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. 27, 1987
Filed:
Apr. 23, 1986
Lennart Stenstrom, Ludvika, SE;
Asea Aktiebolag, , SE;
Abstract
As overvoltage protection for a series capacitor (C1-C5) in a high-voltage network a voltage-dependent resistor (Z6), built up of metal oxide varistors, is arranged in parallel with the capacitor. In parallel with the resistor there is a spark gap means consisting of two series-connected spark gaps (G1, G2) for shunting the resistor in case of overload thereof. The energy for triggering the spark gap means is obtained from an auxiliary capacitor (C5), which is charged during operation, and is supplied to one of the spark gaps (G2) via a switching means (T1, T2), controlled by an overload detector (CU), and a pulse transformer (TR). A metal oxide varistor (Z5) is connected in series with the high voltage winding of the transformer. The transformer is connected so that the triggering pulse is in opposition to the voltage across the series capacitor.