Patents by Inventor Lixiang Wei

Lixiang Wei 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).

  • Method and apparatus for bypassing Cascaded H-Bridge (CHB) power cells and power sub cell for multilevel inverter
    Patent number: 9007787
    Abstract: Bypassing methods and apparatus are presented along with power cells and sub cells for multilevel inverters in which DC current flow into a DC link capacitance is interrupted and a bypass switch is closed across a power cell or sub cell output to selectively bypass a power stage of a multilevel inverter.
    Type: Grant
    Filed: August 13, 2012
    Date of Patent: April 14, 2015
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Navid Zargari, Yuan Xiao, Lixiang Wei
  • APPARATUS AND METHOD FOR AUTOMATIC GROUND FAULT LOCATION DETERMINATION IN HIGH RESISTANCE GROUNDED MOTOR DRIVE SYSTEM
    Publication number: 20150097571
    Abstract: A PLC or other industrial controller programmed to locate ground faults in a networked high resistance grounded multi-drive system through network communications messaging to automatically place networked motor drives in various operational states to isolate individual drives for ground fault identification testing and selectively identify individual drives as suspected ground fault locations.
    Type: Application
    Filed: October 8, 2013
    Publication date: April 9, 2015
    Applicant: ROCKWELL AUTOMATION TECHNOLOGIES, INC.
    Inventors: Lixiang Wei, Jeffrey D. McGuire, Jiangang Hu, Zhijun Liu
  • MULTIFUNCTION POWER CONVERTER WITH OPTION FOR INTEGRATED MAGNETICS
    Publication number: 20150098257
    Abstract: Power converter modules and parallel conversion systems are presented in which the modules are provided in a rollable enclosure having AC and DC electrical connections, and an interior including a switching circuit with switching devices individually connected between a corresponding AC node and a corresponding DC node for operation as either a rectifier or an inverter and an internal filter circuit with inductors individually connected between a corresponding AC node of the switching circuit and a corresponding AC electrical connection, with a built-in blower or fan to cool the filter circuit during operation.
    Type: Application
    Filed: October 9, 2013
    Publication date: April 9, 2015
    Applicant: ROCKWELL AUTOMATION TECHNOLOGIES, INC.
    Inventors: Lixiang Wei, Robert M. Michalski, Yogesh Patel, Bruce W. Weiss, Brian P. Brown
  • HRG GROUND FAULT DETECTOR AND METHOD
    Publication number: 20150091582
    Abstract: A HRG ground fault detector and method for detecting a ground fault in a High Resistance Ground (HRG) system are provided. The HRG ground fault detector in one example embodiment includes a first input A coupled to a first phase PHA of the HRG system, a second input B coupled to a second phase PHB, and a third input C coupled to a third phase PHC, with the HRG ground fault detector generating a simulated neutral voltage VN? from the first phase PHA, the second phase PHB, and the third phase PHC, wherein the simulated neutral voltage VN? comprises a zero voltage potential when the first phase PHA, the second phase PHB, and the third phase PHC are equal, comparing the simulated neutral voltage VN? to a predetermined fault voltage threshold, and detecting a HRG ground fault if the simulated neutral voltage VN? exceeds the threshold.
    Type: Application
    Filed: October 1, 2013
    Publication date: April 2, 2015
    Applicant: ROCKWELL AUTOMATION TECHNOLOGIES, INC.
    Inventors: Lixiang Wei, Jiangang Hu, Jeffrey D. McGuire
  • Single phase operation of a three-phase drive system
    Patent number: 8988026
    Abstract: Single-phase voltage operation techniques are provided for a three-phase drive system. A drive system may include a rectifier configured to couple to a three-phase AC voltage source. The rectifier may be configured to convert AC voltage from the three-phase AC voltage source to a direct current (DC) voltage. The drive system may also include a controller configured to send a plurality of switching signals to a plurality of switches in the rectifier such that the plurality of switching signals minimizes a current provided to the rectifier when only a single-phase of the three-phase AC voltage source is available.
