Patents by Inventor Vesna R. Mirkovic

Vesna R. Mirkovic 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: 8260464
    Abstract: A control technique for use in a fuel processor is disclosed. In one aspect, a control system includes a subsystem manager controller the operation of a respective physical subsystem for each of a plurality of physical subsystems in the fuel processor. The subsystem managers take their direction from a master control manager. In a second aspect, the subsystem managers collectively form a layer operating in conjunction with a second layer capable of interfacing the subsystem managers to their respective physical subsystems, a third layer capable of interfacing the subsystem managers with the second layer. In a third aspect, master control manager manages the operation of each physical subsystem through a respective subsystem manager, directs state transitions of the subsystem managers, and routs interaction between the subsystem managers from the master control manager.
    Type: Grant
    Filed: November 14, 2007
    Date of Patent: September 4, 2012
    Assignee: Texaco Inc.
    Inventors: Vesna R. Mirkovic, W. Spencer Wheat, Hugh N. To, Dennis J. Benedetto
  • Patent number: 8177545
    Abstract: A method for operating a combustor having a catalyst bed. The method includes the steps of directing a flow of air through a catalyst bed, providing heat to the catalyst bed, sensing the temperature in an upstream portion of the catalyst bed to provide an upstream temperature, directing a flow of a fuel through the catalyst bed when the upstream temperature reaches a light-off temperature to produce a combustion reaction, increasing the flow of the fuel until the flow of air and the flow of fuel have a selected air to fuel ratio, and controlling the combustion reaction within the catalyst bed by adjusting the flow of air and the flow of fuel while maintaining the selected air to fuel ratio. The method can include sensing temperatures within the catalyst bed and controlling the combustion reaction in response to the sensed temperatures. The heat provided to the catalyst bed can also be adjusted in response to the sensed temperatures.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: May 15, 2012
    Assignee: Texaco Inc.
    Inventors: Hongqiao Sun, Vesna R. Mirkovic, Bhaskar Balasubramanian, W. Spencer Wheat
  • Patent number: 8153311
    Abstract: The present invention provides a method and apparatus for identifying an activation of a burst disk. A pressure data or a temperature data relating to a flow is received. A determination is made whether the flow is interrupted based upon the at least one of the pressure data and the temperature data. A burst disk activation is identified in response to determining that the flow is interrupted.
    Type: Grant
    Filed: November 3, 2005
    Date of Patent: April 10, 2012
    Assignee: Texaco Inc. and Texaco Development Corporation
    Inventors: W. Spencer Wheat, Vesna R. Mirkovic, Ralph S. Worsley
  • Patent number: 8119299
    Abstract: A coolant subsystem for use in a fuel processor and a method for its operation are disclosed. In accordance with a first aspect, the coolant subsystem is separate from the feed to the processor reactor and is capable of circulating a coolant through the processor reactor. In accordance with a second aspect, the constituent elements of the fuel processor are housed in a cabinet, and the coolant subsystem is capable of cooling both the processor reactor and the interior of the cabinet. In various alternatives, the fuel processor can be employed to reform a fuel for a fuel cell power plant and/or may be used to provide thermal control for unrelated mechanical systems.
    Type: Grant
    Filed: September 30, 2004
    Date of Patent: February 21, 2012
    Assignee: Texaco Inc.
    Inventors: Hongqiao (Bruce) Sun, W. Spencer Wheat, Vesna R. Mirkovic, Daniel G. Casey
  • Patent number: 7988751
    Abstract: A method for controlling the purity of hydrogen in a reforming apparatus is described where in the apparatus includes a fuel processor, a purification unit and a system controller. The controller determines a calculated flow of reformate from the fuel processor and operates the purification unit based on the calculated flow. The calculated flow is derived from a process model of the fuel processor and known feed(s) to the fuel processor. The calculated flow of reformate is used to control the flow of reformate to adsorbent beds within the purification unit and can be used to control other materials flows within the apparatus. Means for reducing fluctuations in the pressure and/or flow rate of reformate flowing from the fuel processor to the purification unit are also disclosed. The purity of the hydrogen produced can be maintained by adjusting the operation of the purification unit in response to changes in reformate composition, pressure and/or flow rate.
    Type: Grant
    Filed: July 22, 2008
    Date of Patent: August 2, 2011
    Assignee: Texaco Inc.
