=?1NKi×Vi, where Vo is the output voltage, N is the number of input voltages, Vi is the ith input voltage, and Ki is an integer equal to 0 or 1 depending on the ON/OFF status of the switches in the switch network.
    Type: Grant
    Filed: February 20, 2014
    Date of Patent: May 17, 2016
    Inventor: Hengchun Mao
  • Patent number: 9337641
    Abstract: An embodiment high efficiency power regulator comprises a three-terminal converter and a protection device. The three-terminal converter comprises a first terminal coupled to a positive terminal of an input voltage bus, a second terminal coupled to a positive terminal of an output voltage bus and a third terminal coupled to the protection device. The protection device comprises an inrush current limiting element connected in series with a reverse polarity protection device.
    Type: Grant
    Filed: April 15, 2014
    Date of Patent: May 10, 2016
    Assignee: Futurewei Technologies, Inc.
    Inventors: Hengchun Mao, Yan-Fei Liu, Renhua Wu
  • Publication number: 20160056639
    Abstract: A system comprises a primary switch network coupled to a power source, wherein the primary switch network comprises a plurality of power switches, a primary resonant tank coupled to the plurality of power switches, wherein a resonant capacitor of the primary resonant tank is formed by a first variable capacitance network, and wherein the first variable capacitance network is modulated to improve soft switching of the plurality of power switches through reducing a voltage level and a current level of a switch at a turn-on instant and a primary coil coupled to the primary resonant tank.
    Type: Application
    Filed: August 24, 2015
    Publication date: February 25, 2016
    Inventor: Hengchun Mao
  • Publication number: 20160056747
    Abstract: An electrical machine comprises a rotor, and a stator magnetically coupled to the rotor and having a plurality of slots and a plurality of windings, wherein each winding is installed in two corresponding slots, a plurality of magnetic poles and a plurality of phases in each pair of poles are formed when currents flow through the windings, and the windings are so configured that the number of phases and the number of poles can be dynamically adjusted.
    Type: Application
    Filed: August 24, 2014
    Publication date: February 25, 2016
    Inventor: Hengchun Mao
  • Publication number: 20160056640
    Abstract: A power converter comprises a primary switch network coupled to a power source, wherein the primary switch network comprises a plurality of power switches, a controller configured to generate gate drive signals for the plurality of power switches, a secondary rectifier coupled to an output, a first transformer having a first winding coupled to the primary switch network, a second winding coupled to the secondary rectifier and a third winding coupled to the controller and a second transformer having a fourth winding coupled to the primary switch network, a fifth winding coupled to the secondary rectifier and a sixth winding coupled to the controller, wherein a voltage signal from the third winding and/or the sixth winding is processed to provide a feedback of a voltage at the output.
    Type: Application
    Filed: August 25, 2015
    Publication date: February 25, 2016
    Inventor: Hengchun Mao
  • Patent number: 9240748
    Abstract: An electrical machine comprises a rotor, and a stator magnetically coupled to the rotor. The stator has a plurality of slots and a plurality of windings, and each winding is installed in a corresponding slot. A plurality of magnetic poles and a plurality of phases in each pair of poles are formed when currents flow through the windings. The windings are so configured that the number of phases and the number of poles can be dynamically adjusted.
    Type: Grant
    Filed: February 20, 2014
    Date of Patent: January 19, 2016
    Inventor: Hengchun Mao
  • Patent number: 9190911
    Abstract: A resonant tank comprises a series resonant inductor coupled to a switching network and a transformer, a series resonant capacitor coupled to the switching network and the transformer, a first parallel inductor implemented as a magnetizing inductance of the transformer, a second parallel inductor implement as a separate inductor, wherein a first inductance of the first parallel inductor is greater than a second inductance of the second parallel inductor and a switch connected in series with the second parallel inductor.
    Type: Grant
    Filed: March 5, 2013
    Date of Patent: November 17, 2015
    Assignee: Futurewei Technologies, Inc.
    Inventors: Heping Dai, Hengchun Mao, Dianbo Fu
  • Patent number: 9178438
    Abstract: A converter comprises a bridge and a resonant tank coupled between the bridge and an isolation transformer. The converter is configured such that the converter operates at a first constant-gain resonant frequency during a normal operation condition wherein a voltage gain of the converter is essentially insensitive to an output load change and the converter operates at a minimum-gain damping frequency during an abnormal operation condition wherein a voltage gain of the converter is approximately equal to zero.
    Type: Grant
    Filed: April 5, 2013
    Date of Patent: November 3, 2015
    Assignee: Futurewei Technologies, Inc.
    Inventors: Dianbo Fu, Hengchun Mao, Heping Dai
  • Publication number: 20150263626
    Abstract: An embodiment power converter package comprises a semiconductor die, an output inductor, a plurality of input capacitors and output capacitors. The semiconductor die, the output inductor and the plurality of capacitors are mounted on a lead frame and connected one to another through various pads on the lead frame. The semiconductor die comprises a high side switch, a low side switch and a driver. The power converter package is electrically coupled to an external pulse width modulation controller through a variety of input and output pads.
