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. 21, 1987
Filed:
Dec. 28, 1984
Toshihiko Higashi, Hitachi, JP;
Yasuhiro Tennichi, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A steam turbine governor system including two governor electronic sections for producing a turbine valve opening command to control the opening of steam valves thereby controlling a flow of steam into the turbine in dependence upon a difference between an actual turbine speed and a target turbine speed and a target turbine load. One governor electronic sections is actually used for controlling the opening of the steam valves, while the other governor electronic section is a stand-by. A first value relating to the turbine speed acceleration rate based on the turbine valve opening command produced by each of the governor electronic sections is obtained so that the first values are obtained parallelly and independently of each other in the two governor electronic sections. Turbine valve opening commands produced by the respective governor electronic sections are compared with each other and produce a start signal when the difference between them exceeds a predetermined level. A second value relating to the turbine speed acceleration rate based on the actual turbine speed is obtained, and a majority logic is applied to the first values obtained by the two governor electronic sections and the second value. An abnormality of any of the governor electronic sections is obtained based on the result of application of the majority logic.