Patents by Inventor Thomas Keister

Thomas Keister 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: 8601190
    Abstract: A control system may be provided for a controlled system such as a drive or inverter system. To provide for control in such system, a master controller may be present to receive, via a second communication protocol from a cabinet controller coupled to the master controller, status information of a controlled device, generate control information based at least in part on the status information, and transmit the control information to the cabinet controller via the second communication protocol. In turn, the cabinet controller can generate and communicate a control packet to the controlled device via a first communication protocol. This packet can be interleaved within another message communicated from the cabinet controller to the device.
    Type: Grant
    Filed: June 24, 2011
    Date of Patent: December 3, 2013
    Assignee: TECO-Westinghouse Motor Company
    Inventors: Randall Pipho, Ryan Edwards, Mehdi Abolhassani, Enrique Ledezma, Alex Skorcz, Thomas Keister
  • Publication number: 20120327602
    Abstract: In an embodiment, a medium voltage drive system includes a transformer, multiple power cubes each coupled to the transformer, and a manifold assembly. Each power cube includes cold plates each coupled to a corresponding switching device of the cube, an inlet port in communication with a first one of the cold plates and an outlet port in communication with a last one of the cold plates. The manifold assembly can support an inlet conduit and an outlet conduit and further support first and second connection members to enable blind mating of each of the first connection members to the inlet port of one of the power cubes and each of the second connection members to the outlet port of one of the power cubes to enable two phase cooling of the plurality of power cubes.
    Type: Application
    Filed: September 7, 2012
    Publication date: December 27, 2012
    Inventors: Devdatta P. Kulkarni, Thomas Keister, Manzoor Hussain, Scott Simmons, UT V. Pham, Rose Craft, Randall Pipho
  • Publication number: 20120331195
    Abstract: A control system may be provided for a controlled system such as a drive or inverter system. To provide for control in such system, a master controller may be present to receive, via a second communication protocol from a cabinet controller coupled to the master controller, status information of a controlled device, generate control information based at least in part on the status information, and transmit the control information to the cabinet controller via the second communication protocol. In turn, the cabinet controller can generate and communicate a control packet to the controlled device via a first communication protocol. This packet can be interleaved within another message communicated from the cabinet controller to the device.
    Type: Application
    Filed: June 24, 2011
    Publication date: December 27, 2012
    Inventors: Randall Pipho, Ryan Edwards, Mehdi Abolhassani, Enrique Ledezma, Alex Skorcz, Thomas Keister
  • Patent number: 8279640
    Abstract: In one embodiment, a system may include multiple transformers each to provide an output to one or more power cells, where the power cells provide AC power to a load. Each transformer may have at least one primary winding and multiple secondary windings, where the primary winding of each transformer is phase shifted with respect to its neighboring transformers and the secondary windings are also phase shifted. The phase shift of the primary winding can be based on the phase shift of the secondary windings and a number of the plurality of transformers.
    Type: Grant
    Filed: September 24, 2008
    Date of Patent: October 2, 2012
    Assignee: TECO-Westinghouse Motor Company
    Inventors: Mehdi Abolhassani, Ryan Edwards, Thomas Keister, Alex Skorcz, Enrique Ledezma, Chao Hsu Liao
  • Patent number: 8254076
    Abstract: In one embodiment, a medium voltage drive system includes at least one transformer and multiple power cell chambers each coupled to a transformer. The power cell chambers each may include a rectifier, a DC-link, and an inverter. Each power cell chamber can be separated into fixed and moveable portions, where the moveable portion includes the rectifier and the inverter and the fixed portion includes the DC-link. A power service bus can couple the fixed and moveable portions of each power cell chamber and couple in series groups of the plurality of power cell chambers.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: August 28, 2012
    Assignee: TECO-Westinghouse Motor Company
    Inventors: Enrique Ledezma, Thomas Keister, Mehdi Abolhassani, Ryan Edwards, Alex Skorcz, Randall Pipho, Srinivas Satumahanti
  • Patent number: 8223515
    Abstract: A transformer module includes a main primary winding coupled to a first input power source to receive a medium voltage signal, multiple main secondary windings each to couple to a power cell of a drive system, and an auxiliary primary winding coupled to a second input power source to receive a low voltage signal. The auxiliary primary winding can be spatially separated from the main windings to increase leakage inductance. The auxiliary primary winding can be active during a pre-charge operation to pre-charge the power cells.
