Patents by Inventor Ehsan Al-Nabi

Ehsan Al-Nabi 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: 10848075
    Abstract: An active rectifier with a controller including a feedforward component, a modulator and a modulation index controller. The modulator generates switching control signals according to a reference to convert AC input power from the AC input to control the DC bus voltage at the DC output. The feedforward component computes the reference according to an estimated total inductance of the AC input, a grid voltage of the AC input, a modulation index reference, and a reactive power offset signal, and the modulation index controller computes the reactive power offset signal according to an error between the modulation index reference and a feedback modulation index.
    Type: Grant
    Filed: December 7, 2019
    Date of Patent: November 24, 2020
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Ahmed S. Mohamed Sayed Ahmed, Ehsan Al-Nabi, Zhendong Zhang, Sang Woo Nam
  • Patent number: 10811990
    Abstract: An active rectifier includes first and second DC nodes, a switching circuit, and a controller configured to compute a voltage reference according to a load signal of the DC output, and a non-linear relationship between a load condition of the DC output and a DC bus voltage at the DC output, and to generate rectifier switching control signals according to the voltage reference to cause the switching circuit to convert AC input power from the AC input to control the DC bus voltage at the DC output.
    Type: Grant
    Filed: March 29, 2019
    Date of Patent: October 20, 2020
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Ahmed S. Mohamed Sayed Ahmed, Lixiang Wei, Ehsan Al-Nabi, Nirav Patel, Sang Woo Nam
  • Publication number: 20200313565
    Abstract: An active rectifier includes first and second DC nodes, a switching circuit, and a controller configured to compute a voltage reference according to a load signal of the DC output, and a non-linear relationship between a load condition of the DC output and a DC bus voltage at the DC output, and to generate rectifier switching control signals according to the voltage reference to cause the switching circuit to convert AC input power from the AC input to control the DC bus voltage at the DC output.
    Type: Application
    Filed: March 29, 2019
    Publication date: October 1, 2020
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: Ahmed S. Mohamed Sayed Ahmed, Lixiang Wei, Ehsan Al-Nabi, Nirav Patel, Sang Woo Nam
  • Publication number: 20200313566
    Abstract: An active rectifier with a controller including a feedforward component, a modulator and a modulation index controller. The modulator generates switching control signals according to a reference to convert AC input power from the AC input to control the DC bus voltage at the DC output. The feedforward component computes the reference according to an estimated total inductance of the AC input, a grid voltage of the AC input, a modulation index reference, and a reactive power offset signal, and the modulation index controller computes the reactive power offset signal according to an error between the modulation index reference and a feedback modulation index.
    Type: Application
    Filed: December 7, 2019
    Publication date: October 1, 2020
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: Ahmed S. Mohamed Sayed Ahmed, Ehsan Al-Nabi, Zhendong Zhang, Sang Woo Nam
  • Patent number: 10680547
    Abstract: The disclosed examples provide an easy and low-loss solution to reduce voltage stress on motor and cable in inverter-fed motor systems by suppressing resonances on the motor cable with apparatus coupled between the inverter output and the motor cable. Disclosed examples include various methods to mitigate voltage stress on both motor and cable, including an output filter circuit with a cable side parallel RL circuit between an inverter output and a motor cable, and an inverter to provide an inverter output signal to the output filter circuit to drive a load through the motor cable, where the cable side parallel RL circuit includes a resistor coupled in series between the inverter output and the motor cable, and an inductor connected in parallel with the resistor.
    Type: Grant
    Filed: July 12, 2018
    Date of Patent: June 9, 2020
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Yuan Xiao, Ye Zhang, Ehsan Al-Nabi, Richard L. Piekarz
  • Publication number: 20200021234
    Abstract: The disclosed examples provide an easy and low-loss solution to reduce voltage stress on motor and cable in inverter-fed motor systems by suppressing resonances on the motor cable with apparatus coupled between the inverter output and the motor cable. Disclosed examples include various methods to mitigate voltage stress on both motor and cable, including an output filter circuit with a cable side parallel RL circuit between an inverter output and a motor cable, and an inverter to provide an inverter output signal to the output filter circuit to drive a load through the motor cable, where the cable side parallel RL circuit includes a resistor coupled in series between the inverter output and the motor cable, and an inductor connected in parallel with the resistor.