    Type: Application
    Filed: June 2, 2015
    Publication date: September 17, 2015
    Inventors: Hengchun Mao, Dianbo Fu, Bing Cai
  • Publication number: 20150263635
    Abstract: A multilevel LLC resonant converter comprises a resonant tank connected in series with a primary side of a transformer, a first switch and a second switch connected in series, wherein a common node of the first switch and the second switch is coupled to a mid-voltage point through a first isolation switch and the resonant bank and a third switch and a fourth switch connected in series, wherein a common node of the third switch and the fourth switch is coupled to the resonant tank.
    Type: Application
    Filed: May 28, 2015
    Publication date: September 17, 2015
    Inventors: Dianbo Fu, Wensong Yu, Hengchun Mao, Heping Dai
  • Patent number: 9122287
    Abstract: Dual frequency control of first and second pairs of switches of a buck-boost regulator with pass through band is disclosed. In buck and boost modes respectively a first pair of the switches is operated at high frequency and a second pair of the switches is operated at low frequency. In pass through mode, both pairs of switches are operated at low frequency. Dual frequency control and operation of the pairs of switches enables current sharing between positive and negative power leads in buck, boost and pass-through modes.
    Type: Grant
    Filed: May 25, 2012
    Date of Patent: September 1, 2015
    Assignee: Futurewei Technologies, Inc.
    Inventors: Hengchun Mao, Yan-Fei Liu
  • Patent number: 9088215
    Abstract: An embodiment power converter package comprises a semiconductor die, an output inductor, a plurality of input capacitors and output capacitors. The semiconductor die, the output inductor and the plurality of capacitors are mounted on a lead frame and connected one to another through various pads on the lead frame. The semiconductor die comprises a high side switch, a low side switch and a driver. The power converter package is electrically coupled to an external pulse width modulation controller through a variety of input and output pads.
    Type: Grant
    Filed: June 8, 2011
    Date of Patent: July 21, 2015
    Assignee: Futurewei Technologies, Inc.
    Inventors: Hengchun Mao, Dianbo Fu, Bing Cai
  • Publication number: 20150194811
    Abstract: A device comprises a switch network coupled to a power source, wherein the switch network comprises a plurality of power switches, a transmitter resonant tank coupled to the plurality of power switches, wherein the transmitter resonant tank comprises a primary resonant capacitor, a transmitter coil coupled to the transmitter resonant tank and a harmonic reduction apparatus coupled between the switch network and the transmitter coil, wherein the harmonic reduction apparatus is configured to attenuate at least one undesired frequency component.
    Type: Application
    Filed: January 6, 2015
    Publication date: July 9, 2015
    Inventor: Hengchun Mao
  • Patent number: 9077255
    Abstract: A multilevel LLC resonant converter comprises a resonant tank connected in series with a primary side of a transformer, a first switch and a second switch connected in series, wherein a common node of the first switch and the second switch is coupled to a mid-voltage point through a first isolation switch and the resonant bank and a third switch and a fourth switch connected in series, wherein a common node of the third switch and the fourth switch is coupled to the resonant tank.
    Type: Grant
    Filed: January 11, 2013
    Date of Patent: July 7, 2015
    Assignee: Futurewei Technologies, Inc.
    Inventors: Dianbo Fu, Wensong Yu, Hengchun Mao, Heping Dai
  • Patent number: 8970067
    Abstract: An embodiment hybrid dc/dc converter comprises a first power source and a low power converter coupled to the first power source. The low power converter generates an output connected in series with the first power source. The hybrid dc/dc converter further comprises a selection network coupled to the first power source and the output of the low power converter and a main unregulated power converter coupled to the selection network. By controlling the voltage across the output of the low power converter, the hybrid dc/dc converter can achieve high efficiency through the unregulated power converter.
    Type: Grant
    Filed: November 30, 2011
    Date of Patent: March 3, 2015
    Assignee: Futurewei Technologies, Inc.
    Inventors: Dianbo Fu, Hengchun Mao, Bing Cai
  • Patent number: 8957644
    Abstract: A power system comprising a non-isolated voltage regulator configured to couple to an input voltage and produce an output voltage, wherein the non-isolated voltage regulator is in a power distribution system and configured to boost the input voltage when the input voltage is less than a minimum output voltage, to reduce the input voltage when the input voltage is greater than a maximum output voltage, and to pass-through the input voltage when the input voltage is greater than or equal to the minimum output voltage and less than or equal to the maximum output voltage.
    Type: Grant
    Filed: December 20, 2010
    Date of Patent: February 17, 2015
    Assignee: Futurewei Technologies, Inc.
    Inventors: Hengchun Mao, Dianbo Fu, Bing Cai