Patents by Inventor Sayeed Ahmed

Sayeed 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).

  • Patent number: 7046535
    Abstract: Power converters such as power modules configured as inverters employ modularized approaches. In some aspects, semiconductor devices are thermally coupled directly to thermally conductive substrates without intervening dielectric or insulative structures. Additionally, or alternatively, semiconductor devices are thermally coupled to thermally conductive substrates with relatively large surface areas before heat transferred from the semiconductor devices encounters a dielectric or electrically insulating structure with correspondingly high thermal impedance.
    Type: Grant
    Filed: December 3, 2004
    Date of Patent: May 16, 2006
    Assignee: Ballard Power Systems Corporation
    Inventors: Pablo Rodriguez, Douglas K. Maly, Ajay V. Patwardhan, Kanghua Chen, Sayeed Ahmed, Gerardo Jimenez, Fred Flett
  • Publication number: 20060082983
    Abstract: A DC bus for use in a power module has a positive DC conductor bus plate parallel with a negative DC conductor bus plate. One or more positive leads are connected to the positive bus and are connectable to a positive terminal of a power source. One or more negative leads are connected to the negative bus and are connectable to a negative terminal of a power source. The DC bus has one or more positive connections fastenable from the positive bus to the high side of a power module. The DC bus also has one or more negative connections fastenable from the negative bus to the low side of the power module. The positive bus and negative bus permit counter-flow of currents, thereby canceling magnetic fields and their associated inductances, and the positive and negative bus are connectable to the center portion of a power module.
    Type: Application
    Filed: December 2, 2005
    Publication date: April 20, 2006
    Inventors: Scott Parkhill, Sayeed Ahmed, Fred Flett
  • Publication number: 20060062023
    Abstract: A power converter comprising a DC/AC bridge circuit electrically coupled between positive and negative DC bus terminals and a set of phase terminals, a DC/DC bridge circuit electrically coupled to the positive and negative DC bus terminals and a set of DC bridge terminals. The power converter may be configured to control the transfer of power to and/or from the DC bridge terminals and to control the transfer of power to and/or from the AC phase terminals.
    Type: Application
    Filed: September 21, 2004
    Publication date: March 23, 2006
    Inventors: Ajay Patwardhan, Douglas Maly, Fred Flett, Sayeed Ahmed, Pablo Rodriguez, Kanghua Chen, Gerardo Jimenez
  • Patent number: 7012810
    Abstract: A DC bus for use in a power module has a positive DC conductor bus plate parallel with a negative DC conductor bus plate. One or more positive leads are connected to the positive bus and are connectable to a positive terminal of a power source. One or more negative leads are connected to the negative bus and are connectable to a negative terminal of a power source. The DC bus has one or more positive connections fastenable from the positive bus to the high side of a power module. The DC bus also has one or more negative connections fastenable from the negative bus to the low side of the power module. The positive bus and negative bus permit counter-flow of currents, thereby canceling magnetic fields and their associated inductances, and the positive and negative bus are connectable to the center portion of a power module.
    Type: Grant
    Filed: March 27, 2002
    Date of Patent: March 14, 2006
    Assignee: Ballard Power Systems Corporation
    Inventors: Scott Parkhill, Sayeed Ahmed, Fred Flett
  • Publication number: 20060028806
    Abstract: A DC bus for use in a power module has a positive DC conductor bus plate parallel with a negative DC conductor bus plate. One or more positive leads are connected to the positive bus and are connectable to a positive terminal of a power source. One or more negative leads are connected to the negative bus and are connectable to a negative terminal of a power source. The DC bus has one or more positive connections fastenable from the positive bus to the high side of a power module. The DC bus also has one or more negative connections fastenable from the negative bus to the low side of the power module. The positive bus and negative bus permit counter-flow of currents, thereby canceling magnetic fields and their associated inductances, and the positive and negative bus are connectable to the center portion of a power module.
    Type: Application
    Filed: October 6, 2005
    Publication date: February 9, 2006
    Inventors: Scott Parkhill, Sayeed Ahmed, Fred Flett
  • Patent number: 6987670
    Abstract: A dual power module architecture employing a high degree of modularity, that allows a base power module to be quickly, easily, and cost effectively configured to address a large variety of applications.
