Electricity: electrical systems and devices – Safety and protection of systems and devices – With specific voltage responsive fault sensor
Patent
1987-04-24
1988-11-29
A., D.
Electricity: electrical systems and devices
Safety and protection of systems and devices
With specific voltage responsive fault sensor
361 62, 361 59, 361 75, 361 89, 364483, 340663, H02H 320
Patent
active
047886196
ABSTRACT:
Protective relay for use in an electrical power system having electrical conductors which are energizable with an AC voltage. The protective relay includes a circuit for sensing the AC voltage to produce an AC output that has zero crossings and a time period between zero crossings, a circuit for supplying an electrical signal representing a preselected pickup value of volts-per-Hertz for the relay, and a circuit responsive to the AC output and to the electrical signal for generating an electrical level as a function of both the time period and the pickup value and for producing an output signal for the relay when the AC output exceeds the electrical level. In this way, the output signal is produced when a volts-per-Hertz value of the AC voltage exceeds the preselected pickup value of volts-per-Hertz for the relay. Other protective relay apparatus and methods are also disclosed.
REFERENCES:
patent: 3590326 (1971-06-01), Watson
patent: 3703717 (1972-11-01), Kuster
patent: 4246623 (1981-01-01), Sun
patent: 4272816 (1981-06-01), Matsumoto
patent: 4420805 (1983-12-01), Yamaura et al.
patent: 4428022 (1984-01-01), Engel et al.
patent: 4535409 (1985-08-01), Jindrick et al.
patent: 4694374 (1987-09-01), Verbanets, Jr.
patent: 4701690 (1987-10-01), Fernandez et al.
Elmore et al., "Overexcitation Analysis and Detection with Microprocessor-Based Relay", in Minnesota Power Systems Conference, 12 pp., Oct. 7-9, 1986.
ASEA, "Over-Excitation Relay Type RATUA", Edition 1, 2/76, File R, Part 1, 4 pages.
MCS-48 .TM. Family of Single Chip Microcomputers User's Manual, Intel, Sep. 1980, Face Sheet plus pp. 1-1 thru 1-15 and 4-1 thru 4-8.
ASEA, "Type RATUB V/Hz Overexcitation Relay for Transformers", pp. 1-3, 6/30/82.
Beckwith Electric Co., "Pride Programmable Overexcitation Relay", 8 pages Specifications, 2 pages Table of Contents and pp. 1.59 of text. (pp. 54, 56, 58 absent.) 6-1982.
Meisinger et al., "An Overexcitation Relay with Inverse Time Characteristics", Pennsylvania Elec. Assoc., Relay Com. Mtg., Pittsburgh, PA, pp. 1-6, 5.25.84.
Pettigrew, "Overexcitation Protection with Microprocessor Based Volts Per Hertz Relay", Pennsylvania Elec. Assoc., Relay Com. Mtg., Allentown, PA, pp. 1-19, 1.18.85.
Basler Electric Co., "EDM 200 Exciter Diode Monitor", 4 pages, 1.85.
Westinghouse Electric Corp., "Type MVH Microprocessor Volts Per Hertz Relay", 17 pages, 5-1985.
Lakin et al., "Advanced Overexcitation Protection for Generators and Transformers", Pennsylvania Elec. Assoc., Generator Subcom. of Relay Com., pp. 1-9, 9.20.85.
Pettigrew et al., "Operating and Application Experience with a Microprocessor-Based Volts Per Hertz Relay, 40th Annual Conf. for Protective Relay Engrs., Title Page, Abstract, Table of Contents, pp. 1-27, Apr. 13-15, 1987.
Ott Matthew J.
Wilkerson Timothy M.
A. D.
Basler Electric Company
Jennings Derck S.
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