Patents by Inventor Saijun Mao

Saijun 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).

  • Patent number: 11555380
    Abstract: A downhole power generation includes a power generation module for providing power to a load. A turbine is driven by flow of a downhole fluid to rotate. A generator is coupled with the turbine for converting rotational energy from the turbine to electrical energy, and an AC-DC rectifier is coupled with the generator for converting an alternating voltage from the generator to a direct voltage. A power conversion circuit couples the AC-DC rectifier with the load. The power conversion circuit is configured for providing a first power to the load when the load is in a working mode and providing a second power to the load when the load is in a non-working mode. The second power is less than the first power. A downhole power generation method is also disclosed.
    Type: Grant
    Filed: April 24, 2018
    Date of Patent: January 17, 2023
    Assignee: BAKER HUGHES, A GE COMPANY, LLC
    Inventors: Saijun Mao, Yunzheng Chen, Yi Liao, Xuele Qi, Ming Xue, Stewart Blake Brazil
  • Patent number: 11454094
    Abstract: A downhole power generation system is disclosed, which includes a turbine generator system. The turbine generator system includes a turbine, a generator coupled with the turbine and having an AC-DC rectifier, and an optimized power control unit. The turbine is driven by flow of a downhole fluid to rotate. The generator converts rotational energy from the turbine to electrical energy and outputting a direct current voltage. The turbine generator system is coupled to a load via the optimized power control unit. The optimized power control unit controls to regulate an output voltage of the generator and provides a regulated output voltage to the load so that the turbine generator system has an optimized power output. An optimized power control method for a downhole power generation system is also disclosed.
    Type: Grant
    Filed: April 24, 2018
    Date of Patent: September 27, 2022
    Assignee: BAKER HUGHES, A GE COMPANY, LLC
    Inventors: Yunzheng Chen, Yi Liao, Saijun Mao, Ming Xue, Stewart Blake Brazil, Xuele Qi
  • Publication number: 20210102444
    Abstract: A downhole power generation system is disclosed, which includes a turbine generator system. The turbine generator system includes a turbine, a generator coupled with the turbine and having an AC-DC rectifier, and an optimized power control unit. The turbine is driven by flow of a downhole fluid to rotate. The generator converts rotational energy from the turbine to electrical energy and outputting a direct current voltage. The turbine generator system is coupled to a load via the optimized power control unit. The optimized power control unit controls to regulate an output voltage of the generator and provides a regulated output voltage to the load so that the turbine generator system has an optimized power output. An optimized power control method for a downhole power generation system is also disclosed.
    Type: Application
    Filed: April 24, 2018
    Publication date: April 8, 2021
    Inventors: Yunzheng CHEN, Yi LIAO, Saijun MAO, Ming XUE, Stewart Blake BRAZIL, Xuele QI
  • Patent number: 10862402
    Abstract: According to various embodiments, a system and method for a power converter including an inverter and a first voltage multiplier is disclosed. The inverter is configured to convert a first DC voltage into a first AC voltage. The first voltage multiplier is coupled to an output of the inverter and configured to convert the first AC voltage into a second DC voltage higher than a peak value of the first AC voltage. The first voltage multiplier includes a plurality of stages, each stage including two diodes, and each diode in a first stage of the plurality of stages including at least one of a silicon carbide diode and a gallium nitride diode.
    Type: Grant
    Filed: January 2, 2019
    Date of Patent: December 8, 2020
    Assignee: GENERAL ELECTRIC COMPANY
    Inventor: Saijun Mao
  • Publication number: 20200056458
    Abstract: A downhole power generation system is disclosed, which includes a power generation module for providing power to a load, comprising a turbine driven by flow of a downhole fluid to rotate, a generator coupled with the turbine for converting rotational energy from the turbine to electrical energy, and an AC-DC rectifier coupled with the generator for converting an alternating current voltage from the generator to a direct current voltage, and a power conversion circuit coupling the AC-DC rectifier with the load. The power conversion circuit is configured for providing a first power to the load when the load is in a working mode and providing a second power to the load when the load is in a non-working mode. The second power is less than the first power. A downhole power generation method is also disclosed.
    Type: Application
    Filed: April 24, 2018
    Publication date: February 20, 2020
    Inventors: Saijun MAO, Yunzheng CHEN, Yi LIAO, Xuele QI, Ming XUE, Stewart Blake BRAZIL
  • Publication number: 20190372474
    Abstract: An energy converting device comprises an energy converting circuit which is provided on a substrate and configured to convert an input direct voltage into an output direct voltage higher than the input direct voltage, wherein the substrate comprises a first layer and a second layer. The energy converting circuit comprises a plurality of semiconductor devices and a planar transformer. Each of the semiconductor devices is in a flat shape and mounted on the substrate. The planar transformer comprises a primary circuit arranged on the first layer and a secondary circuit arranged on the second layer. The secondary circuit is insulated from the primary circuit by an insulation layer between the first and second layers.