    Type: Grant
    Filed: August 14, 2003
    Date of Patent: January 17, 2006
    Assignee: Ballard Power Systems Corporation
    Inventors: Sayeed Ahmed, Fred Flett, Ajay V. Patwardhan, Douglas K. Maly
  • Publication number: 20060007721
    Abstract: Power converters such as power modules configured as inverters employ modularized approaches. In some aspects, semiconductor devices are thermally coupled directly to thermally conductive substrates without intervening dielectric or insulative structures. Additionally, or alternatively, semiconductor devices are thermally coupled to thermally conductive substrates with relatively large surface areas before heat transferred from the semiconductor devices encounters a dielectric or electrically insulating structure with correspondingly high thermal impedance.
    Type: Application
    Filed: December 13, 2004
    Publication date: January 12, 2006
    Inventors: Pablo Rodriguez, Douglas Maly, Ajay Patwardhan, Kanghua Chen, Sayeed Ahmed, Gerardo Jimenez, Fred Flett
  • Publication number: 20050270745
    Abstract: A power converter integrates at least one planar transformer comprising a multi-layer transformer substrate and/or at least one planar inductor comprising a multi-layer inductor substrate with a number of power semiconductor switches physically and thermally coupled to a heat sink via one or more multi-layer switch substrates.
    Type: Application
    Filed: October 12, 2004
    Publication date: December 8, 2005
    Inventors: Kanghua Chen, Sayeed Ahmed, Lizhi Zhu
  • Publication number: 20050162875
    Abstract: Power converters such as power modules configured as inverters employ modularized approaches. In some aspects, semiconductor devices are thermally coupled directly to thermally conductive substrates without intervening dielectric or insulative structures. Additionally, or alternatively, semiconductor devices are thermally coupled to thermally conductive substrates with relatively large surface areas before heat transferred from the semiconductor devices encounters a dielectric or electrically insulating structure with correspondingly high thermal impedance.
    Type: Application
    Filed: December 13, 2004
    Publication date: July 28, 2005
    Inventors: Pablo Rodriguez, Douglas Maly, Ajay Patwardhan, Kanghua Chen, Sayeed Ahmed, Gerardo Jimenez, Fred Flett
  • Publication number: 20050152101
    Abstract: Power converters such as power modules configured as inverters employ modularized approaches. In some aspects, semiconductor devices are thermally coupled directly to thermally conductive substrates without intervening dielectric or insulative structures. Additionally, or alternatively, semiconductor devices are thermally coupled to thermally conductive substrates with relatively large surface areas before heat transferred from the semiconductor devices encounters a dielectric or electrically insulating structure with correspondingly high thermal impedance.
    Type: Application
    Filed: December 13, 2004
    Publication date: July 14, 2005
    Inventors: Pablo Rodriguez, Douglas Maly, Ajay Patwardhan, Kanghua Chen, Sayeed Ahmed, Gerardo Jimenez, Fred Flett
  • Publication number: 20050152100
    Abstract: Power converters such as power modules configured as inverters employ modularized approaches. In some aspects, semiconductor devices are thermally coupled directly to thermally conductive substrates without intervening dielectric or insulative structures. Additionally, or alternatively, semiconductor devices are thermally coupled to thermally conductive substrates with relatively large surface areas before heat transferred from the semiconductor devices encounters a dielectric or electrically insulating structure with correspondingly high thermal impedance.
    Type: Application
    Filed: December 3, 2004
    Publication date: July 14, 2005
    Inventors: Pablo Rodriguez, Douglas Maly, Ajay Patwardhan, Kanghua Chen, Sayeed Ahmed, Gerardo Jimenez, Fred Flett
  • Patent number: 6914354
    Abstract: Methods and related systems providing removal of heat from electric motors via fluid baths.
    Type: Grant
    Filed: December 30, 2002
    Date of Patent: July 5, 2005
    Assignee: Ballard Power Systems Corporation
    Inventors: David Seniawski, Jason M. Cardinal, Sayeed Ahmed
  • Publication number: 20050128706
    Abstract: A power module comprises first and second substrates carrying semiconductor devices and coupled to respective pluralities of heat exchange members without intervening thermally insulative structures. One or more heat exchange loops circulate a heat exchange medium thermally coupled to the heat exchange members. Substrates may function as integral bus bars.
