Patents by Inventor Ahmed Mohamed Sayed Ahmed
Ahmed Mohamed Sayed Ahmed 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).
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Publication number: 20150153397Abstract: Impedance detection methods and systems are presented for automatic computation of an electrical component impedance value at one or more specific frequencies of interest using quadrature voltage and current values generated by quadrature tracking filters based on sensed or measured voltage and current signals or values and a base frequency input.Type: ApplicationFiled: December 3, 2013Publication date: June 4, 2015Applicant: ROCKWELL AUTOMATION TECHNOLOGIES, INC.Inventors: Russel J. Kerkman, Ahmed Mohamed Sayed Ahmed, Brian J. Seibel, Shiv Gupta, Prathamesh Ramesh Vadhavkar
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Patent number: 9041234Abstract: 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: GrantFiled: March 26, 2012Date of Patent: May 26, 2015Assignee: Rockwell Automation Technologies, Inc.Inventors: Haihui Lu, Zhenhuan Yuan, Lixiang Wei, Russel Kerkman, Richard Lukaszewski, Ahmed Mohamed Sayed Ahmed
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Publication number: 20150123700Abstract: Described herein are methods, systems, and apparatuses for determining sag in a signal. In one example, a method of tracking sag in a signal includes, when in an initial state, monitoring for when the signal transitions to a sag state based at least on an output of a tracking filter. In response to the signal transitioning to the sag state, increasing a bandwidth of the tracking filter and, when in the sag state, monitoring for when the signal transitions to a recovering state. The method further includes, in response to the signal transitioning to the recovering state, decreasing the bandwidth of the tracking filter.Type: ApplicationFiled: November 5, 2013Publication date: May 7, 2015Applicant: ROCKWELL AUTOMATION TECHNOLOGIES, INC.Inventors: Ahmed Mohamed sayed ahmed, Brian J. Seibel, Russel Kerkman
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Patent number: 8988026Abstract: 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: GrantFiled: July 31, 2012Date of Patent: March 24, 2015Assignee: Rockwell Automation Technologies, Inc.Inventors: Ahmed Mohamed Sayed Ahmed, Lixiang Wei, Brian J. Seibel
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Publication number: 20150077167Abstract: A phase angle detector with a PLL, a power converter, and a method for reducing offsets in an input signal, in which an adaptive offset processor selectively removes a DC offset component from the input signal to generate a modified signal including a fundamental frequency component and higher order harmonics of the input signal with the DC offset component removed, and the PLL provides a phase angle signal at least partially according to the modified signal.Type: ApplicationFiled: November 24, 2014Publication date: March 19, 2015Applicant: Rockwell Automation Technologies, Inc.Inventors: Russel J. Kerkman, Ahmed Mohamed Sayed Ahmed, Brian J. Seibel
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Patent number: 8964427Abstract: A phase angle detector with a PLL, a power converter, and a method for reducing offsets in an input signal, in which an adaptive offset processor selectively removes a DC offset component from the input signal to generate a modified signal including a fundamental frequency component and higher order harmonics of the input signal with the DC offset component removed, and the PLL provides a phase angle signal at least partially according to the modified signal.Type: GrantFiled: June 29, 2012Date of Patent: February 24, 2015Assignee: Rockwell Automation Technologies, Inc.Inventors: Russel J. Kerkman, Ahmed Mohamed Sayed Ahmed, Brian J. Seibel
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Publication number: 20140265596Abstract: 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: ApplicationFiled: March 14, 2013Publication date: September 18, 2014Applicant: 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
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Patent number: 8816729Abstract: Methods and systems for synchronizing an electric grid having unbalanced voltages are provided. A voltage vector may be filtered in a quadrature tracking filter (QTF) to generate a quadrature signal. The inputs to the QTF may be either single input, multiple outputs, or alternatively, multiple inputs, multiple outputs. Furthermore, the second state of either of the two QTF transformations may be either positive or negative. A phase-locked-loop (PLL) operation may be performed on the quadrature signal to monitor a voltage vector between the grid and a connected power converter. The QTF and PLL methods are suitable for either single-phase applications or n-phase (any number of phases) applications.Type: GrantFiled: May 10, 2012Date of Patent: August 26, 2014Assignee: Rockwell Automation Technologies, Inc.Inventors: Russel J. Kerkman, Ahmed Mohamed Sayed Ahmed, Brian J. Seibel, Carlos Rodriguez Valdez
