Patents Assigned to Electric Power Research Institute, Inc.
  • Patent number: 5857322
    Abstract: An electric power generation system combines a gas turbine generator with a solar power plant and utilizes the gas turbine exhaust for steam superheating and feed water heating only. The solar heater is only utilized for boiling or evaporation of feed water into steam, the feed water having previously been heated by a downstream portion of the turbine exhaust. In order to balance the disparity between the specific heats of water and steam to thus optimize the system, the steam is superheated by an upstream portion of the turbine exhaust to first drive a high pressure steam turbine and then reheated by the same exhaust over the same temperature range to drive a low pressure steam turbine.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: January 12, 1999
    Assignee: Electric Power Research Institute, Inc.
    Inventor: Arthur Cohn
  • Patent number: 5854173
    Abstract: A method for removing vapor phase contaminants from a gas stream. Sorbent particles are injected into the gas stream to react with vapor phase contaminants in the gas stream. Each sorbent particle is made from a support particle of a material coated with a layer of sorbent material different than the material of the support particle. The gas stream is directed through a particulate control device to remove the sorbent particles from the gas stream. A sorbent particle for use in the method and a method for manufacture of the sorbent particle are provided.
    Type: Grant
    Filed: May 31, 1996
    Date of Patent: December 29, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventors: Ramsay Chang, Massoud Rostam-Abadi
  • Patent number: 5851033
    Abstract: A corrosion limiting device for use with a fluid-carrying piping system having a connection formed from first and second components. A seal is carried by the components for forming a fluid-tight seal between the components. The components form a groove external of the seal. The corrosion limiting device includes an elongate member having first and second end portions and a length sufficient to extend around the groove. At least a portion of the elongate member is adapted to seat within the groove for aligning the elongate member on the components. The first and second end portions of the elongate member are fastened together. The elongate member serves to inhibit corrosion of the connection.
    Type: Grant
    Filed: April 30, 1997
    Date of Patent: December 22, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventors: E. Stephen Hunt, John M. Jenco
  • Patent number: 5845479
    Abstract: A combustion turbine power generation system includes a modified simple cycle combustion turbine power generation system optimized for a "hot" stand-by reserve mode of operation and having a power shaft assembly including a compressor, an expansion turbine, and a double-ended motor/generator between the compressor and the turbine. The motor/generator has a turbine driving clutch structure on one end thereof and a compressor driving clutch structure on the other end thereof. A combustor feeds the expansion turbine. The power generation system includes an additional system having a boost compressor, an intercooler feeding cooled air to the boost compressor an electric motor for driving the boost compressor, and aftercooler downstream of the boost compressor. A compressed air energy storage is downstream of the aftercooler.
    Type: Grant
    Filed: January 20, 1998
    Date of Patent: December 8, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventors: Michael Nakhamkin, Robert Schainker
  • Patent number: 5841644
    Abstract: A passively clamped quasi-resonant DC link ("PCQRL") converter includes an output inverter having a plurality of switches, and a DC link between a DC power source and the output inverter. The DC link is realized by a clamp transformer having a clamp factor not higher than 1.1-1.3 and a small auxiliary inductance which is switched by a pair of auxiliary switches (driven by the same gating signal) and a pair of diodes. When the auxiliary switches are turned "ON", the DC link voltage drops to zero; and the switches of the output inverter then can be switched under zero voltage condition with no switching losses. Most of the modulation schemes, including PWM, are applicable to the DC link design.
    Type: Grant
    Filed: September 4, 1996
    Date of Patent: November 24, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventors: Thomas A. Lipo, Shaotang Chen
  • Patent number: 5838881
    Abstract: An intelligent controller for on-line monitoring of circulation system in order to minimize a problem of streaming electrification and to avoid degradation of the electrical insulation of the system. The controller is designed to combine advantages of fuzzy logic and neural networks, and includes a fuzzy logic (employing a pseudo-neural network) for acquiring analog input data from a plurality of sensors and for interpreting this input data into fuzzyfier outputs. A main processor consisting of a fully connected feed-forward neural network serves for processing the fuzzifier outputs in order to obtain controlling instructions for the system.
    Type: Grant
    Filed: July 14, 1995
    Date of Patent: November 17, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventors: John Keith Nelson, John Arthur Palmer
  • Patent number: 5827352
    Abstract: A method for removing mercury from a gas stream. In the method, sorbent is injected into the gas stream. Water is dispersed into the gas stream to create a cooled gas stream. The cooled gas stream is allowed to dwell with the sorbent in a chamber to remove mercury from the cooled gas stream. The cooled gas stream is passed through an electrostatic precipitator located above the chamber which collects water and recycles the collected water back into the chamber for cooling the gas stream in the chamber. An apparatus for removing mercury from a gas stream is also provided.