    Inventors: W. Spencer Wheat, Hongqiao Sun, Bhaskar Balasubramanian, Vesna R. Mirkovic
  • Patent number: 7857875
    Abstract: A method for start-up and shut down of a fuel processor including an autothermal reformer employing a non-pyrophoric shift catalyst is disclosed. Also disclosed are a computer programmed to start-up or shut down a fuel processor including an autothermal reformer employing a non-pyrophoric shift catalyst or a program storage medium encoded with instruction that, when executed by a computer, start-up or shut down a fuel processor including an autothermal reformer employing a non-pyrophoric shift catalyst.
    Type: Grant
    Filed: May 11, 2006
    Date of Patent: December 28, 2010
    Assignee: Texaco Inc.
    Inventors: W. Spencer Wheat, Vesna R. Mirkovic, Kevin H. Nguyen, Curtis L. Krause, James F. Stevens, Daniel G. Casey
  • Patent number: 7785539
    Abstract: A method and apparatus for use in generating hydrogen are disclosed. The apparatus includes a fuel processor capable of producing a reformate from a fuel; a hydrogen purifier capable of generating a purified hydrogen gas stream from the reformate; a compressor capable of providing the reformate from the fuel processor to the pressure swing adsorption unit at a desired pressure; and a control system capable of integrating and controlling the operation of the fuel processor, the pressure swing adsorption unit, and the compressor. In another aspect, the invention includes a method for controlling the operation of a purified hydrogen generator, the method comprising: controlling the operation of a hydrogen generator; controlling the operation of a hydrogen purifier; and synchronizing the controlled operation of the hydrogen generator with the controlled operation of the hydrogen purifier.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: August 31, 2010
    Assignee: Texaco Inc.
    Inventors: Vesna R. Mirkovic, Hongqiao Sun, W. Spencer Wheat, Daniel G. Casey, Bhaskar Balasubramanian
  • Patent number: 7763087
    Abstract: An apparatus and a method for use in controlling the apparatus are disclosed. The apparatus includes a purified hydrogen generator; at least one of a compression unit, a storage unit, and a dispensing unit; and a system controller. The system controller is capable of monitoring the operation of the hydrogen generator and the compression unit, storage unit, or dispensing unit at a system level and shutting down at least one of hydrogen generator and the compression unit, storage unit, or dispensing unit upon the detection of a dangerous condition.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: July 27, 2010
    Assignee: Texaco Inc.
    Inventors: Masoud Hajiaghajani, Vesna R. Mirkovic, Hongqiao Sun, W. Spencer Wheat, Gregory W. Laframboise, Tonya A. Betts
  • Patent number: 7645307
    Abstract: A method and apparatus for use in controlling the reaction temperature of a fuel processor are disclosed. The apparatus includes a fuel processor reactor, the reactor including a water gas shift reaction section; a temperature sensor disposed within the reaction section; a coolant flow line through the reaction section; and an automated control system. The automated control system controls the reaction temperature by determining a first component for a setting adjustment for the actuator from the measured temperature and a setpoint for the measured temperature; determining a second component for the setting adjustment from a hydrogen production rate for the fuel processor; and determining the setting adjustment from the first and second components.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: January 12, 2010
    Assignee: Texaco Inc.
    Inventors: Hongqiao Sun, Daniel G. Casey, Vesna R. Mirkovic, Bhaskar Balasubramanian, W. Spencer Wheat
  • Patent number: 7593788
    Abstract: A method and apparatus for use in regenerating a reactor shift bed catalyst are disclosed. The method comprises monitoring the saturation level of a reactor shift bed catalyst in a reformer; automatically detecting that the reactor shift bed catalyst has entered a saturated state; and automatically regenerating the reactor shift bed catalyst in response to automatically detecting the saturated state. The apparatus may be, in various aspects, a program storage method encoded with instructions that, when executed by a computing device, performs such a method; a computing apparatus programmed to perform such a method, or a control system performing such a method.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: September 22, 2009
    Assignee: Texaco Inc.