    Type: Application
    Filed: December 16, 2003
    Publication date: June 16, 2005
    Applicant: Ballard Power Systems Corporation
    Inventors: Douglas Maly, Kanghua Chen, Ajay Patwardhan, Sayeed Ahmed, Pablo Rodriguez, Gerardo Jimenez
  • Patent number: 6906404
    Abstract: A power module employs at least one capacitor electrically coupled across the input terminals to reduce voltage overshoot. The capacitor may be surface mounted to a high side collector plating area and a low side emitter plating area. The power module may employ a lead frame and terminals accessible from an exterior of a module housing, for making electrical couplings to externally located power sources and/or loads.
    Type: Grant
    Filed: August 14, 2003
    Date of Patent: June 14, 2005
    Assignee: Ballard Power Systems Corporation
    Inventors: Douglas K. Maly, Sayeed Ahmed, Ajay V. Patwardhan, Fred Flett
  • Patent number: 6845017
    Abstract: A DC bus for use in a power module includes a positive DC conductor bus plate parallel with a negative DC conductor bus plate. The positive bus and negative bus permit counter-flow of currents, thereby canceling magnetic fields and their associated inductances, and the positive and negative bus are connectable to the center portion of a power module.
    Type: Grant
    Filed: September 20, 2001
    Date of Patent: January 18, 2005
    Assignee: Ballard Power Systems Corporation
    Inventors: Sayeed Ahmed, Scott Parkhill, Fred Flett, Douglas Maly
  • Publication number: 20040228094
    Abstract: A dual power module architecture employing a high degree of modularity, that allows a base power module to be quickly, easily, and cost effectively configured to address a large variety of applications.
    Type: Application
    Filed: August 14, 2003
    Publication date: November 18, 2004
    Applicant: Ballard Power Systems Corporation
    Inventors: Sayeed Ahmed, Fred Flett, Ajay V. Patwardhan, Douglas K. Maly
  • Publication number: 20040227231
    Abstract: A power module employs at least one capacitor electrically coupled across the input terminals to reduce voltage overshoot. The capacitor may be surface mounted to a high side collector plating area and a low side emitter plating area.
    Type: Application
    Filed: August 14, 2003
    Publication date: November 18, 2004
    Applicant: Ballard Power Systems Corporation
    Inventors: Douglas K. Maly, Sayeed Ahmed, Ajay V. Patwardhan, Fred Flett
  • Publication number: 20040230847
    Abstract: A power converter utilizes a high frequency capacitor and a bulk capacitor coupled across the DC terminals to reduce high frequency effect and voltage overshoot, leading to space and cost savings in power converter design. Each capacitor may be physically coupled adjacent the gate driver board via clips, clamps, and/or fasteners.
    Type: Application
    Filed: September 17, 2003
    Publication date: November 18, 2004
    Applicant: Ballard Power Systems Corporation
    Inventors: Ajay V. Patwardhan, Douglas K. Maly, Sayeed Ahmed, Fred Flett
  • Patent number: 6793502
    Abstract: An electrical connector for use in a power module includes a first end portion for forming an electrical connection with a substrate, a second end portion, and a compliant portion situated between the first end portion and the second end portion. The compliant portion includes a compressed position and a decompressed position. The first end portion is configured for forming an electrical connection with a substrate if the compliant portion is in the compressed position.
    Type: Grant
    Filed: September 20, 2001
    Date of Patent: September 21, 2004
    Assignee: Ballard Power Systems Corporation
    Inventors: Scott Parkhill, Sayeed Ahmed, Fred Flett
  • Patent number: 6639334
    Abstract: An assembly for cooling an electric motor, the assembly comprising a housing, a stator, a rotor, a winding, an end-winding integrally formed with the winding, and a jet impingement device operable for exposing the end-winding to a temperature controlled stream of fluid. A method for transferring heat between a stream of impinging fluid and the surface of an electric motor end-winding. An electric motor comprising a jet impingement cooling assembly.
    Type: Grant
    Filed: November 30, 2001
    Date of Patent: October 28, 2003
    Assignee: Ballard Power Systems Corporation
    Inventors: Kanghua Chen, Abul Masrur, Sayeed Ahmed, Vijay K Garg