    Type: Application
    Filed: February 23, 2018
    Publication date: December 5, 2019
    Inventors: Saijun MAO, Stewart Blake BRAZIL
  • Patent number: 10497642
    Abstract: The present disclosure relates to an integrated power semiconductor packaging apparatus and a power converter containing the integrated power semiconductor packaging apparatus. The integrated power semiconductor packaging apparatus comprises a plurality of power semiconductor devices and an electrically insulative substrate formed integrally. The electrically insulative substrate comprises a flat surface, at least one separation wall protruding from the flat surface and a flow channel inside the electrically insulative substrate. The at least one separation wall is configured to separate the flat surface into a plurality of flat areas, and each of the plurality of flat areas is configured to receive one of the plurality of power semiconductor devices. The flow channel is configured for allowing a coolant flowing through to remove heat from the plurality of power semiconductor devices.
    Type: Grant
    Filed: May 17, 2018
    Date of Patent: December 3, 2019
    Assignee: General Electric Company
    Inventors: Saijun Mao, Bo Qu, Jingkui Shi, He Xu, Jie Shen, Lin Lan, Rui Li, Zhihui Yuan, Alistair Martin Waddell, Stefan Schroeder, Marius Michael Mechlinski, Mark Aaron Chan
  • Patent number: 10389230
    Abstract: The present disclosure relates to a snubber circuit which comprises a static snubber unit, connected in parallel with the switch, for balancing a static voltage sharing across a switch when the switch is in a state of turn-on or turn-off; and a dynamic snubber unit for balance a dynamic voltage sharing across the switch when the switch is in a process of turn-on or turn-off, comprising a dynamic voltage sharing capacitor connected in parallel with the switch and having a relationship between a capacitance and a voltage of the dynamic voltage sharing capacitor; and a controller for controlling the capacitance of the dynamic voltage sharing capacitor to be in a predetermined working area of capacitance rising while the voltage across the switch is increasing. The present disclosure also relates to a power semiconductor device.
    Type: Grant
    Filed: February 23, 2018
    Date of Patent: August 20, 2019
    Assignee: GENERAL ELECTRIC COMPANY
    Inventors: Saijun Mao, Stefan Schroeder, Jingkui Shi, He Xu, Marius Michael Mechlinski, Bo Qu, Zhihui Yuan, Yingqi Zhang, Jie Shen
  • Publication number: 20190245426
    Abstract: A power converter comprising an inverter and a first voltage multiplier. The inverter is configured to convert a first DC voltage into a first AC voltage. The first voltage multiplier is coupled with an output of the inverter and configured to convert the first AC voltage into a second DC voltage higher than a peak value of the first AC voltage. The first voltage multiplier comprises a plurality of stages, wherein the first voltage step is closer to the input of the first voltage multiplier than the other voltage steps in terms of energy transmission, each stage comprising two diodes, and each diode in a first stage of the plurality of stages comprises at least one of a silicon carbide diode and a gallium nitride diode. Embodiments of the present invention also relate to a power converting method.
    Type: Application
    Filed: January 2, 2019
    Publication date: August 8, 2019
    Inventor: Saijun Mao
  • Publication number: 20190131055
    Abstract: An isolation transformer, comprising: a primary winding printed on a first substrate; a shorted winding printed on a second substrate; and a secondary winding printed on a third substrate. The shorted winding is magnetically coupled to the primary winding; the secondary winding is magnetically coupled with the shorted winding. Embodiments of the present invention also relate to a switch driving circuit and a pulse power system.
    Type: Application
    Filed: October 9, 2018
    Publication date: May 2, 2019
    Inventor: Saijun MAO
  • Publication number: 20190089350
    Abstract: The present disclosure relates to a method for controlling voltage balance of a serialized power switching device, comprising generating a reference voltage based on actual individual voltage of each switch of the serialized power switching device or setting a reference voltage based on supplied voltage to the serialized power switching device; determining an individual blocking voltage mismatch of at least one switch when existing a difference between the reference voltage and the actual individual voltage of at least one switch, wherein the individual voltage mismatch is based on the difference between the reference voltage and the actual individual voltage; calculating an individual delay mismatch for the at least one switch; and compensating the individual delay mismatch for the at least one switch. The present disclosure also relates to a system for controlling voltage balance of a serialized power switching device. The present disclosure also relates to a power switching device.