    Type: Grant
    Filed: April 16, 1997
    Date of Patent: October 27, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventors: Ralph F. Altman, Ramsay Chang, Robert M. Henningsgaard, Ronald W. Elsner
  • Patent number: 5825113
    Abstract: A permanent magnet machine combines both principles of variable reluctance machines and permanent magnets, and comprises a rotor with salient rotor poles and a stator with salient stator poles. A pair of ferrite arched permanent magnets are embedded in the stator yoke beneath respective stator poles and are arranged symmetrically around the central axis of the machine. A field winding for boosting or weakening the primary flux generated by the permanent magnets is wound in a special arrangement.
    Type: Grant
    Filed: July 5, 1995
    Date of Patent: October 20, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventors: Thomas A. Lipo, Yue Li
  • Patent number: 5825112
    Abstract: A new class of doubly-salient motors which incorporate a specific stator/rotor pole arrangement and stationary permanent magnets mounted in the stator to provide a linearly increasing flux linkage over the entire area of pole overlap. The new motors provide greater output torque, higher efficiency, quicker response, and a simpler structure in comparison to conventional reluctance motors.
    Type: Grant
    Filed: August 6, 1992
    Date of Patent: October 20, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventors: Thomas A. Lipo, Yuefeng Liao, Feng Liang
  • Patent number: 5814824
    Abstract: The present invention relates a composite insulation and shielding article and a method of permanently installing the composite article onto a system to provide at least radioactive shielding. The composite shielding for permanently reducing radioactive radiation emanating from a system comprises at least one inner layer, at least one outer layer, and a shielding layer between said inner and outer layers, said shielding layer comprising a shield material that reduces said radioactive radiation.
    Type: Grant
    Filed: August 22, 1996
    Date of Patent: September 29, 1998
    Assignees: Commonwealth Edison Company, Electric Power Research Institute, Inc., Sargent & Lundy, LLC, Transco Products, Inc.
    Inventors: Peter N. Hamby, Frank P. Polak, David E. Olson, Edward J. Wolbert, Bruce J. Alpha, Bryan L. Risley
  • Patent number: 5798916
    Abstract: A high power inverter pole for a voltage sourced inverter suitable for providing compensation in electric power transmission and distribution systems, has a positive switching valve and a negative switching valve connected between closely spaced dc-source terminal, respectively, and a common ac terminal to form a current loop with minimum loop area thereby reducing stray loop inductance and limiting the overshoot voltage on serially connected electronic switches which make up the valves. In a preferred embodiment, the valves are mounted on opposite sides of the web of an insulative I-beam. The electronic switches are incorporated in modular switching units connected in series by C-channel connecting conductors having flanges bolted to the I-beam flanges. The modular units include broad, flat conductors bolted through end flanges to the C-channel connecting conductors. The electronic switches and anti-parallel diodes of the modular units are clamped between these broad, flat conductors.
    Type: Grant
    Filed: March 20, 1997
    Date of Patent: August 25, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventors: Eric John Stacey, George Studley Bettencourt
  • Patent number: 5784892
    Abstract: A heat pump system capable of heating and cooling an indoor space includes a refrigerant compressor having a discharge side and a suction side interconnected with respective indoor and outdoor heat exchanger coils via a reversing valve, and a condensed refrigerant line interconnecting the indoor and outdoor heat exchangers. Refrigerant charge can be variably added or taken away from the system based on operating conditions using a refrigerant reservoir having a flow regulated first valve connected to the condensed refrigerant line and a similar second valve connected to the suction side. A flow regulated third valve is used to bleed vapor from the reservoir to lower the pressure of refrigerant contained therein relative to the pressure in the liquid line.
    Type: Grant
    Filed: September 9, 1996
    Date of Patent: July 28, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventor: Wayne P. Reedy
  • Patent number: 5785847
    Abstract: The present invention provides a process and apparatus for cleaning and reclamation of an industrial waste containing oily metallic solids by magnetically concentrating the oily magnetic solids, mixing the concentrated solids with a chemical release agent, applying microwave radiation to the mixture, and separately collecting the clean metallic solids and recovered oil components.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: July 28, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventors: David A. Purta, Alberto M. Guzman
  • Patent number: 5778675
    Abstract: The invention provides a stand-alone, hybrid combustion turbine derivative power generation system sized for the most efficient and cost-effective base load operation that is also capable of providing, using air storage techniques, short-duration peak power, which is approximately 200% of the base load rating, and short-duration intermediate load power over a whole a range of loads between a base load and a peak load. The peak/intermediate power is also delivered with the best practical efficiency possible. The hybrid system may employ a variety of combustion turbine thermal cycles, including a simple cycle combustion turbine plant, combustion turbine plants with intercooling, reheat, recuperation, steam injection and humidification, and combined cycle power plants.
