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:
Apr. 15, 1997
Filed:
Oct. 03, 1995
Asea Brown Boveri AB, Vasteras, SE;
Abstract
An installation for transmission of high-voltage direct current comprises a first and a second converter (SR1, SR2, respectively), each one controlled by a separate piece of control equipment (CE1, CE2, respectively). Each one of the pieces of control equipment comprises a current controller (CC). The current controller of the second converter is supplied with a second current reference value (IOL2) and a current margin (IOM). The control equipment of the second converter comprises a function-forming member (11), which in dependence on an applied measured value (UD) of the direct voltage forms the current margin such that, when the direct voltage exceeds a first preselected voltage level (Udf), it assumes a first value (IOMf) and, when the direct voltage is lower than the first voltage level, it assumes a second value (IOMs), the magnitude of the second value being greater than the magnitude of the first value.