Patent US2595368A successfully refreshed from Google Patents.
Patent US4461152A successfully refreshed from Google Patents.
US4461152A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control apparatus for steam turbine
Assignee: Hitachi Ltd
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Filing: 1982-04-12
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Granted: 1984-07-24
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Expires: 2002-04-12
Abstract
Abstract In a steam turbine used with a power plant operated under variable pressure of the steam which is fed to the turbine through control valves, the control apparatus is arranged to control the control valves according to a signal obtained by adding an opening set signal with a compensation signal which is determined in dependence on a difference between a turbine stage steam pressure signal and a signal derived by multiplying the opening set signal with a ratio of the actual value of the control valve inlet steam pressure to a rated value thereof.
Inventors
- 👤 Yasuhiro Tennichi
- 👤 Naganobu Honda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 14:29
CPC Classifications
F; F01; F01D; F01D17/00; F01D17/02; F01D17/08; F01D17/20; F01D17/22; F01D17/24
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
137 words
An apparatus for controlling a steam turbine of a thermal power plant operated under a variable steam pressure, the apparatus comprising means for detecting a turbine stage pressure and for supplying an output signal thereof, means for controlling an opening of control valve means provided at an inlet side of the steam turbine, means for detecting a steam pressure at the inlet side of said control valve means and for providing an output signal thereof, and means for receiving the output signals from said turbine stage pressure detecting means and said steam pressure detecting means and for providing a modified opening set signal to the controlling means whereby the opening of the control valve means is controlled on the basis of said turbine stage pressure and the steam pressure at the inlet of said control valve means.
Claim 2
Independent Claim
137 words
An apparatus for controlling a steam turbine of a thermal power plant operated under a variable steam pressure, the apparatus comprising means for detecting a turbine stage pressure and for supplying an output signal thereof, means for controlling an opening of control valve means provided at an inlet side of the steam turbine, means for detecting a steam pressure at the inlet side of said control valve means and for providing an output signal thereof, and means for receiving the output signals from said turbine stage pressure detecting means and said steam pressure detecting means and for providing a modified opening set signal to the controlling means whereby the opening of the control valve means is controlled on the basis of said turbine stage pressure and the steam pressure at the inlet of said control valve means.
Claim 3
Dependent Claim
39 words
A turbine control apparatus according to claim 1, wherein said means for detecting the turbine stage pressure is disposed so as to detect the pressure of steam discharged from a first stage high pressure turbine of said steam turbine.
Claim 4
Dependent Claim
25 words
A turbine control apparatus according to claim 1, further comprising means for reheating steam discharged from a high pressure turbine stage of said steam turbine.
Claim 5
Independent Claim
175 words
An apparatus for controlling a steam turbine of a thermal power plant operated under a variable steam pressure, the apparatus comprising means for detecting an opening of control valve means provided at an inlet side of the steam turbine and providing an output signal thereof, means for detecting a turbine stage pressure and providing an output signal thereof, means for determining a compensation signal in dependence upon a difference between the output signals of the opening detecting means and the turbine stage pressure means, means for providing a modified opening set signal for controlling an opening of the control valve means in dependence upon the compensation signal; means for detecting a pressure prevailing at an inlet of the control valve means and for providing an output signal of a detected pressure; and means for receiving the output signals of the pressure prevailing at the inlet of the control valve means and for correctively modifying a magnitude of said compensation signal by the pressure of the steam prevailing at the inlet of said control valve means.
Claim 6
Independent Claim
175 words
An apparatus for controlling a steam turbine of a thermal power plant operated under a variable steam pressure, the apparatus comprising means for detecting an opening of control valve means provided at an inlet side of the steam turbine and providing an output signal thereof, means for detecting a turbine stage pressure and providing an output signal thereof, means for determining a compensation signal in dependence upon a difference between the output signals of the opening detecting means and the turbine stage pressure means, means for providing a modified opening set signal for controlling an opening of the control valve means in dependence upon the compensation signal; means for detecting a pressure prevailing at an inlet of the control valve means and for providing an output signal of a detected pressure; and means for receiving the output signals of the pressure prevailing at the inlet of the control valve means and for correctively modifying a magnitude of said compensation signal by the pressure of the steam prevailing at the inlet of said control valve means.
Claim 7
Dependent Claim
55 words
A turbine control apparatus according to claim 4, wherein said means for receiving and correctively modifying is adapted to multiply either said opening output signal or said turbine stage pressure output signal with a ratio between a rated value and an actual valve of the steam pressure at the inlet of the control valve means.
Claim 8
Dependent Claim
44 words
A turbine control apparatus according to claim 5, wherein the ratio with which said opening output signal is multiplied is a ratio of the actual value of the control valve inlet steam pressure to the rated value of the control valve inlet steam pressure.
Claim 9
Dependent Claim
43 words
A turbine control apparatus according to claim 5, wherein the ratio with which said opening signal is multiplied is a ratio of the rated value of the control valve inlet steam pressure to the actual value of said control valve inlet steam pressure.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-07-24 | 1988-01-23 | 1988-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-24 | 1992-01-23 | 1992-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-24 | 1996-01-23 | 1996-07-24 | $7700.00 | Window Closed / Lapsed |