    Type: Application
    Filed: August 31, 2018
    Publication date: March 21, 2019
    Inventors: Bo QU, Ying ZHANG, Marius Michael MECHLINSKI, Saijun MAO, Jingkui SHI, He XU, Zhihui YUAN, Jie SHEN, Stefan SCHROEDER
  • Patent number: 10187056
    Abstract: A direct current (DC) circuit breaker for power transmission or distribution system includes a current sensor for sensing current of a system, a controller, a physical switch, and multiple switch modules. The multiple switch modules are electrically coupled to the current sensor and the physical switch in series. Each switch module includes multiple base elements electrically coupled in parallel. Each base element includes a first silicon carbide (SiC) metal-oxide-semiconductor field-effect transistor (MOSFET) and a second SiC MOSFET electrically coupled in an opposite series connection mode. The first and second SiC MOSFETs are configured in a synchronous rectification mode by channel reverse conduction control. The controller controls the multiple switch modules to connect current in the system, and break current of the multiple switch modules according to sensed current signals from the current sensor.
    Type: Grant
    Filed: May 21, 2014
    Date of Patent: January 22, 2019
    Assignee: GE ENERGY POWER CONVERSION TECHNOLOGY LIMITED
    Inventors: Pengju Kang, Saijun Mao, Fei Xu, Wenqiang Yang, Yingqi Zhang, Pengcheng Zhu
  • Publication number: 20180342349
    Abstract: An integrated system for signal and power transmission with galvanic isolation is disclosed. The integrated system comprises an insulative layer having a primary side and a secondary side; a planar signal transformer and a planar power transformer for signal and power transmission between the primary and the secondary sides of the insulative layer respectively. The planar signal transformer comprises two signal coupling elements which are disposed on the primary and the secondary sides of the insulative layer respectively. The planar power transformer includes two power coupling elements which are disposed on the primary and the secondary sides of the insulative layer respectively. Each of the two signal coupling elements and the two power coupling elements is embedded in at least one layer of a multi-layer printed circuit board. The integrated system of the present disclosure has a compact structure and is suitable for automatic assembly and manufacturing.
    Type: Application
    Filed: May 23, 2018
    Publication date: November 29, 2018
    Inventors: Saijun Mao, Bo Qu, Jingkui Shi, He Xu, Jie Shen, Tingting Song, Zhihui Yuan, Xin Jiang, Xi Lu, Stefan Schroeder, Marius Michael Mechlinski
  • Publication number: 20180337109
    Abstract: The present disclosure relates to an integrated power semiconductor packaging apparatus and a power converter containing the integrated power semiconductor packaging apparatus. The integrated power semiconductor packaging apparatus comprises a plurality of power semiconductor devices and an electrically insulative substrate formed integrally. The electrically insulative substrate comprises a flat surface, at least one separation wall protruding from the flat surface and a flow channel inside the electrically insulative substrate. The at least one separation wall is configured to separate the flat surface into a plurality of flat areas, and each of the plurality of flat areas is configured to receive one of the plurality of power semiconductor devices. The flow channel is configured for allowing a coolant flowing through to remove heat from the plurality of power semiconductor devices.
    Type: Application
    Filed: May 17, 2018
    Publication date: November 22, 2018
    Inventors: Saijun MAO, Bo QU, Jingkui SHI, He XU, Jie SHEN, Lin LAN, Rui LI, Zhihui YUAN, Alistair Martin WADDELL, Stefan SCHROEDER, Marius Michael MECHLINSKI, Mark Aaron CHAN
  • Publication number: 20180287487
    Abstract: The present disclosure relates to a snubber circuit which comprises a static snubber unit, connected in parallel with the switch, for balancing a static voltage sharing across a switch when the switch is in a state of turn-on or turn-off; and a dynamic snubber unit for balance a dynamic voltage sharing across the switch when the switch is in a process of turn-on or turn-off, comprising a dynamic voltage sharing capacitor connected in parallel with the switch and having a relationship between a capacitance and a voltage of the dynamic voltage sharing capacitor; and a controller for controlling the capacitance of the dynamic voltage sharing capacitor to be in a predetermined working area of capacitance rising while the voltage across the switch is increasing. The present disclosure also relates to a power semiconductor device.