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Patent number: 8816625Abstract: Integrated AC regenerative motor drives and operating methods are presented in which a precharging circuit is provided with an IGBT, a diode and a parallel current limiting component in an intermediate DC circuit between a switching rectifier and an output inverter, and the drive is operated in one of three modes for motoring, regenerating and precharging.Type: GrantFiled: October 27, 2011Date of Patent: August 26, 2014Assignee: Rockwell Automation Technologies, Inc.Inventors: Jeremiah Kopiness, Raymond G. Sladky, Ahmed Mohamed sayed ahmed
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Patent number: 8704571Abstract: Methods and systems for synchronizing an electric grid having unbalanced voltages are provided. A voltage vector may be filtered in a quadrature tracking filter (QTF) to generate a quadrature signal. A phase-locked-loop (PLL) operation may be performed on the quadrature signal to monitor a voltage vector between the grid and a connected power converter. The QTF and PLL methods are suitable for either single-phase applications or n-phase (any number of phases) applications. A frequency estimator estimates the grid frequency of the electric grid and outputs the estimated frequency to the QTF algorithms. The frequency estimator may include a three-phase phase-locked-loop (three-phase PLL) suitable for estimating the center frequencies of multiple phases of the electric grid. The frequency estimator may also include means for reducing the harmonics in the grid system.Type: GrantFiled: May 10, 2012Date of Patent: April 22, 2014Assignee: Rockwell Automation Technologies, Inc.Inventors: Russel J. Kerkman, Ahmed Mohamed Sayed Ahmed, Brian J. Seibel, Carlos Rodriguez Valdez
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Publication number: 20140035492Abstract: 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: ApplicationFiled: July 31, 2012Publication date: February 6, 2014Applicant: Rockwell Automation Technologies, Inc.Inventors: Ahmed Mohamed Sayed Ahmed, Lixiang Wei, Brian J. Seibel
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Publication number: 20140003102Abstract: A phase angle detector with a PLL, a power converter, and a method for reducing offsets in an input signal, in which an adaptive offset processor selectively removes a DC offset component from the input signal to generate a modified signal including a fundamental frequency component and higher order harmonics of the input signal with the DC offset component removed, and the PLL provides a phase angle signal at least partially according to the modified signal.Type: ApplicationFiled: June 29, 2012Publication date: January 2, 2014Applicant: ROCKWELL AUTOMATION TECHNOLOGIES, INC.Inventors: Russel J. Kerkman, Ahmed Mohamed Sayed Ahmed, Brian J. Seibel
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Patent number: 8570003Abstract: A double fed induction generator (DFIG) system and controller are presented in which the rotor side converter is preloaded with one or more initial values for resuming regulated operation to counteract transients upon deactivation of the crowbar protection circuit to provide grid fault ride through.Type: GrantFiled: April 13, 2011Date of Patent: October 29, 2013Assignee: Rockwell Automation Technologies, Inc.Inventors: Haihui Lu, Zhenhuan Yuan, Lixiang Wei, Russel Kerkman, Richard Lukaszewski, Ahmed Mohamed Sayed Ahmed
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Patent number: 8570773Abstract: A three-phase power converter includes a converter configured to convert a three phase AC power input to a DC power output, the DC power output being provided to high and low sides of a DC bus, and an inverter coupled to the DC bus and configured to convert the DC power to a three phase AC output. The inverter comprises three legs and each leg comprises a pair of solid state switches and a respective output therebetween. The power converter further includes a common mode voltage control filter comprising three filter inputs and two filter outputs, each filter input coupled to an output of a respective leg of the inverter and each filter output coupled to a respective side of the DC bus.Type: GrantFiled: May 26, 2010Date of Patent: October 29, 2013Assignee: Rockwell Automation Technologies, Inc.Inventors: Gary L. Skibinski, Ahmed Mohamed Sayed Ahmed
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Publication number: 20130249501Abstract: 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: ApplicationFiled: March 26, 2012Publication date: September 26, 2013Applicant: Rockwell Automation Technologies, Inc.Inventors: Haihui Lu, Zhenhuan Yuan, Lixiang Wei, Russel Kerkman, Richard Lukaszewski, Ahmed Mohamed Sayed Ahmed
