Patents by Inventor Venkatapathi Nallapa

Venkatapathi Nallapa 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).

  • Publication number: 20070016340
    Abstract: A control system, method and article allows a monitoring module to monitor operation of a main controller in an electric drive, by providing questions and evaluating the accuracy and/or timeliness of responses from the main controller. Upon detection of an excessive number of incorrect or late responses, the monitoring module can shutdown operation, and may provide an alternative communications path, thereby preventing corrupt data from reaching a vehicle network, while providing communications for diagnostic and recovery such as by provision of new software or firmware instructions. The main controller may monitor the operation of the monitoring module, taking appropriate action if a fault is detected. Disabling a supply of power to a traction motor may be based on current operating conditions, such as speed.
    Type: Application
    Filed: June 29, 2006
    Publication date: January 18, 2007
    Inventors: Christophe Soudier, Bing Cheng, Steven Kowalec, Venkatapathi Nallapa, Richard Hampo
  • Publication number: 20060119306
    Abstract: A system, method, and article for protecting a power source for a machine from sudden changes in load. In one embodiment, energy is wasted in a winding of a motor in response to a decrease in a load presented to the power source.
    Type: Application
    Filed: December 3, 2004
    Publication date: June 8, 2006
    Inventors: Richard Hampo, Venkatapathi Nallapa, Franz Prenner
  • Publication number: 20060021358
    Abstract: A system and method for detecting failure of a cooling system in an alternating current machine, such as a motor and/or a generator. For example, in one embodiment energy wasting is initiated and a failure is indicated if a temperature rises by more than a selected amount over a selected time period.
    Type: Application
    Filed: December 3, 2004
    Publication date: February 2, 2006
    Inventor: Venkatapathi Nallapa
  • Publication number: 20060021450
    Abstract: An encoder failure detector system and method for detecting failure of an encoder at near-zero rotational speeds. For example, in one embodiment a failure is indicated if a torque command exceeds a selected threshold for a selected period of time and no movement of a rotor is detected during the selected period of time.
    Type: Application
    Filed: July 30, 2004
    Publication date: February 2, 2006
    Inventor: Venkatapathi Nallapa
  • Publication number: 20060022625
    Abstract: A control subsystem for an electric motor determines whether power was interrupted, and delays torque production if power was interrupted. The control subsystem may employ two separate non-volatile memory locations, or alternatively a single non-volatile memory location.
    Type: Application
    Filed: July 30, 2004
    Publication date: February 2, 2006
    Inventors: Richard Hampo, Venkatapathi Nallapa, Christophe Soudier
  • Publication number: 20050253543
    Abstract: A torque current peak compensation value is subtracted from a torque current reference value, where the torque current peak compensation value is based at least in part on a determined peak of vibration. A torque current compensation value is subtracted from the results to produce an adjusted torque current reference value.
    Type: Application
    Filed: March 30, 2005
    Publication date: November 17, 2005
    Inventors: Christophe Soudier, Richard Hampo, Vinod Reddy, Venkatapathi Nallapa
  • Publication number: 20050254273
    Abstract: A controller implements a state machine for operating the bidirectional power converter with a flexible load pattern while maintaining a thermal condition of the power converter within acceptable limits. The state machine implements a wait loop in response to selected conditions to maintain the thermal condition.
    Type: Application
    Filed: March 30, 2005
    Publication date: November 17, 2005
    Inventors: Christophe Soudier, Lizhi Zhu, Vinod Reddy, Venkatapathi Nallapa
  • Publication number: 20050055496
    Abstract: An efficient emulation of EEPROM employing flash memory employs a fixed location for an address pointer in flash memory and such that an erase operation is required only once every nth update where n is the number of bits at the fixed location, thus avoiding the need to erase the sector on every update and avoiding delays associated with linked lists for determining the address of the most up-to-date information. Use of bit shifting provides fast determination of the desired address.
    Type: Application
    Filed: September 9, 2003
    Publication date: March 10, 2005
    Applicant: Ballard Power Systems Corporation
    Inventor: Venkatapathi Nallapa