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).

  • SYSTEMS AND METHODS FOR TESTING MOTOR DRIVES
    Publication number: 20150253381
    Abstract: Systems and methods for testing a motor drive are disclosed. The techniques enhance motor drive testing by not using a dyne-unit, thereby reducing the initial installation costs, maintenance costs, and size of the setup. The setup may include a rectifier and an inverter configured to operate in an active-reactive power control mode during testing under a simulated load by generating the corresponding active (P) and reactive (Q) power (e.g., torque and flux, respectively). The active-reactive power control mode may receive a desired P and Q and determine one or more gate drive signals to provide to switches in the rectifier and/or the inverter based on the desired P and Q, where the gate drive signals are configured to operate the rectifier and/or the inverter under a simulated load. The gate drive signals may be transmitted to the rectifier and/or the inverter accordingly.
    Type: Application
    Filed: March 5, 2014
    Publication date: September 10, 2015
    Applicant: ROCKWELL AUTOMATION TECHNOLOGIES, INC.
    Inventors: Yogesh Patel, Lixiang Wei
  • DOUBLE FED INDUCTION GENERATOR (DFIG) CONVERTER AND METHOD FOR IMPROVED GRID FAULT RIDETHROUGH
    Publication number: 20150229257
    Abstract: A double fed induction generator (DFIG) converter, methods and computer readable mediums are presented in which rotor side current spikes are attenuated by selectively activating at least one series damping circuit to conduct current through a series damping circuit resistance coupled in series between one or more DFIG rotor leads and a grid side converter in response to a grid fault occurrence or a grid fault clearance, and selectively bypassing the series damping circuit resistance after activating the series damping circuit.
    Type: Application
    Filed: April 27, 2015
    Publication date: August 13, 2015
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: Haihui Lu, Zhenhuan Yuan, Lixiang Wei, Russel J. Kerkman, Richard Lukaszewski, Ahmed Mohamed Sayed Ahmed
  • Fault identification techniques for high resistance grounded systems
    Patent number: 9091742
    Abstract: The present techniques include methods and systems for detecting a high resistive ground fault condition in an HRG system. Embodiments include systems and methods of measuring drive voltages and detecting voltage changes in the drive once the drive is in operation, particularly for drives operating at relatively low voltages and frequencies. In some embodiments, an integrator is utilized to detect peaks in the measured voltage changes. Relatively small ground currents are also measured to determine HRG faults. Moreover, in some embodiments, the detection of an HRG fault for one of several motor drives provide indication for the particular motor drive in fault.
    Type: Grant
    Filed: February 20, 2012
    Date of Patent: July 28, 2015
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Lixiang Wei, Zhijun Liu
  • Method to implement drive diagnostics and prognostics automatically
    Patent number: 9092030
    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: Grant
    Filed: March 14, 2013
    Date of Patent: July 28, 2015
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Bruce William Weiss, Robert Michael Michalski, Lixiang Wei, Garron Koch Morris, Brian Patrick Brown
  • METHOD AND APPARATUS FOR BYPASSING CASCADED H-BRIDGE (CHB) POWER CELLS AND POWER SUB CELL FOR MULTILEVEL INVERTER
    Publication number: 20150171733
    Abstract: Multilevel power converters, power cells and methods are presented for selectively bypassing a power stage of a multilevel inverter circuit, in which a single relay or contactor includes one or more normally closed output control contacts coupled between a given power cell switching circuit and the given power cell output, along with a normally open bypass contact coupled across the power stage output, with a local or central controller energizing the coil of the relay or contactor of a given cell to bypass that cell.
    Type: Application
    Filed: February 23, 2015
    Publication date: June 18, 2015
    Applicant: ROCKWELL AUTOMATION TECHNOLOGIES, INC.
    Inventors: Navid R. Zargari, Yuan Xiao, Lixiang Wei, Zhongyuan Cheng
  • Power converter and integrated DC choke therefor
    Patent number: 9054599
    Abstract: A power conversion system with multiple parallel connected motor drives including a plurality of rectifiers and a corresponding inverters connected by windings of a single common mode choke.
    Type: Grant
    Filed: March 15, 2012
    Date of Patent: June 9, 2015
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Lixiang Wei, Yuan Xiao, Navid Zargari, Richard Lukaszewski
  • Methods and apparatus for continuous and discontinuous active rectifier boost operation to increase power converter rating
    Patent number: 9054586
    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: Grant
    Filed: March 15, 2013
    Date of Patent: June 9, 2015
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Lixiang Wei, Yogesh Patel
  • Adjustable speed drive lifetime improvement system
    Patent number: 9048755
    Abstract: The present techniques include methods and systems for operating an inverter to maintain a lifespan of the inverter. In some embodiments, the switching frequency and/or the output current of the inverter may be changed such that stress may be reduced on the inverter bond wires of the inverter. More specifically, embodiments involve calculating the aging parameters for certain operating conditions of the inverter and determining whether the operating conditions result in aging the inverter to a point which reduces the inverter lifespan below a desired lifespan. If the operating conditions reduce the inverter lifespan below the desired lifespan, the switching frequency may be reduced to a lower or minimum switching frequency of the inverter and/or the output current of the inverter may be reduced to a maximum output current at the minimum switching frequency.
    Type: Grant
    Filed: June 25, 2013
    Date of Patent: June 2, 2015
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Lixiang Wei, Richard A. Lukaszewski, Russel J. Kerkman
  • METHOD AND APPARATUS FOR CURRENT AUTO BALANCING FOR PARALLEL CONVERTER SYSTEMS
    Publication number: 20150145462
    Abstract: Parallel converter current imbalance control apparatus and methods in which individual converter AC currents are measured for each phase, and the AC voltage control modulation indices associated with the converters having the highest and lowest AC currents for a given phase are adjusted to counteract current imbalance between the converters.
    Type: Application
    Filed: November 25, 2013
    Publication date: May 28, 2015
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: James A. Ulrich, Lixiang Wei, Jerome D. Rabe, Joseph D. Riley
  • DC pre-charge circuit
    Patent number: 9042146
    Abstract: Systems and methods are provided for pre-charging the DC bus on a motor drive. 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, and so forth. 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 to isolate a motor drive from the common DC bus under certain fault conditions.
    Type: Grant
    Filed: July 13, 2012
    Date of Patent: May 26, 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
  • Double fed induction generator (DFIG) converter and method for improved grid fault ridethrough
    Patent number: 9041234
    Abstract: A double fed induction generator (DFIG) converter method are presented in which rotor side current spikes are attenuated using series-connected damping resistance in response to grid fault occurrences or grid fault clearances.
    Type: Grant
    Filed: March 26, 2012
    Date of Patent: May 26, 2015
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Haihui Lu, Zhenhuan Yuan, Lixiang Wei, Russel Kerkman, Richard Lukaszewski, Ahmed Mohamed Sayed Ahmed
  • 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
  • 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
  • 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
  • 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