Patents by Inventor Navid R. Zargari
Navid R. Zargari 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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Patent number: 11469685Abstract: Power conversion systems and methods to control a multiphase multilevel regenerative power converter with multilevel phase circuits that individually include multiple regenerative power stages with respective power stage outputs connected in series, each of the multiple regenerative power stages comprising a DC link circuit a switching rectifier coupled between a respective transformer secondary circuit and the DC link circuit, and a switching inverter coupled between the DC link circuit and the respective power stage output, including a controller that provides inverter switching control signals to control the respective switching inverters, provides rectifier switching control signals to control the respective switching rectifiers, and controls a non-zero phase relationship between the rectifier switching control signals of the respective switching rectifiers.Type: GrantFiled: December 21, 2020Date of Patent: October 11, 2022Assignee: ROCKWELL AUTOMATION TECHNOLOGIES, INC.Inventors: Zhituo Ni, Mehdi Narimani, Zhongyuan Cheng, Navid R. Zargari
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Patent number: 11437938Abstract: A system is provided for driving multiple motors. The system includes multiple cascaded H-bridge (CHB) power inverters, a DC bus, and multiple neutral point converter/inverters. Each of the multiple CHB power inverters is connected to a respective motor at one or more AC terminals of the CHB power inverter. Each of the multiple CHB power inverters includes one or more DC terminals configured to receive DC power. Each of the multiple neutral point converter/inverters is connected to a respective CHB power inverter at one or more neutral terminals of the respective CHB power inverter and connected to the DC bus.Type: GrantFiled: September 29, 2020Date of Patent: September 6, 2022Assignee: ROCKWELL AUTOMATION TECHNOLOGIES, INC.Inventors: Navid R. Zargari, Zhongyuan Cheng, Mehdi Narimani, Ahmed Hisham Abuelnaga
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Publication number: 20220200479Abstract: Power conversion systems and methods to control a multiphase multilevel regenerative power converter with multilevel phase circuits that individually include multiple regenerative power stages with respective power stage outputs connected in series, each of the multiple regenerative power stages comprising a DC link circuit a switching rectifier coupled between a respective transformer secondary circuit and the DC link circuit, and a switching inverter coupled between the DC link circuit and the respective power stage output, including a controller that provides inverter switching control signals to control the respective switching inverters, provides rectifier switching control signals to control the respective switching rectifiers, and controls a non-zero phase relationship between the rectifier switching control signals of the respective switching rectifiers.Type: ApplicationFiled: December 21, 2020Publication date: June 23, 2022Inventors: Zhituo Ni, Mehdi Narimani, Zhongyuan Cheng, Navid R. Zargari
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Patent number: 11362595Abstract: For power converter pre-charge with line synchronization, a method magnetizes a power transformer of a power converter with a supply voltage from a variable voltage variable frequency supply. The method pre-charges power cells of the power converter fed from the power transformer to a specified voltage with the supply voltage. The method further modifies a primary amplitude, a primary phase, and a primary frequency of a primary winding of the power converter with the supply voltage to match a main amplitude, a main phase, and a main frequency of a main voltage of a main power source. In response to matching the primary amplitude, the primary phase, and the primary frequency to the main amplitude, the main phase, and the main frequency, the method connects the main power source to the power transformer.Type: GrantFiled: January 26, 2021Date of Patent: June 14, 2022Assignee: Rockwell Automation Technologies, Inc.Inventors: Marius G. Chis, Zhong Y. Cheng, Navid R. Zargari
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Patent number: 11342878Abstract: A regenerative power conversion system with a phase shift transformer having a primary circuit and N secondary sets of M secondary circuits, a controller synchronizes rectifier switching control signals of individual regenerative power stages to a phase angle of a corresponding one of the secondary circuits based on a feedback signal of the primary circuit during regenerative operation of the power conversion system.Type: GrantFiled: April 9, 2021Date of Patent: May 24, 2022Assignee: Rockwell Automation Technologies, Inc.Inventors: Ahmed Hisham Abuelnaga, Mehdi Narimani, Zhongyuan Cheng, Navid R. Zargari
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Publication number: 20220103098Abstract: A system is provided for driving multiple motors. The system includes multiple cascaded H-bridge (CHB) power inverters, a DC bus, and multiple neutral point converter/inverters. Each of the multiple CHB power inverters is connected to a respective motor at one or more AC terminals of the CHB power inverter. Each of the multiple CHB power inverters includes one or more DC terminals configured to receive DC power. Each of the multiple neutral point converter/inverters is connected to a respective CHB power inverter at one or more neutral terminals of the respective CHB power inverter and connected to the DC bus.Type: ApplicationFiled: September 29, 2020Publication date: March 31, 2022Inventors: Navid R. Zargari, Zhongyuan Cheng, Mehdi Narimani, Ahmed Hisham Abuelnaga
