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. 16, 1980
Filed:
Jul. 12, 1978
Applicant:
Inventors:
Ryuji Iyotani, Hitachi, JP;
Atsumi Watanabe, Hitachi, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03K / ;
U.S. Cl.
CPC ...
3072 / ; 3072 / ; 363 68 ;
Abstract
A thyristor valve includes a plurality of thyristors connected in series and series circuits each including a capacitor and a resistor and connected in parallel with each thyristor. A pulse from a pulse generator for firing the thyristors is applied to them at the beginning of a prescribed period of conduction of the thyristor valve when voltage across the selected one of the thyristors is forward. An output signal of a current detector provides a firing pulse to all thyristors when the valve current exceeds a predetermined current value during the prescribed period of conduction of the thyristor valve.