Patents Assigned to Portland General Electric Corporation
  • Patent number: 5239441
    Abstract: A fault locating system for locating a fault in an underground power distribution system includes a method and an apparatus. The underground power distribution system receives and distributes power from a bulk power source to power consumers through a fused switchgear unit and a first vault. The first vault distributes power from the fused switchgear unit among plural outgoing underground power lines, with each line supplying power to at least one power consumer. A current limiting apparatus for locating faults in the above system includes an enclosure of an insulative material defining a fuse receiving chamber. First and second bushings extend through the enclosure to the fuse receiving chamber. The apparatus has a current limiting fuse received by the respective first and second bushings within the fuse receiving chamber.
    Type: Grant
    Filed: August 20, 1990
    Date of Patent: August 24, 1993
    Assignee: Portland General Electric Corporation
    Inventors: Larry D. Fox, Robert K. Flath
  • Patent number: 5220843
    Abstract: Without disassembling a valve stem from a valve, the valve is decoupled from a valve actuator such that the valve stem and attached valve disc or body may shift to and from a seated position without interference by the actuator. Known loads are applied to the decoupled valve stem to cause a strain gauge output which corresponds to the known load. The strain gauge is mounted to the valve stem or other force reactive components of the valve which react by changing in dimension in response to the applied known load. The relationship of the applied load to the strain gauge output is determined to thereby calibrate the valve stem. The load is removed and the valve stem is recoupled to the valve actuator for operation. From the strain gauge output during either or both static and dynamic operation of the valve, the thrust on the valve stem is directly obtained and is used to evaluate the performance of the valve and actuator.
    Type: Grant
    Filed: July 26, 1991
    Date of Patent: June 22, 1993
    Assignee: Portland General Electric Corporation
    Inventor: Thomas A. Rak