    Type: Grant
    Filed: July 31, 2012
    Date of Patent: March 24, 2015
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Ahmed Mohamed Sayed Ahmed, Lixiang Wei, Brian J. Seibel
  • AC pre-charge circuit
    Patent number: 8953296
    Abstract: AC pre-charging techniques are provided for pre-charging the DC bus on a motor drive. AC pre-charging techniques involve pre-charge circuitry including a manual switch, an automatic switch, and pre-charge control circuitry to switch the automatic switch between pre-charge and pre-charge bypass modes in response to an initialized pre-charge operation, input voltage sags, etc. In some embodiments, the pre-charge operation may be initialized by switching the manual switch closed. In some embodiments, the pre-charge operation may also be initialized by a detected voltage sag on the DC bus. The pre-charge circuitry may also be configured to disconnect a motor drive from the AC power supply under certain fault conditions.
    Type: Grant
    Filed: July 13, 2012
    Date of Patent: February 10, 2015
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Bruce W. Weiss, Doyle F. Busse, Jeremy J. Keegan, Lixiang Wei, Michael W. Loth, Rangarajan M. Tallam, Yogesh Patel
  • GROUND SCHEME IDENTIFICATION METHOD
    Publication number: 20150009726
    Abstract: The present techniques include methods and systems for detecting the grounding condition of an electrical system to automatically determine a suitable electrical drive configuration. The drive includes a test resistor which may be connected or disconnected from the drive to measure different drive voltages. The measured drive voltages are analyzed to determine a type of grounding configuration of the electrical system in which the drive is to be installed. Embodiments also include determining ground resistance condition such as a high resistance ground (HRG) fault or a ground resistance fault when the drive is in operation.
    Type: Application
    Filed: September 22, 2014
    Publication date: January 8, 2015
    Inventors: Lixiang Wei, David W. Kirschnik, Richard A. Lukaszewski, Gary L. Skibinski
  • Method of fabricating a choke assembly
    Patent number: 8910372
    Abstract: An improved choke assembly for a power electronics device is provided. More specifically, a choke assembly with improved protection from environmental conditions such as dirt and water is provided. An improved choke assembly may include an insulative housing for an inductor coil that seals the inductor coil from the environment.
    Type: Grant
    Filed: February 23, 2012
    Date of Patent: December 16, 2014
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: John R. Brubaker, Lixiang Wei
  • Ground scheme identification method
    Patent number: 8841917
    Abstract: The present techniques include methods and systems for detecting the grounding condition of an electrical system to automatically determine a suitable electrical drive configuration. The drive includes a test resistor which may be connected or disconnected from the drive to measure different drive voltages. The measured drive voltages are analyzed to determine a type of grounding configuration of the electrical system in which the drive is to be installed. Embodiments also include determining ground resistance condition such as a high resistance ground (HRG) fault or a ground resistance fault when the drive is in operation.
    Type: Grant
    Filed: March 31, 2011
    Date of Patent: September 23, 2014
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Lixiang Wei, David W. Kirschnik, Richard A. Lukaszewski, Gary L. Skibinski
  • METHOD AND APPARATUS FOR ISLANDING DETECTION FOR GRID TIE CONVERTERS
    Publication number: 20140265596
    Abstract: Methods and apparatus are presented for unintentional islanding detection for grid tie converters in which the phase angle disturbance is introduced by modification of grid side converter switching control signals and a mismatch of reactive power between generation and the grid load is formed upon the occurrence of unintentional islanding, where the applied phase disturbance is determined according to two pre-defined curves to form an equivalent positive feedback at different frequencies to prevent the converter from forming an island at a new stable frequency after the grid is disconnected.
    Type: Application
    Filed: March 14, 2013
    Publication date: September 18, 2014
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: Zhenhuan YUAN, Shaofeng ZHANG, Haihui LU, Lixiang WEI, Russel J. Kerkman, Richard Lukaszewski, Ahmed Mohamed Sayed Ahmed, Robert J. Breitzmann
  • POWER CELL BYPASS METHOD AND APPARATUS FOR MULTILEVEL INVERTER
    Publication number: 20140268928
    Abstract: Multilevel inverters, power cells and bypass methods are presented in which a power cell switching circuit is selectively disconnected from the power cell output, and a bypass which is closed to connect first and second cell output terminals to selectively bypass a power stage of a multilevel inverter, with an optional AC input switch to selectively disconnect the AC input from the power cell switching circuit during bypass.