    Type: Grant
    Filed: June 20, 1997
    Date of Patent: July 14, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventor: Michael Nakhamkin
  • Patent number: 5748500
    Abstract: An apparatus and method to assess the performance of a start of a turbine is described. The apparatus includes an accumulator to compare a set of on-line data signals corresponding to the starting performance of the turbine to a set of normative starting parameters so as to identify a set of comparison signals. The comparison signals may also be identified by comparing the set of on-line data signals with a database of historical information relating to starts and design profiles of the turbine. In addition, the comparison signals may be identified by comparing the set of on-line data signals with information in an expert system defining fault conditions in previous starts of the turbine. The comparison signals are processed by an analyzer to identify those comparison signals that exceed predetermined thresholds.
    Type: Grant
    Filed: November 14, 1995
    Date of Patent: May 5, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventors: George Heinz Quentin, Robert Alfred Yannone
  • Patent number: 5746971
    Abstract: A method of producing low volatility amines for power plant pH control by in-situ hydrolytic decomposition of a more volatile amine with a ring structure. A ring amine having a certain molecular weight and a volatility is introduced into the pressurized water reactor. The ring amine undergoes at least partial in-situ hydrolytic decomposition to produce at least one daughter amine. The daughter amine has a molecular weight equal to or greater than the ring amine and has a volatility less than the ring amine. The daughter amine, and the mixture of the daughter amine and the ring amine act to control the pH in the reactor. In an alternative embodiment, the ring amine undergoes complete decomposition to form at least one daughter amine, and the daughter amine(s) acts to control the pH in the reactor.
    Type: Grant
    Filed: January 24, 1997
    Date of Patent: May 5, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventors: Peter J. Millett, Alan D. Miller
  • Patent number: 5734588
    Abstract: Guided ultrasonic waves are used for the detection of defective tubes in a heat exchanger or steam generator by using a transducer which generates a guided wave at predetermined parameters of phase velocity and frequency to operate at a point on a dispersion curve which minimizes leakage of ultrasonic energy to fluid surrounding the tube. Various techniques of generating ultrasonic waves of various phase velocities such as a comb type filter allow phase velocity points on a dispersion curve to be freely selected.
    Type: Grant
    Filed: June 24, 1996
    Date of Patent: March 31, 1998
    Assignee: Electric Power Research Institute Inc.
    Inventors: Joseph L. Rose, John J. Ditri, Frank T. Carr, Jack C. Spanner, Jr., Dale Jiao
  • Patent number: 5734257
    Abstract: A transmission line power controller for controlling the flow of electric power in an alternating current three-phase transmission system is described. The power line controller includes a parallel inverter connected to a series inverter through a dc link. The parallel inverter is connected in shunt to the transmission system through a shunt transformer. The series inverter is connected in series with the transmission system through a series transformer. A transmission line power control circuit is used to specify a desired real power demand and reactive power demand for the transmission system. The power control circuit processes this information along with a transmission line voltage vector and a transmission line current vector to produce a voltage source reference signal that is applied to the series inverter. In response to the voltage source reference signal, the series inverter produces an injected voltage vector into the transmission system.
    Type: Grant
    Filed: April 4, 1996
    Date of Patent: March 31, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventors: Colin D. Schauder, Scott L. Williams, Laszlo Gyugyi
  • Patent number: 5726574
    Abstract: A method of pinpointing the location between manholes of a fault in an electrical cable typically buried underground in an urban environment, the fault being caused by an insulation defect which may be broken down by a high voltage includes the steps of applying the voltage to break down the fault insulation defect to induce a transient fault pulse on the cable on both sides of the fault traveling away from the fault. By the use of a ferrite type transformer coupler producing an output voltage, the direction of the transient fault pulse is determined by relating the polarity of the output voltage to the initial high voltage pulse which was applied.
    Type: Grant
    Filed: March 11, 1996
    Date of Patent: March 10, 1998
    Assignee: Electric Power Research Institute, Inc
    Inventors: Michael H. Silverberg, Jack F. Trezza
  • Patent number: 5717143
    Abstract: An apparatus for analyzing bolt loads which includes first and second flanges having opposed faces. A plurality of bolts extend through the faces for securing the flanges together. A sensor is carried by each of the bolts for measuring the load experienced by the bolt. An output mechanism is coupled to the sensor for permitting the load on one of the bolts to be analyzed relative to the load on another of the bolts.
    Type: Grant
    Filed: June 14, 1996
    Date of Patent: February 10, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventors: John M. Jenco, E. Stephen Hunt