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:
Sep. 28, 1982
Filed:
Feb. 25, 1981
Allan T Johns, Corsham, GB;
The General Electric Company Limited, London, GB;
Abstract
This invention relates to methods and apparatus for detecting the occurrence of a fault on a conductor or transmission line and for protecting the conductor or line in accordance with the determination of fault. The instantaneous value of the voltage (V) and current (i), or the modal components of that voltage and current in the case of a polyphase line, are formed into two functions S.sub.1R and S.sub.2R, which are of the general form V-iR and V+iR respectively where R is a replica of the surge impedance of the line. Superimposed components of these functions are derived by continuously subtracting the steady-state value of each function from its instantaneous value. The sequence in which the functions obtain a value outside a predetermined band of values is monitored to provide an indication of the existence and direction of a fault with respect to the measuring point. Trip and block signals are generated for operating circuit breakers.