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:
Jun. 09, 1987
Filed:
Jul. 29, 1985
Ray Stanyard, Buchrain, CH;
Hansruedi Liechti, Buchrain, CH;
Inventio AG, Hergiswil, CH;
Abstract
A twelve-pulse converter has an a.c.-input and a d.c.-output which is connected with an armature via two thyristors of a change-over circuit. An extinguishing circuit comprises a resistor, a capacitor, an inductor and a thyristor which is also connected with the armature via related diodes. A current transformer in the armature circuit causes ignition of the thyristor in the extinguishing circuit at the occurrence of excess current. The extinguishing capacitor is continuously connected with a charging circuit and is connected parallel to the thyristor of the extinguishing circuit and with the thyristors connected to the d.c.-negative pole. The d.c.-negative pole connected thyristors are cut-off when the thyristor of the extinguishing circuit is ignited and the energy appearing in the armature circuit is dissipated by the resistor in the extinguishing circuit. The zero-crossing of the current is detected by means of two voltage converters which are connected with the d.c.-negative pole and the d.c.-positive pole of the converter as well as with the armature. The non-current conducting thyristors which are connected either with the d.c.-negative pole or with the d.c.-positive pole, are ignited by means of information derived from the voltage converters.