Patents Assigned to New England Power Service Company
  • Patent number: 4559520
    Abstract: A method for improving signal quality while simultaneously enhancing the data rate in a communications system in which individual signaling events are, at least in principle, capable of representing a bit of digital intelligence. When the method is applied to power-line communication systems, the pattern of signaling events extends over some integer multiple of four cycles of the power-line wave. Signaling events of each particular type are found in exactly half of the cycles contained in any pattern. Patterns containing but one type of signaling event are arranged into orthogonal patterns--the term orthogonal implying that each pattern can be sensed only by a detection mode that maximizes the signal therefrom, and the application of any detection mode to a pattern for which it is not optimum will result in no net accumulation of signal.
    Type: Grant
    Filed: June 23, 1982
    Date of Patent: December 17, 1985
    Assignee: New England Power Service Company
    Inventor: Reed H. Johnston
  • Patent number: 4473535
    Abstract: A process for reducing nitric oxide with ammonia in the presence of a copper-exchanged mordenite catalyst at a temperature between about 300.degree. F. and 800.degree. F.
    Type: Grant
    Filed: October 16, 1981
    Date of Patent: September 25, 1984
    Assignees: Northeast Utilities Service Company, New England Power Service Company
    Inventors: James R. Kittrell, Donald L. Herman
  • Patent number: 4400688
    Abstract: A method and an apparatus for communicating over electric power lines in a direction from load to source is disclosed. The power line voltage wave is loaded in a predetermined pattern to produce a corresponding pattern of signaling currents at a receiving site. Detection of the signaling current is accomplished in the preferred embodiment by integrating the current in the phase or the neutral of the feeder that serves the signaling site during predetermined time windows which are synchronized with the power line voltage wave. The current integration is performed in accordance with a detection algorithm to accumulate principally the current differences that are attributable to the signaling currents while in the presence of steady and transient currents on the feeder.
    Type: Grant
    Filed: October 15, 1980
    Date of Patent: August 23, 1983
    Assignee: New England Power Service Company
    Inventors: Reed H. Johnston, Dennis C. Jeffreys, Lawrence J. Stratton, Albert W. Welz, Jr.
  • Patent number: 4246234
    Abstract: A method and apparatus for reducing nitric oxide in a gas with ammonia in the presence of a base metal catalyst pretreated with sulfur, selenium or a sulfur compound positioned in a reactor. The catalyst is deposited on a substrate or confined between gas-permeable walls and arranged to form open channels through which the nitric oxide-containing gas thereby effects low pressure drop through the reactor.
    Type: Grant
    Filed: May 26, 1978
    Date of Patent: January 20, 1981
    Assignees: New England Power Service Company, Northeast Utilities Service Company
    Inventors: James R. Kittrell, Donald L. Herman
  • Patent number: 4218655
    Abstract: A method and apparatus for transmitting intelligence over a carrier wave are disclosed in which a signal waveform is added to a carrier wave to produce a composite wave having a recognizable pattern of variations in intervals that are defined by preselected locations in the composite wave. The pattern of variations in intervals resulting from the addition of the signal waveform to the carrier wave represents at least a portion of the intelligence to be transmitted over the carrier wave. The variations in intervals defined by the preselected locations in the carrier waves are detected and the detected interval variations are converted into a signal which has a characteristic that is a function of the recognizable pattern of interval variations. In the preferred embodiment the intelligence is transmitted over an electric power distribution network utilizing the alternating voltage therein as the carrier wave.
    Type: Grant
    Filed: December 14, 1977
    Date of Patent: August 19, 1980
    Assignee: New England Power Service Company
    Inventors: Reed H. Johnston, Dennis C. Jeffreys, Lawrence J. Stratton
  • Patent number: 4201552
    Abstract: Coal-oil slurries are provided which contain a cationic stabilizer containing the group, >N--CH.sub.2 --CH.sub.2 --O--. The stabilizer can comprise a quaternary ammonium salt or a tertiary amine.
    Type: Grant
    Filed: July 20, 1978
    Date of Patent: May 6, 1980
    Assignee: New England Power Service Company
    Inventors: Robert L. Rowell, Stephen R. Vasconcellos
  • Patent number: 4105897
    Abstract: A cycloconverter apparatus and method is disclosed in which the cycloconverter works into an active load. The cycloconverter is connected between an external power source and a load so that the load current flows through the cycloconverter. In the preferred embodiment, the cycloconverter is used to impress a signaling voltage waveform upon the voltages of the three phases of an electric power distribution feeder. This voltage is impressed by injecting it between the common point of the wye-connected secondary of the substation transformer and the grounded neutral that serves all phases of the distribution feeder. The neutral current of the distribution feeder flows through the cycloconverter. Protective by-pass circuitry is provided to maintain the integrity of the neutral path in the event of a phase-to-neutral short circuit or a failure of the cycloconverter.
    Type: Grant
    Filed: April 13, 1976
    Date of Patent: August 8, 1978
    Assignee: New England Power Service Company
    Inventors: Lawrence J. Stratton, Dennis C. Jeffreys, Albert W. Welz, Jr., Reed H. Johnston
  • Patent number: 4106007
    Abstract: A method and apparatus for transmitting intelligence over a carrier wave are disclosed in which a signal wave is combined with a carrier wave to produce a composite wave having a recognizable pattern of variations in intervals that are defined by preselected locations in the composite wave. The pattern of variations in intervals resulting from the combination of the signal wave with the carrier wave represents at least a portion of the intelligence to be transmitted over the carrier wave. The intelligence is extracted from the composite wave for subsequent utilization. In the preferred embodiment the intelligence is transmitted over an electric power distribution network utilizing the alternating wave thereon as the carrier wave. The variations in intervals defined by the preselected locations in the composite wave are detected and the detected interval variations are converted into a signal which has a characteristic that is a function of the recognizable pattern of interval variations.
    Type: Grant
    Filed: July 1, 1975
    Date of Patent: August 8, 1978
    Assignee: New England Power Service Company
    Inventors: Reed H. Johnston, Dennis C. Jeffreys, Lawrence J. Stratton
  • Patent number: 4089930
    Abstract: Base metal catalysts are pretreated with selenium, sulfur or sulfur compounds. Subsequently, a gaseous stream comprising nitric oxide, oxygen and ammonia is passed over the pretreated catalysts. The nitric oxide is reduced to nitrogen and no nitrous oxide is formed.
    Type: Grant
    Filed: February 12, 1976
    Date of Patent: May 16, 1978
    Assignees: New England Power Service Company, Northern Utilities Service Company
    Inventors: James R. Kittrell, Donald L. Herman
  • Patent number: 4080426
    Abstract: Base metal catalysts are pretreated with selenium, sulfur or sulfur compounds. Subsequently, a gaseous stream comprising nitric oxide, oxygen and ammonia is passed over the pretreated catalysts. The nitric oxide is reduced to nitrogen and no nitrous oxide is formed.
    Type: Grant
    Filed: April 11, 1977
    Date of Patent: March 21, 1978
    Assignees: New England Power Service Company, Northeast Utilities Service Company
    Inventors: James R. Kittrell, Donald L. Herman