    Type: Application
    Filed: March 18, 2013
    Publication date: September 18, 2014
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: Lixiang Wei, Yuan Xiao, Haihui Lu, Douglas B. Weber
  • METHODS AND APPARATUS FOR CONTINUOUS AND DISCONTINUOUS ACTIVE RECTIFIER BOOST OPERATION TO INCREASE POWER CONVERTER RATING
    Publication number: 20140268954
    Abstract: Power conversion systems and operating methods are presented in which an active front end rectifier is operated in a boost mode using discontinuous pulse width modulation in a first range of DC bus voltage boost amount, and continuous space vector pulse width modulation is used in a second range, with the ranges being correlated to output derating with respect to filter inductor magnetics in the first range and to rectifier switching loss derating and the second range.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: Lixiang Wei, Yogesh Patel
  • METHOD TO IMPLEMENT DRIVE DIAGNOSTICS AND PROGNOSTICS AUTOMATICALLY
    Publication number: 20140265976
    Abstract: An electric motor drive system includes a fan configured to cool power electronic components of the electric motor drive system. The electric motor drive system also includes a temperature sensor disposed proximate an air inlet of the fan and configured to sense an ambient temperature of air entering the air inlet. In addition, the electric motor drive system includes a processor communicatively coupled to the temperature sensor and configured to determine at least one of a drive prognostic and a derating requirement based on the sensed ambient temperature.
    Type: Application
    Filed: March 14, 2013
    Publication date: September 18, 2014
    Applicant: ROCKWELL AUTOMATION TECHNOLOGIES, INC.
    Inventors: Bruce William Weiss, Robert Michael Michalski, Lixiang Wei, Garron Koch Morris, Brian Patrick Brown
  • ACTIVE FRONT END POWER CONVERTER WITH BOOST MODE DERATING TO PROTECT FILTER INDUCTOR
    Publication number: 20140268953
    Abstract: Methods and apparatus are presented for controlling a power converter to protect input filter inductors from overheating, in which an active front end (AFE) rectifier is operated in a boost mode to provide a boosted DC voltage at a derated output current value selected according to the DC bus voltage boost amount corresponding to a maximum load condition for which the filter inductors will not overheat.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: Yogesh Patel, Lixiang Wei
  • CONVERTER LIFETIME IMPROVEMENT METHOD FOR DOUBLY FED INDUCTION GENERATOR
    Publication number: 20140253055
    Abstract: The present techniques include methods and systems for operating converter to maintain a lifespan of the converter. In some embodiments, the operating frequency of the converter may be increased such that stress may be reduced on the bond wires of the converter. More specifically, embodiments involve calculating the aging parameters for certain operating conditions of the converter operating in a maximum power point tracking (MPPT) mode and determining whether the MPPT operation results in aging the converter to a point which reduces the converter lifespan below a desired lifespan. If the MPPT operation reduces the converter lifespan below the desired lifespan, the frequency of the converter may be increased such that the converter may be controlled to operate at a percentage of MPPT. Thus, in some embodiments, power output may be optimized with respect to maintaining a desired lifespan of the converter.
    Type: Application
    Filed: May 22, 2014
    Publication date: September 11, 2014
    Applicant: ROCKWELL AUTOMATION TECHNOLOGIES, INC.
    Inventors: Lixiang Wei, Russel J. Kerkman, Richard A. Lukaszewski, Haihui Lu, Zhenhuan Yuan
  • Apparatus and method for energy efficient motor drive standby operation
    Patent number: 8816631
    Abstract: Motor drive apparatus and methods are presented in which a standby controller uses at least one switching device to power an inverter in a normal mode and to remove power from the inverter and other motor drive components during a standby mode for improved energy efficiency.