    Type: Application
    Filed: July 12, 2018
    Publication date: January 16, 2020
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: Yuan Xiao, Ye Zhang, Ehsan Al-Nabi, Richard L. Piekarz
  • Patent number: 10523128
    Abstract: An active rectifier with a controller including a feedforward component, a modulator and a modulation index controller. The modulator generates switching control signals according to a reference to convert AC input power from the AC input to control the DC bus voltage at the DC output. The feedforward component computes the reference according to an estimated total inductance of the AC input, a grid voltage of the AC input, a modulation index reference, and a reactive power offset signal, and the modulation index controller computes the reactive power offset signal according to an error between the modulation index reference and a feedback modulation index.
    Type: Grant
    Filed: March 29, 2019
    Date of Patent: December 31, 2019
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Ahmed S. Mohamed Sayed Ahmed, Ehsan Al-Nabi, Zhendong Zhang, Sang Woo Nam
  • Patent number: 9985565
    Abstract: Disclosed examples include motor drive power conversion systems with an inverter, as well as a controller methods to drive a motor in which output filter capacitor currents are computed and used to compensate the motor control in consideration of damping resistance values of an output filter.
    Type: Grant
    Filed: April 18, 2016
    Date of Patent: May 29, 2018
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Semyon Royak, Jingya Dai, Jingbo Liu, Thomas A. Nondahl, Ehsan Al-Nabi
  • Patent number: 9800190
    Abstract: Disclosed examples include power conversion systems, methods and computer readable mediums to operate an inverter to drive a motor load through an intervening filter, by computing a speed error value according to a speed reference value and a speed feedback value, computing a torque reference value according to the speed error value, computing a motor current reference value according to the torque reference value, compensating the motor current reference value according to capacitor currents of the output filter using a transfer function representing an output current to input current amplitude vs. frequency behavior of the output filter and the motor load, and controlling the inverter according to the inverter output current reference value.
    Type: Grant
    Filed: February 3, 2016
    Date of Patent: October 24, 2017
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Semyon Royak, Jingbo Liu, Jingya Dai, Thomas Nondahl, Ehsan Al-Nabi, Peter B. Schmidt
  • Publication number: 20170302209
    Abstract: Disclosed examples include motor drive power conversion systems with an inverter, as well as a controller methods to drive a motor in which output filter capacitor currents are computed and used to compensate the motor control in consideration of damping resistance values of an output filter.
    Type: Application
    Filed: April 18, 2016
    Publication date: October 19, 2017
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: Semyon Royak, Jingya Dai, Jingbo Liu, Thomas A. Nondahl, Ehsan Al-Nabi
  • Publication number: 20170222588
    Abstract: Disclosed examples include power conversion systems, methods and computer readable mediums to operate an inverter to drive a motor load through an intervening filter, by computing a speed error value according to a speed reference value and a speed feedback value, computing a torque reference value according to the speed error value, computing a motor current reference value according to the torque reference value, compensating the motor current reference value according to capacitor currents of the output filter using a transfer function representing an output current to input current amplitude vs. frequency behavior of the output filter and the motor load, and controlling the inverter according to the inverter output current reference value.
    Type: Application
    Filed: February 3, 2016
    Publication date: August 3, 2017
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: Semyon Royak, Jingbo Liu, Jingya Dai, Thomas Nondahl, Ehsan Al-Nabi, Peter B. Schmidt
  • Patent number: 9716460
    Abstract: Motor drive control apparatus and methods are presented for speed reversal control for drives used with output filters and transformers using a high or maximal drive current command to facilitate dissipation of regenerative energy seen in this system during speed reversal with open loop control to reverse the spin direction of a driven motor while quickly transitioning through zero speed.
    Type: Grant
    Filed: January 28, 2015
    Date of Patent: July 25, 2017
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Thomas Nondahl, Jingbo Liu, Semyon Royak, Peter B. Schmidt, Jingya Dai, Ehsan Al-nabi
  • Patent number: 9595896
    Abstract: Methods and systems are presented for closed loop motor speed and torque control without a sensor at the motor, in which configuration parameters are received from a user interface to define operating characteristics of a filter, a transformer, a cable, and the motor coupled with the output of a motor drive, and an object model of the motor drive is configured according to the filter, transformer, cable and motor configuration parameters to facilitate sensorless closed loop motor speed and/or torque control.
    Type: Grant
    Filed: December 16, 2015
    Date of Patent: March 14, 2017
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Semyon Royak, Thomas Nondahl, Jingya Dai, Thomas M. Cahill, Robert J. Breitzmann, Peter B. Schmidt, Jingbo Liu, Ehsan Al-Nabi
  • Patent number: 9490738
    Abstract: Disclosed examples include methods, computer readable mediums and motor drive power conversion systems for sensorless speed control of a motor driven by an inverter through an intervening filter, a transformer and a motor cable, in which sensorless vector control is used to regulate the motor speed based on a speed feedback value computed according to voltage or current values associated with the motor drive using an observer having formulas and impedance parameters of the filter, the transformer, the motor cable and the motor.