    Type: Grant
    Filed: February 26, 2009
    Date of Patent: July 17, 2012
    Assignee: TECO—Westinghouse Motor Company
    Inventors: Mehdi Abolhassani, Thomas Keister, Alex Skorcz, Ryan Edwards, Enrique Ledezma
  • Patent number: 8213198
    Abstract: In one embodiment, the present invention includes a medium voltage drive system having multiple power cells each to couple between a transformer and a load. A first subset of the power cells are configured to provide power to the load and to perform partial regeneration from the load, and a second subset of the power cells are configured to provide power to the load but not perform partial regeneration. A controller may be included in the system to simultaneously control a DC bus voltage of at least one of the first subset of the power cells, correct a power factor of the system, and provide harmonic current compensation for the system.
    Type: Grant
    Filed: April 27, 2011
    Date of Patent: July 3, 2012
    Assignee: TECO-Westinghouse Motor Company
    Inventors: Mehdi Abolhassani, Thomas Keister, Alex Skorcz, Enrique Ledezma, Ryan Edwards
  • Publication number: 20120127673
    Abstract: In one embodiment, a power cell chamber for a drive system includes moveable and fixed portions. The moveable portion includes a rectifier stage to rectify an input signal received from a secondary winding of a transformer to provide a rectified signal and an inverter stage having a plurality of switching devices to receive a DC signal and output an AC signal. This moveable portion can be slidably adapted within a cabinet of the drive system. In turn, the fixed portion includes a DC link having at least one capacitor to receive the rectified signal and provide the DC signal to the inverter stage.
    Type: Application
    Filed: January 31, 2012
    Publication date: May 24, 2012
    Inventors: Enrique Ledezma, Thomas Keister, Mehdi Abolhassani, Ryan Edwards, Alex Skorcz, Randall Pipho, Srinivas Satumahanti
  • Patent number: 8130501
    Abstract: In one embodiment, a power cell chamber for a drive system includes moveable and fixed portions. The moveable portion includes a rectifier stage to rectify an input signal received from a secondary winding of a transformer to provide a rectified signal and an inverter stage having a plurality of switching devices to receive a DC signal and output an AC signal. This moveable portion can be slidably adapted within a cabinet of the drive system. In turn, the fixed portion includes a DC link having at least one capacitor to receive the rectified signal and provide the DC signal to the inverter stage.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: March 6, 2012
    Assignee: TECO-Westinghouse Motor Company
    Inventors: Enrique Ledezma, Thomas Keister, Mehdi Abolhassani, Ryan Edwards, Alex Skorcz, Randall Pipho, Srinivas Satumahanti
  • Patent number: 8129853
    Abstract: In one embodiment, the present invention includes a turbine to generate mechanical energy from kinetic energy, a generator coupled to the turbine to receive the mechanical energy and to output multiple isolated supply powers, and multiple power stages each coupled to the generator. Each of the power stages may receive at least one of the isolated supply powers.
    Type: Grant
    Filed: June 30, 2010
    Date of Patent: March 6, 2012
    Assignee: TECO-Westinghouse Motor Company
    Inventors: Mehdi Abolhassani, Thomas Keister, Haran Karmaker, Ryan Edwards, Enrique Ledezma, Alex Skorcz
  • Patent number: 8106526
    Abstract: In one embodiment, the present invention includes a turbine to generate mechanical energy from kinetic energy, a generator coupled to the turbine to receive the mechanical energy and to output multiple isolated supply powers, and multiple power stages each coupled to the generator. Each of the power stages may receive at least one of the isolated supply powers.
    Type: Grant
    Filed: June 30, 2010
    Date of Patent: January 31, 2012
    Assignee: TECO-Westinghouse Motor Company
    Inventors: Mehdi Abolhassani, Thomas Keister, Haran Karmaker, Ryan Edwards, Enrique Ledezma, Alex Skorcz
  • Patent number: 8045346
    Abstract: In one embodiment, the present invention includes a system having multiple modular transformers each including a primary winding coupled to an input power source and phase-shifted secondary windings each coupled to a power cell. The system further includes different phase output lines coupled to a load. These lines may include first, second and third phase output lines.
    Type: Grant
    Filed: September 27, 2010
    Date of Patent: October 25, 2011
    Assignee: TECO-Westinghouse Motor Company
    Inventors: Mehdi Abolhassani, Ryan Edwards, Thomas Keister, Alex Skorcz, Enrique Ledezma, Chao Hsu Liao
  • Publication number: 20110199033
    Abstract: In one embodiment, the present invention includes a medium voltage drive system having multiple power cells each to couple between a transformer and a load. A first subset of the power cells are configured to provide power to the load and to perform partial regeneration from the load, and a second subset of the power cells are configured to provide power to the load but not perform partial regeneration. A controller may be included in the system to simultaneously control a DC bus voltage of at least one of the first subset of the power cells, correct a power factor of the system, and provide harmonic current compensation for the system.