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Patent number: 11211879Abstract: A power conversion system and controller configured to generate a real average DC current reference based on a DC bus voltage of a DC link circuit and a DC bus voltage setpoint, generate real and reactive ripple current references based on the DC bus voltage of the DC link circuit and a ripple angle of the DC link circuit, and generate rectifier switching control signals to operate rectifier switching devices based on the real average DC current reference and the real and reactive ripple current references.Type: GrantFiled: September 23, 2019Date of Patent: December 28, 2021Assignee: Rockwell Automation Technologies, Inc.Inventors: Ahmed Hisham Abuelnaga, Zhituo Ni, Mehdi Narimani, Zhongyuan Cheng, Navid R. Zargari
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Publication number: 20210091681Abstract: A power conversion system and controller configured to generate a real average DC current reference based on a DC bus voltage of a DC link circuit and a DC bus voltage setpoint, generate real and reactive ripple current references based on the DC bus voltage of the DC link circuit and a ripple angle of the DC link circuit, and generate rectifier switching control signals to operate rectifier switching devices based on the real average DC current reference and the real and reactive ripple current references.Type: ApplicationFiled: September 23, 2019Publication date: March 25, 2021Applicant: Rockwell Automation Technologies, Inc.Inventors: Ahmed Hisham Abuelnaga, Zhituo Ni, Mehdi Narimani, Zhongyuan Cheng, Navid R. Zargari
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Publication number: 20210058003Abstract: Power conversion systems and methods to control a multiphase multilevel regenerative power converter with multilevel phase circuits that individually include multiple regenerative power stages with respective power stage outputs connected in series, the individual power stages comprising a DC link circuit a switching rectifier coupled between a respective transformer secondary circuit and the DC link circuit, and a switching inverter coupled between the DC link circuit and the respective power stage output, including a controller that provides inverter switching control signals to control the respective switching inverters, provides rectifier switching control signals to control the respective switching rectifiers, and controls a non-zero phase relationship between the rectifier switching control signals of the respective switching rectifiers.Type: ApplicationFiled: August 21, 2019Publication date: February 25, 2021Applicant: Rockwell Automation Technologies, Inc.Inventors: Zhituo Ni, Mehdi Narimani, Zhongyuan Cheng, Navid R. Zargari
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Patent number: 10924025Abstract: For a power supply with a reduced number of semiconductor devices, a transformer receives a three-phase primary voltage and steps the three-phase primary voltage up or down to a secondary voltage with a plurality of secondary winding sets to a plurality of first phase voltages, a plurality of second phase voltages, and a plurality of third phase voltages. A plurality of power cell sets each include a plurality of power cells cascaded connected. Each power cell comprises a rectifier and an inverter. The rectifier includes two first active switches that are serially connected and receive a phase voltage at a first switch midpoint, two second active switches that are serially connected and receive another phase voltage at a second switch midpoint, and two capacitors that are serially connected and receive another phase voltage at a capacitor midpoint between the capacitors.Type: GrantFiled: November 27, 2019Date of Patent: February 16, 2021Assignee: Rockwell Automation Technologies, Inc.Inventors: Navid R. Zargari, Sarah Badawi, Zhong Y. Cheng, Mehdi Narimani, Ye Zhang
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Patent number: 10924026Abstract: For a power supply with a reduced number of semiconductor devices, a transformer receives a three-phase primary voltage and steps the three-phase primary voltage up or down to a secondary voltage with a plurality of secondary winding sets to a plurality of first phase voltages, a plurality of second phase voltages, and a plurality of third phase voltages. A plurality of power cell sets each include a plurality of power cells cascaded connected. Each power cell comprises a rectifier and an inverter. The rectifier includes two first active switches that are serially connected and receive a phase voltage at a first switch midpoint, two second active switches that are serially connected and receive another phase voltage at a second switch midpoint, and two capacitors that are serially connected and receive another phase voltage at a capacitor midpoint between the capacitors.Type: GrantFiled: April 1, 2020Date of Patent: February 16, 2021Assignee: Rockwell Automation Technologies, Inc.Inventors: Navid R. Zargari, Sarah Badawi, Zhong Y. Cheng, Mehdi Narimani, Ye Zhang
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Publication number: 20200343821Abstract: For a power supply with a reduced number of semiconductor devices, a transformer receives a three-phase primary voltage and steps the three-phase primary voltage up or down to a secondary voltage with a plurality of secondary winding sets to a plurality of first phase voltages, a plurality of second phase voltages, and a plurality of third phase voltages. A plurality of power cell sets each include a plurality of power cells cascaded connected. Each power cell comprises a rectifier and an inverter. The rectifier includes two first active switches that are serially connected and receive a phase voltage at a first switch midpoint, two second active switches that are serially connected and receive another phase voltage at a second switch midpoint, and two capacitors that are serially connected and receive another phase voltage at a capacitor midpoint between the capacitors.Type: ApplicationFiled: April 1, 2020Publication date: October 29, 2020Inventors: Navid R. Zargari, Sarah Badawi, Zhong Y. Cheng, Mehdi Narimani, Ye Zhang