    Type: Grant
    Filed: February 25, 2016
    Date of Patent: November 8, 2016
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Thomas A. Nondahl, Jingbo Liu, Semyon Royak, Peter B. Schmidt, Ehsan Al-Nabi, Jingya Dai
  • Publication number: 20160218657
    Abstract: Motor drive control apparatus and methods are presented for speed reversal control for drives used with output filters and transformers using a high or maximal drive current command to facilitate dissipation of regenerative energy seen in this system during speed reversal with open loop control to reverse the spin direction of a driven motor while quickly transitioning through zero speed.
    Type: Application
    Filed: January 28, 2015
    Publication date: July 28, 2016
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: Thomas Nondahl, Jingbo Liu, Semyon Royak, Peter B. Schmidt, Jingya Dai, Ehsan Al-nabi
  • Patent number: 9374028
    Abstract: Motor drive control apparatus and methods are presented for sensorless control of a driven motor using open loop current regulated control during low-speed operation and an EMF-based position observer for position estimation during higher speed operation, with zero feedback speed during low-speed open-loop operation and feedback speed estimated by the EMF-based observer during high-speed operation and with velocity mode control over the full speed range and mode control hysteresis for smooth transitions between open loop and EMF-based observer control.
    Type: Grant
    Filed: December 10, 2014
    Date of Patent: June 21, 2016
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Thomas Nondahl, Jingbo Liu, Peter Schmidt, Semyon Royak, Jingya Dai, Ehsan Al-Nabi
  • Publication number: 20160173012
    Abstract: Disclosed examples include methods, computer readable mediums and motor drives power conversion systems for sensorless speed control of a motor driven by an inverter through an intervening filter, in which a controller computes motor current feedback values for a current control cycle according to inverter output current values, capacitance values representing capacitances of filter capacitors of the filter, filter output voltage values representing output voltages of the filter, and a speed feedback or reference value of a previous control cycle. The controller computes a speed feedback value for the current control cycle according to the motor current feedback values and the filter output voltage values, and controls the inverter to regulate the rotational speed of the motor at least partially according to the speed feedback or reference value using vector control.
    Type: Application
    Filed: February 25, 2016
    Publication date: June 16, 2016
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: Thomas A. Nondahl, Semyon Royak, Jingbo Liu, Jingya Dai, Ehsan Al-Nabi, Peter B. Schmidt
  • Publication number: 20160173018
    Abstract: Disclosed examples include methods, computer readable mediums and motor drive power conversion systems for sensorless speed control of a motor driven by an inverter through an intervening filter, a transformer and a motor cable, in which sensorless vector control is used to regulate the motor speed based on a speed feedback value computed according to voltage or current values associated with the motor drive using an observer having formulas and impedance parameters of the filter, the transformer, the motor cable and the motor.
    Type: Application
    Filed: February 25, 2016
    Publication date: June 16, 2016
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: Thomas A. Nondahl, Jingbo Liu, Semyon Royak, Peter B. Schmidt, Ehsan Al-Nabi, Jingya Dai
  • Patent number: 9294019
    Abstract: Power converters and methods are presented for driving an AC load connected through an intervening filter circuit, in which at least one filter current or voltage signal or value is determined according to feedback signals or values representing an output parameter at an AC output of the power converter, and AC electrical output power is generated at the AC output based at least partially on the at least one filter current or voltage signal or value.
    Type: Grant
    Filed: November 28, 2014
    Date of Patent: March 22, 2016
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Jingbo Liu, Thomas Nondahl, Peter Schmidt, Semyon Royak, Jingya Dai, Ehsan Al-Nabi
  • Publication number: 20160056740
    Abstract: Motor drive control apparatus and methods are presented for sensorless control of a driven motor using open loop current regulated control during low-speed operation and an EMF-based position observer for position estimation during higher speed operation, with zero feedback speed during low-speed open-loop operation and feedback speed estimated by the EMF-based observer during high-speed operation and with velocity mode control over the full speed range and mode control hysteresis for smooth transitions between open loop and EMF-based observer control.
    Type: Application
    Filed: December 10, 2014
    Publication date: February 25, 2016
    Applicant: ROCKWELL AUTOMATION TECHNOLOGIES, INC.
    Inventors: Thomas Nondahl, Jingbo Liu, Peter Schmidt, Semyon Royak, Jingya Dai, Ehsan Al-Nabi