    Type: Application
    Filed: February 23, 2018
    Publication date: October 4, 2018
    Inventors: Saijun Mao, Stefan Schroeder, Jingkui Shi, He Xu, Marius Michael Mechlinski, Bo Qu, Zhihui Yuan, Yingqi Zhang, Jie Shen
  • Patent number: 9537423
    Abstract: A power conversion system includes a filter unit, a DC/DC converter, a DC link, an inverter, a control unit, and a traction motor. The DC/DC converter is used for boosting DC voltage of a DC source and electrically coupled to the DC source through the filter unit. The DC/DC converter includes multiple SiC MOSFETs configured in a synchronous rectification mode by channel reverse conduction control. The inverter is used for converting the boosted DC voltage from the converter to multi-phase AC voltage through the DC link. The control unit is used for providing PWM commands to the converter and the inverter, to convert the DC voltage to AC voltage configured to drive an AC driven device.
    Type: Grant
    Filed: September 19, 2013
    Date of Patent: January 3, 2017
    Assignee: GENERAL ELECTRIC COMPANY
    Inventor: Saijun Mao
  • Patent number: 9516723
    Abstract: A system having an alternating current (AC) driven LED unit, an AC voltage regulator, and a controller is provided. The AC driven LED unit includes a first LED and a second LED coupled in reverse parallel. The AC voltage regulator is operable to receive AC voltage originating from an AC voltage source, regulate the AC voltage according to control signals from the controller, and apply regulated AC voltage to the AC driven LED unit, so as to enable the first LED and the second LED to emit light according to the regulated AC voltage. In addition, a method is provided for driving the LED by regulating the AC voltage. By regulating the AC voltage using the AC voltage regulator, benefits of restraining voltage fluctuations, reducing THD, improving power factor, providing dimming control, and mitigating flicker phenomenon can be achieved.
    Type: Grant
    Filed: June 14, 2011
    Date of Patent: December 6, 2016
    Assignee: GENERAL ELECTRIC COMPANY
    Inventors: Saijun Mao, Yunfeng Liu, Xiaoming Yuan, Yingqi Zhang, Charles Adrian Becker, Junhui Fei, Jian Wang
  • Patent number: 9455580
    Abstract: A battery system has a battery module including a number M of series-connected batteries. The battery system is further provided with a number N (1<N?M) of charge equalizers, each of which once connected to a battery, causes the battery to be charged and/or discharged to achieve charge equalization. A control device is configured to determine for each battery if it requires charge equalization based on a state of charge (SOC) of the battery, compare a number L of the batteries that require charge equalization and the number M, and based on the comparison result, cause the battery system to be shut down, or the one or more batteries that require charge equalization to be connected to corresponding charge equalizers. A selective switch module is used for connecting the one or more batteries that require charge equalization to corresponding charge equalizers, respectively.
    Type: Grant
    Filed: July 2, 2014
    Date of Patent: September 27, 2016
    Assignee: GENERAL ELECTRIC COMPANY
    Inventors: Saijun Mao, Huiqing Wu, Herman Lucas Norbert Wiegman, Qunjian Huang, Ying Mei
  • Publication number: 20160262250
    Abstract: A power generation system includes an input to receive a low-voltage alternating current and a number N of voltage-conversion modules coupled to the input, each electrically connected in series. Each voltage-conversion module includes a transformer configured to convert the low-voltage alternating current into a high voltage alternating current. Each voltage-conversion module includes a multiplier configured to convert the high-voltage alternating current from the transformer into a high-voltage direct current. The multiplier includes a positive multiplier part and a negative multiplier part. The positive multiplier part and the negative multiplier part each includes a. pair of input terminals connected in parallel with the transform and at least one multiplier stage comprising a single diode and a capacitor assembly. The number N is an even number between 4 and 24.
    Type: Application
    Filed: May 17, 2016
    Publication date: September 8, 2016
    Inventors: Saijun MAO, Denis Perrillat-Amede, Philippe Ernest, Niranjan Kumar, Xu Chu
  • Patent number: 9369060
    Abstract: A power generation system includes an input to receive a low-voltage alternating current and a number N of voltage-conversion modules coupled to the input, each electrically connected in series. Each voltage-conversion module includes a transformer configured to convert the low-voltage alternating current into a high-voltage alternating current. Each voltage-conversion module includes a multiplier configured to convert the high-voltage alternating current from the transformer into a high-voltage direct current. The multiplier includes a positive multiplier part and a negative multiplier part. The positive multiplier part and the negative multiplier part each includes a pair of input terminals connected in parallel with the transform and at least one multiplier stage comprising a single diode and a capacitor assembly. The number N is an even number between 4 and 24.
    Type: Grant
    Filed: January 4, 2013
    Date of Patent: June 14, 2016
    Assignee: GENERAL ELECTRIC COMPANY
    Inventors: Saijun Mao, Denis Perrillat-Amede, Philippe Ernest, Niranjan Kumar, Xu Chu