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Publication number: 20200343820Abstract: For a power supply with a reduced number of semiconductor devices, a transformer receives a three-phase primary voltage and steps the three-phase primary voltage up or down to a secondary voltage with a plurality of secondary winding sets to a plurality of first phase voltages, a plurality of second phase voltages, and a plurality of third phase voltages. A plurality of power cell sets each include a plurality of power cells cascaded connected. Each power cell comprises a rectifier and an inverter. The rectifier includes two first active switches that are serially connected and receive a phase voltage at a first switch midpoint, two second active switches that are serially connected and receive another phase voltage at a second switch midpoint, and two capacitors that are serially connected and receive another phase voltage at a capacitor midpoint between the capacitors.Type: ApplicationFiled: November 27, 2019Publication date: October 29, 2020Inventors: Navid R. Zargari, Sarah Badawi, Zhong Y. Cheng, Mehdi Narimani, Ye Zhang
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Patent number: 10651760Abstract: For a power supply with a reduced number of semiconductor devices, a phase shifting transformer receives a three-phase primary voltage and steps the three-phase primary voltage one of up and down to a secondary voltage with a plurality of secondary winding sets. There is phase shifting between different secondary winding sets. A plurality of power cell sets each comprise a plurality of power cells cascaded connected, and each power cell receives one of a single phase and a three-phase voltage of a distinct secondary winding set of the phase shifting transformer. Each power cell comprises no more than eight power semiconductor devices organized as a rectifier and an inverter. Each power semiconductor device is one of a diode and an active switch. Each power cell set generates one phase of a three-phase alternating current output.Type: GrantFiled: April 24, 2019Date of Patent: May 12, 2020Assignee: Rockwell Automation Technologies, IncInventors: Zhong Y. Cheng, Navid R. Zargari, Ye Zhang
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Patent number: 10389263Abstract: Motor drive power conversion systems are provided including a rectifier and a switching inverter, wherein the switching devices of the rectifier, the inverter and/or of a DC/DC converter are silicon carbide switches, such as silicon carbide MOSFETs. Driver circuits are provided for providing bipolar gate drive signals to the silicon carbide MOSFETs, including providing negative gate-source voltage for controlling the off state of enhancement mode low side drivers and positive gate-source voltage for controlling the off state of enhancement mode high side drivers.Type: GrantFiled: October 2, 2017Date of Patent: August 20, 2019Assignee: Rockwell Automation Technologies, Inc.Inventors: Kevin Baumann, Richard Lukaszewski, Rangarajan Tallam, Lixiang Wei, Lee Gettelfinger, Garron Morris, Bruce Weiss, Neil Gollhardt, Navid R. Zargari, William Brumsickle, Robert Wright Reese, Stephen E. Denning
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Publication number: 20190214899Abstract: 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 first and second 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: ApplicationFiled: March 14, 2019Publication date: July 11, 2019Applicant: Rockwell Automation Technologies, Inc.Inventors: Navid R. Zargari, Yuan Xiao, Lixiang Wei, Zhongyuan Cheng
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Patent number: 10305368Abstract: 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 first and second 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: GrantFiled: January 22, 2018Date of Patent: May 28, 2019Assignee: Rockwell Automation Technologies, Inc.Inventors: Navid R. Zargari, Yuan Xiao, Lixiang Wei, Zhongyuan Cheng
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Publication number: 20180145578Abstract: 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 first and second 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: ApplicationFiled: January 22, 2018Publication date: May 24, 2018Applicant: Rockwell Automation Technologies, Inc.Inventors: Navid R. Zargari, Yuan Xiao, Lixiang Wei, Zhongyuan Cheng
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Patent number: 9923469Abstract: Disclosed examples include methods, power converters and damping circuits to control damping of an input filter circuit, in which a low-voltage secondary winding is wound around a common core with a primary winding connected between an AC input and a rectifier input of the converter, where the secondary winding is coupled in a series circuit with a damping resistor and a switch, and a controller selectively closes the switch with a controlled on-time at system power up and/or in response to detection of oscillation or transients in the power converter.Type: GrantFiled: May 9, 2016Date of Patent: March 20, 2018Assignee: Rockwell Automation Technologies, Inc.Inventors: Yuan Xiao, Zhongyuan Cheng, Lixiang Wei, Navid R. Zargari
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Patent number: 9912221Abstract: 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 first and second 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: GrantFiled: August 3, 2016Date of Patent: March 6, 2018Assignee: Rockwell Automation Technologies, Inc.Inventors: Navid R. Zargari, Yuan Xiao, Lixiang Wei, Zhongyuan Cheng