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Publication number: 20130120038Abstract: Methods and systems for synchronizing an electric grid having unbalanced voltages are provided. A voltage vector may be filtered in a quadrature tracking filter (QTF) to generate a quadrature signal. A phase-locked-loop (PLL) operation may be performed on the quadrature signal to monitor a voltage vector between the grid and a connected power converter. The QTF and PLL methods are suitable for either single-phase applications or n-phase (any number of phases) applications. A frequency estimator estimates the grid frequency of the electric grid and outputs the estimated frequency to the QTF algorithms. The frequency estimator may include a three-phase phase-locked-loop (three-phase PLL) suitable for estimating the center frequencies of multiple phases of the electric grid. The frequency estimator may also include means for reducing the harmonics in the grid system.Type: ApplicationFiled: May 10, 2012Publication date: May 16, 2013Applicant: Rockwell Automation Technologies, Inc.Inventors: Russel J. Kerkman, Ahmed Mohamed Sayed Ahmed, Brian J. Seibel, Carlos Rodriguez Valdez
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Publication number: 20130120039Abstract: Methods and systems for synchronizing an electric grid having unbalanced voltages are provided. A voltage vector may be filtered in a quadrature tracking filter (QTF) to generate a quadrature signal. The inputs to the QTF may be either single input, multiple outputs, or alternatively, multiple inputs, multiple outputs. Furthermore, the second state of either of the two QTF transformations may be either positive or negative. A phase-locked-loop (PLL) operation may be performed on the quadrature signal to monitor a voltage vector between the grid and a connected power converter. The QTF and PLL methods are suitable for either single-phase applications or n-phase (any number of phases) applications.Type: ApplicationFiled: May 10, 2012Publication date: May 16, 2013Applicant: Rockwell Automation Technologies, Inc.Inventors: Russel J. Kerkman, Ahmed Mohamed Sayed Ahmed, Brian J. Seibel, Carlos Rodriguez Valdez
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Patent number: 8373406Abstract: Electrical power quality test circuitry for testing response of an electrical device to input power disturbances is provided. The test circuitry includes a power structure having a rectifier configured to convert incoming AC voltage to DC voltage on a DC bus, and a power inverter configured to convert DC voltage from the bus to three-phase output AC voltage applied to the electrical device. The test circuitry also includes a control circuit configured to apply control signals to at least the power inverter to emulate at least one of a change in the amplitude of at least one phase of the output AC voltage at least one phase angle of at least one phase of the output AC voltage, and a frequency change for all phases of the output AC voltage.Type: GrantFiled: July 30, 2009Date of Patent: February 12, 2013Assignee: Rockwell Automation Technologies, Inc.Inventors: Ahmed Mohamed Sayed Ahmed, Gary L. Skibinski, Richard A. Lukaszewski
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Publication number: 20120262129Abstract: A double fed induction generator (DFIG) system and controller are presented in which the rotor side converter is preloaded with one or more initial values for resuming regulated operation to counteract transients upon deactivation of the crowbar protection circuit to provide grid fault ride through.Type: ApplicationFiled: April 13, 2011Publication date: October 18, 2012Applicant: ROCKWELL AUTOMATION TECHNOLOGIES, INC.Inventors: Haihui Lu, Zhenhuan Yuan, Lixiang Wei, Russel Kerkman, Richard Lukaszewski, Ahmed Mohamed Sayed Ahmed
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Publication number: 20110292695Abstract: A three-phase power converter includes a converter configured to convert a three phase AC power input to a DC power output, the DC power output being provided to high and low sides of a DC bus, and an inverter coupled to the DC bus and configured to convert the DC power to a three phase AC output. The inverter comprises three legs and each leg comprises a pair of solid state switches and a respective output therebetween. The power converter further includes a common mode voltage control filter comprising three filter inputs and two filter outputs, each filter input coupled to an output of a respective leg of the inverter and each filter output coupled to a respective side of the DC bus.Type: ApplicationFiled: May 26, 2010Publication date: December 1, 2011Applicant: Rockwell Automation Technologies, Inc.Inventors: Gary L. Skibinski, Ahmed Mohamed Sayed Ahmed