    Type: Grant
    Filed: March 13, 2012
    Date of Patent: August 26, 2014
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Lixiang Wei, Yogesh Popatlal Patel, Brian P. Brown
  • SYSTEM FOR DETECTION OF A GROUND FAULT IN A HIGH RESISTANCE GROUND NETWORK
    Publication number: 20140225625
    Abstract: A method is provided for detection of a ground fault in a high resistance network in a voltage source power conversion circuit comprising a power converter that converts incoming AC power to DC power applied to a DC bus and an inverter that converts DC power from the DC bus to output AC power. The method includes detecting a midpoint-to-ground voltage between a low side of the DC bus and a ground potential and detecting the presence of a ground fault in a high resistance network based upon the detected midpoint-to-ground voltage.
    Type: Application
    Filed: April 14, 2014
    Publication date: August 14, 2014
    Applicant: ROCKWELL AUTOMATION TECHNOLOGIES, INC.
    Inventors: Lixiang Wei, Zhijun Liu, Brian Patrick Brown, David W. Kirschnik, Russ J. Kerkman, Richard A. Lukaszewski, Gary Skibinski, Carlos Daniel Rodriguez-Valdez
  • Converter lifetime improvement method for doubly fed induction generator
    Patent number: 8736091
    Abstract: The present techniques include methods and systems for operating converter to maintain a lifespan of the converter. In some embodiments, the operating frequency of the converter may be increased such that stress may be reduced on the bond wires of the converter. More specifically, embodiments involve calculating the aging parameters for certain operating conditions of the converter operating in a maximum power point tracking (MPPT) mode and determining whether the MPPT operation results in aging the converter to a point which reduces the converter lifespan below a desired lifespan. If the MPPT operation reduces the converter lifespan below the desired lifespan, the frequency of the converter may be increased such that the converter may be controlled to operate at a percentage of MPPT. Thus, in some embodiments, power output may be optimized with respect to maintaining a desired lifespan of the converter.
    Type: Grant
    Filed: June 18, 2010
    Date of Patent: May 27, 2014
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Lixiang Wei, Russel J. Kerkman, Richard A. Lukaszewski, Haihui Lu, Zhenhuan Yuan
  • DRIVE FAILURE PROTECTION
    Publication number: 20140132295
    Abstract: The present techniques include methods and systems for detecting a failure in a capacitor bank of an electrical drive system. Embodiments include using discharge resistors to discharge capacitors in the capacitor bank, forming a neutral node of the capacitor bank. In different capacitor configurations, the neutral node is measured, and the voltage is analyzed to determine whether a capacitor bank unbalance has occurred. In some embodiments, the node is a neutral-to-neutral node between the discharged side of the discharge resistors and a neutral side of the capacitor bank, or between the discharged side of the discharge resistors and a discharged side of a second set of discharge resistors. In some embodiments, the node is a neutral-to-ground node between the discharged side of the discharge resistors and a ground potential.
    Type: Application
    Filed: January 20, 2014
    Publication date: May 15, 2014
    Applicant: ROCKWELL AUTOMATION TECHNOLOGIES, INC.
    Inventors: Yuan Xiao, Lixiang Wei, Doyle F. Busse
  • System for detection of a ground fault in a high resistance ground network
    Patent number: 8698504
    Abstract: A method is provided for detection of a ground fault in a high resistance network in a voltage source power conversion circuit comprising a power converter that converts incoming AC power to DC power applied to a DC bus and an inverter that converts DC power from the DC bus to output AC power. The method includes detecting a midpoint-to-ground voltage between a low side of the DC bus and a ground potential and detecting the presence of a ground fault in a high resistance network based upon the detected midpoint-to-ground voltage.
    Type: Grant
    Filed: October 9, 2010
    Date of Patent: April 15, 2014
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Lixiang Wei, Zhijun Liu, Brian Patrick Brown, David W. Kirschnik, Russ J. Kerkman, Richard A. Lukaszewski, Gary Skibinski, Carlos Daniel Rodriguez-Valdez