    Inventors: Hongqiao Sun, Daniel G. Casey, Vesna R. Mirkovic, Bhaskar Balasubramanian, W. Spencer Wheat, Curtis L. Krause
  • Publication number: 20080289255
    Abstract: An apparatus and method for producing hydrogen. The apparatus includes a fuel processor, a purification unit and a system controller. The controller determines a calculated flow of reformate from the fuel processor and operates the purification unit based on the calculated flow. The calculated flow is derived from a process model of the fuel processor and known feed(s) to the fuel processor. The calculated flow of reformate is used to control the flow of reformate to adsorbent beds within the purification unit and can be used to control other materials flows within the apparatus. Means for reducing fluctuations in the pressure and/or flow rate of reformate flowing from the fuel processor to the purification unit are also disclosed. The purity of the hydrogen produced can be maintained by adjusting the operation of the purification unit in response to changes in reformate composition, pressure and/or flow rate.
    Type: Application
    Filed: July 22, 2008
    Publication date: November 27, 2008
    Applicant: Texaco Inc.
    Inventors: W. Spencer Wheat, Hongqiao Sun, Bhaskar Balasubramanian, Vesna R. Mirkovic
  • Patent number: 7410710
    Abstract: A method and apparatus for determining which condition in a fuel processor has initiated a shutdown of the fuel processor are disclosed. In general, the apparatus generates a plurality of shutdown initiator signals, each corresponding to one of a plurality of shutdown conditions and indicating whether such condition is present. The shutdown initiator signals are read within a predetermined window. At least one of the read shutdown initiator signals indicates that a corresponding first shutdown condition has occurred and identifies the corresponding first shutdown condition as the firstout.
    Type: Grant
    Filed: April 4, 2003
    Date of Patent: August 12, 2008
    Assignee: Texaco Inc.
    Inventors: Vesna R. Mirkovic, W. Spencer Wheat
  • Patent number: 7402287
    Abstract: An apparatus and method for producing hydrogen. The apparatus includes a fuel processor, a purification unit and a system controller. The controller determines a calculated flow of reformate from the fuel processor and operates the purification unit based on the calculated flow. The calculated flow is derived from a process model of the fuel processor and known feed(s) to the fuel processor. The calculated flow of reformate is used to control the flow of reformate to adsorbent beds within the purification unit and can be used to control other materials flows within the apparatus. Means for reducing fluctuations in the pressure and/or flow rate of reformate flowing from the fuel processor to the purification unit are also disclosed. The purity of the hydrogen produced can be maintained by adjusting the operation of the purification unit in response to changes in reformate composition, pressure and/or flow rate.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: July 22, 2008
    Assignee: Texaco Inc.
    Inventors: W. Spencer Wheat, Hongqiao Sun, Bhaskar Balasubramanian, Vesna R. Mirkovic
  • Publication number: 20080127554
    Abstract: An apparatus and method for producing a hydrogen-enriched reformate. The apparatus includes a fuel processor for converting a fuel to a reformate having fluctuations in pressure and or flow rate, means for reducing the fluctuations, a compression unit for compressing the reformate and one or more of a purification unit and a storage unit downstream of a compression unit. Means for reducing the fluctuations in the reformate can include one or more of a buffer and a conduit for providing a controlled flow of a supplemental fluid to an inlet of the compression unit. The supplemental fluid can include the compressed reformate, a hydrogen-enriched reformate, and mixtures thereof. The apparatus can include means for regulating power to the compression unit that can incrementally increase power to the compression unit particularly during start up. The purification unit can include one or more of a hydrogen selective membrane and a pressure swing adsorption unit. Methods for producing hydrogen are also disclosed.
    Type: Application
    Filed: February 7, 2008
    Publication date: June 5, 2008
    Applicant: Texaco Inc.
    Inventors: Dean A. Kenefake, W. Spencer Wheat, Hongqiao Sun, Bhaskar Balasubramanian, Vesna R. Mirkovic, Daniel G. Casey
  • Patent number: 7354464
    Abstract: An apparatus and method for producing a hydrogen-enriched reformate. The apparatus includes a fuel processor for converting a fuel to a reformate having fluctuations in pressure and or flow rate, means for reducing the fluctuations, a compression unit for compressing the reformate and one or more of a purification unit and a storage unit downstream of a compression unit. Means for reducing the fluctuations in the reformate can include one or more of a buffer and a conduit for providing a controlled flow of a supplemental fluid to an inlet of the compression unit. The supplemental fluid can include the compressed reformate, a hydrogen-enriched reformate, and mixtures thereof. The apparatus can include means for regulating power to the compression unit that can incrementally increase power to the compression unit particularly during start up. The purification unit can include one or more of a hydrogen selective membrane and a pressure swing adsorption unit. Methods for producing hydrogen are also disclosed.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: April 8, 2008
    Assignee: Texaco Inc.
