Patents by Inventor Christopher Douglas Schock

Christopher Douglas Schock 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).

  • System specific fluid flow control with induction motor drive
    Patent number: 6472843
    Abstract: An apparatus and method for controlling a motor/blower system to provide a constant fluid flow by iteratively loading revised stator frequency values and stator voltage values to a variable frequency drive. Target DC bus current values corresponding to constant fluid flow rates are predetermined and stored as a function of the desired fluid flow rate, the operating frequency, and system specific constants or calculated by the controller as a function thereof during system operation. Actual DC bus current is measured with a current sensor and compared with the target DC bus current. Operating frequency is estimated using a PI controller based on the difference between measured and target DC bus current values. Operating voltage values corresponding to operating frequencies and system specific constants are predetermined and stored in memory or calculated by the controller during system operation. An updated target DC bus current, operating frequency and operating voltage are determined upon each iteration.
    Type: Grant
    Filed: January 18, 2001
    Date of Patent: October 29, 2002
    Assignee: Fasco Industries, Inc.
    Inventors: Michael D. Smith, Thien Q. Tran, Christopher Douglas Schock, James R. Peterson, Parimalalagan Ramachandran
  • System specific fluid flow control with induction motor drive
    Publication number: 20010033147
    Abstract: An apparatus and method for controlling a motor/blower system to provide a constant fluid flow by iteratively loading revised stator frequency values and stator voltage values to a variable frequency drive. Target DC bus current values corresponding to constant fluid flow rates are predetermined and stored as a function of the desired fluid flow rate, the operating frequency, and system specific constants or calculated by the controller as a function thereof during system operation. Actual DC bus current is measured with a current sensor and compared with the target DC bus current. Operating frequency is estimated using a PI controller based on the difference between measured and target DC bus current values. Operating voltage values corresponding to operating frequencies and system specific constants are predetermined and stored in memory or calculated by the controller during system operation. An updated target DC bus current, operating frequency and operating voltage are determined upon each iteration.
    Type: Application
    Filed: January 18, 2001
    Publication date: October 25, 2001
    Inventors: Michael D. Smith, Thien Q. Tran, Christopher Douglas Schock, James R. Peterson, Parimelalagan Ramachandran