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:
Oct. 14, 1980
Filed:
Jul. 28, 1978
Hiroshi Matsumoto, Hitachi, JP;
Yoshio Sato, Hitachi, JP;
Shigeyoshi Kawano, Hitachiota, JP;
Yoshiyuki Nakano, Hitachi, JP;
Fumio Kato, Hitachi, JP;
Katsukuni Hisano, Hitachi, JP;
Katsuto Kashiwahara, Hitachi, JP;
Yasuhiko Otawara, Katsuta, JP;
Toshihiko Higashi, Hitachi, JP;
Yasuhiro Tennichi, Hitachi, JP;
Jube Matsumura, Hitachi, JP;
Koichiro Fukushima, Hitachi, JP;
Hitachi, Ltd., , JP;
Abstract
The present stress in the turbine rotor is estimated at each control period, from the steam temperature and pressure at the turbine inlet. In addition, the future turbine inlet steam temperature or pressure is preestimated once every n.sub.T control cycles, for a given speed or load changing rate, making use of data concerning the changing rate of the turbine steam inlet temperature or pressure in relation with the change of the speed or load, which has been obtained by a learning of the past turbine operating condition. This future steam temperature or pressure at the turbine inlet is used as a factor for preestimating the future stress expected to be caused in the turbine rotor. The preestimation of the rotor stress is performed for a plurality of assumed speed or load changing rates. The turbine is controlled at the maximum speed increase-rate or load changing rate which would not cause the future stress preestimated over a given preestimation time to exceed a limit stress. An observation of the present stress is made at each control period to check whether the limit stress is not exceeded by the present stress.