    Inventors: Dean A. Kenefake, W. Spencer Wheat, Hongqiao Sun, Bhaskar Balasubramanian, Vesna R. Mirkovic, Daniel G. Casey
  • Patent number: 7354463
    Abstract: An apparatus and method for producing a hydrogen-enriched reformate. The apparatus includes a fuel processor for producing a reformate having fluctuations in a pressure and/or flow rate and means for reducing the fluctuations. The reformate comprises impurities that are removed by a purification unit having a plurality of adsorbent beds. A valve assembly controls the flow of reformate to the adsorbent beds based upon sensed product data generated by a product sensor. A compression unit optionally compresses the reformate prior to entering the purification unit. Means for reducing fluctuations in the pressure and/or flow rate include a buffer and/or a conduit for providing a controlled flow of a supplemental fluid to an inlet of the compression unit. A product valve can control the flow of hydrogen-enriched reformate out of the purification unit.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: April 8, 2008
    Assignee: Texaco Inc.
    Inventors: W. Spencer Wheat, Hongqiao Sun, Bhaskar Balasubramanian, Vesna R. Mirkovic
  • Patent number: 7318970
    Abstract: A control technique for use in a fuel processor is disclosed. In one aspect, a control system includes a subsystem manager controller the operation of a respective physical subsystem for each of a plurality of physical subsystems in the fuel processor. The subsystem managers take their direction from a master control manager. In a second aspect, the subsystem managers collectively form a layer operating in conjunction with a second layer capable of interfacing the subsystem managers to their respective physical subsystems, a third layer capable of interfacing the subsystem managers with the second layer. In a third aspect, master control manager manages the operation of each physical subsystem through a respective subsystem manager, directs state transitions of the subsystem managers, and routs interaction between the subsystem managers from the master control manager.
    Type: Grant
    Filed: April 4, 2003
    Date of Patent: January 15, 2008
    Assignee: Texaco Inc.
    Inventors: Vesna R. Mirkovic, W. Spencer Wheat, Hugh N. To, Dennis J. Benedetto
  • Patent number: 7266464
    Abstract: A method and apparatus are disclosed. The apparatus includes a store of at least one historical sensor measurement, a store of potential cut-off frequencies, and a filter. Each potential cut-off frequency is associated with a respective potential difference between a sensor measurement and the stored historical sensor measurement. The filter has a cut-off frequency dynamically selected from the stored potential cut-off frequencies on the basis of a difference between the stored historical sensor measurement and a current sensor measurement. The method includes determining a difference between a current sensor measurement and a historical sensor measurement; and dynamically selecting a cut-off frequency for a filter for the current sensor measurement from the difference.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: September 4, 2007
    Assignee: Texaco Inc.
    Inventors: Hongqiao Sun, Vesna R. Mirkovic, W. Spencer Wheat
  • Patent number: 7184847
    Abstract: A method and system are disclosed for controlling a process by establishing a control factor for a proportional-integral-derivative (PID) controller used to control a parameter of a process relative to a setpoint. A feedback signal regarding the parameter of the process is received via a sensor of the process and a first feedback loop. Automatic adjusting of the control factor of the PID controller is based on the feedback signal.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: February 27, 2007
    Assignee: Texaco Inc.
    Inventors: Hongqiao Sun, W. Spencer Wheat, Vesna R. Mirkovic
  • Patent number: 7081144
    Abstract: A method for start-up and shut down of a fuel processor including an autothermal reformer employing a non-pyrophoric shift catalyst is disclosed. Also disclosed are a computer programmed to start-up or shut down a fuel processor including an autothermal reformer employing a non-pyrophoric shift catalyst or a program storage medium encoded with instruction that, when executed by a computer, start-up or shut down a fuel processor including an autothermal reformer employing a non-pyrophoric shift catalyst.
    Type: Grant
    Filed: April 4, 2003
    Date of Patent: July 25, 2006
    Assignee: Texaco Inc.
    Inventors: W. Spencer Wheat, Vesna R. Mirkovic, Kevin H. Nguyen, Curtis L. Krause, James F. Stevens, Daniel G. Casey