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:
Mar. 07, 1995
Filed:
Feb. 04, 1993
Edmond Thuries, Meyzieu, FR;
Martin Motz, Villeurbanne, FR;
GEC Alsthom SA, Paris, FR;
Abstract
A pumping station feeds hydraulic energy to a grid or raises water from a low level to a high level. It includes, in particular, a transformer connected between an alternator and a grid, with a circuit breaker between the transformer and the grid. It further includes resistance for limiting the surge current through the transformer. This resistance lies in the range of 500 ohms to 100,000 ohms and is inserted for a period lying in the range 15 milliseconds to 19 milliseconds when the circuit breaker is closed, and a controller for ensuring that the circuit breaker closes on the unloaded transformer only at an instant that is no more than 1.2 milliseconds from an extreme value in the grid voltage.