    Type: Application
    Filed: April 27, 2011
    Publication date: August 18, 2011
    Inventors: Mehdi Abolhassani, Thomas Keister, Alex Skorcz, Enrique Ledezma, Ryan Edwards
  • Patent number: 7940537
    Abstract: In one embodiment, the present invention includes a medium voltage drive system having multiple power cells each to couple between a transformer and a load. A first subset of the power cells are configured to provide power to the load and to perform partial regeneration from the load, and a second subset of the power cells are configured to provide power to the load but not perform partial regeneration. A controller may be included in the system to simultaneously control a DC bus voltage of at least one of the first subset of the power cells, correct a power factor of the system, and provide harmonic current compensation for the system.
    Type: Grant
    Filed: December 31, 2008
    Date of Patent: May 10, 2011
    Assignee: TECO-Westinghouse Motor Company
    Inventors: Mehdi Abolhassani, Thomas Keister, Alex Skorcz, Enrique Ledezma, Ryan Edwards
  • Publication number: 20110044010
    Abstract: In one embodiment, a power cell chamber for a drive system includes moveable and fixed portions. The moveable portion includes a rectifier stage to rectify an input signal received from a secondary winding of a transformer to provide a rectified signal and an inverter stage having a plurality of switching devices to receive a DC signal and output an AC signal. This moveable portion can be slidably adapted within a cabinet of the drive system. In turn, the fixed portion includes a DC link having at least one capacitor to receive the rectified signal and provide the DC signal to the inverter stage.
    Type: Application
    Filed: July 28, 2010
    Publication date: February 24, 2011
    Inventors: Enrique Ledezma, Thomas Keister, Mehdi Abolhassani, Ryan Edwards, Alex Skorcz, Randall Pipho, Srinivas Satumahanti
  • Publication number: 20110013428
    Abstract: In one embodiment, the present invention includes a system having multiple modular transformers each including a primary winding coupled to an input power source and phase-shifted secondary windings each coupled to a power cell. The system further includes different phase output lines coupled to a load. These lines may include first, second and third phase output lines.
    Type: Application
    Filed: September 27, 2010
    Publication date: January 20, 2011
    Inventors: MEHDI ABOLHASSANI, Ryan Edwards, Thomas Keister, Alex Skorcz, Enrique Ledezma, Chao Hsu Liao
  • Publication number: 20110012364
    Abstract: In one embodiment, the present invention includes a turbine to generate mechanical energy from kinetic energy, a generator coupled to the turbine to receive the mechanical energy and to output multiple isolated supply powers, and multiple power stages each coupled to the generator. Each of the power stages may receive at least one of the isolated supply powers.
    Type: Application
    Filed: June 30, 2010
    Publication date: January 20, 2011
    Inventors: MEHDI ABOLHASSANI, Thomas Keister, Haran Karmaker, Ryan Edwards, Enrique Ledezma, Alex Skorcz
  • Patent number: 7863766
    Abstract: In one embodiment, the present invention includes a turbine to generate mechanical energy from kinetic energy, a generator coupled to the turbine to receive the mechanical energy and to output multiple isolated supply powers, and multiple power stages each coupled to the generator. Each of the power stages may receive at least one of the isolated supply powers.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: January 4, 2011
    Assignee: TECO-Westinghouse Motor Company
    Inventors: Mehdi Abolhassani, Thomas Keister, Haran Karmaker, Ryan Edwards, Enrique Ledezma, Alex Skorcz
  • Publication number: 20100328883
    Abstract: In one embodiment, a power cell chamber for a drive system includes moveable and fixed portions. The moveable portion includes a rectifier stage to rectify an input signal received from a secondary winding of a transformer to provide a rectified signal and an inverter stage having a plurality of switching devices to receive a DC signal and output an AC signal. This moveable portion can be slidably adapted within a cabinet of the drive system. In turn, the fixed portion includes a DC link having at least one capacitor to receive the rectified signal and provide the DC signal to the inverter stage.
    Type: Application
    Filed: June 30, 2009
    Publication date: December 30, 2010
    Inventors: Enrique Ledezma, Thomas Keister, Mehdi Abolhassani, Ryan Edwards, Alex Skorcz, Randall Pipho, Srinivas Satumahanti
  • Publication number: 20100327666
    Abstract: In one embodiment, the present invention includes a turbine to generate mechanical energy from kinetic energy, a generator coupled to the turbine to receive the mechanical energy and to output multiple isolated supply powers, and multiple power stages each coupled to the generator. Each of the power stages may receive at least one of the isolated supply powers.
    Type: Application
    Filed: June 30, 2010
    Publication date: December 30, 2010
    Inventors: Mehdi Abolhassani, Thomas Keister, Haran Karmaker, Ryan Edwards, Enrique Ledezma, Alex Skorcz