The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 20, 1981
Filed:
Jun. 01, 1979
Leif Eriksson, Sala, SE;
Salomon Liberman, Ra'anana, IL;
Asea Aktiebolag, Vesteras, SE;
Abstract
In circuitry for generating tripping and blocking signals for the protection of electrical components in an electrical power supply network as a result of the occurrence of faults therein, respective tripping and blocking outputs for each phase of an electrical power supply network are generated such that double or triple pole tripping is prevented unless the presence of an actual second tripping signal is detected subsequent to the detection of a first tripping signal. The respective tripping signals and blocking signals for each phase of the electrical power supply network are generated in dependence on whether the fault lies ahead or behind the electrical component to be protected, respectively, in response to measurement of the voltage and current associated with transient waves generated by faults in each electrical power supply network phase. The presence of a tripping signal resulting from the occurrence of a single phase fault, and the presence of a second tripping signal resulting from the occurrence of a fault in another phase are detected. The functional level of detecting the second tripping signal is modified or adjusted upon detection of the first tripping signal.