US3928977A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrohydraulic on-line testable trip system for turbine power plant
Assignee: Westinghouse Electric Corp
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Filing: 1974-06-06
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Granted: 1975-12-30
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Expires: 1994-06-06
Abstract
Abstract An electrohydraulic trip system for closing rapidly the steam inlet valves to a turbine power plant is disclosed. The system includes redundant components for sensing and hydraulically responding to a turbine trip contingency. The hydraulic portion includes two pairs of electrically operable trip valves so arranged that at least one valve of each pair must be operated to trip the turbine. A test switch on the test and indication panel initiates the test by simulating the trip contingency environment for a portion of the redundant sensors and operates the system to open only one pair of the trip valves. During such testing operation, the remaining sensors for the same and other trip contingencies are responsive to open the other pair of trip valves to trip the turbine. The testing of the system can be accomplished for each trip contingency for each portion of the system consecutively. The trip contingencies involving pressure, such as bearing oil and vacuum, for example, are simulated and rendered responsive simultaneously to a real trip contingency by a fluid system that includes means for deviating from operating pressure for testing without actually affecting the operational characteristics of the system being tested, or the capability of the system to respond to an actual deviation in pressure. The electrical portion of the system is switched for testing from a dual system to a split system. With respect to the electrical overspeed contingency, the simulation is transferred from one portion of the system to the other for testing.
Inventors
- 👤 Andrew S Braytenbah
- 👤 Karl O Jaegtnes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:14
CPC Classifications
F; F01; F01D; F01D21/00; F01D21/20
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
385 words
An electrohydraulic emergency trip system for a turbine power plant to close rapidly the steam inlet valves to the turbine in response to a predetermined contingency, comprising: a turbine, a plurality of steam inlet valves for controlling the admission of steam to the turbine, a source of trip fluid under pressure, an operating mechanism for each steam inlet valve operative to permit its associated valve to be controllably open in response to a predetermined trip fluid pressure and operative to close in response to a predetermined decrease of trip fluid pressure in communication with such operating mechanism, a fluid draining means, an hydraulic means connecting each operating mechanism in communication with the trip fluid under pressure and the fluid draining means to provide the predetermined trip fluid pressure when the draining means is closed and to decrease the trip fluid pressure when the draining means is open, a first and second electrically operable trip valve means connected in series in the hydraulic means to close the draining means when one of the first and second trip valve means is closed and to open the draining means when both the first and second trip valve means are open, a first and second contingency detecting means both operable to a trip condition in response to a predetermined operating contingency, a first trip circuit means responsive to the operation of the first contingency detecting means to its trip condition to open the first trip valve means, a second trip circuit means responsive to the operation of the second contingency detecting means to its trip condition to open the second trip valve means, contingency simulation means operative when activated to simulate a trip contingency condition, switching circuit means to activate the contingency simulation means to render selectively the first and second contingency detection means responsive to the simulated trip contingency condition, means including the contingency simulation means and the switching circuit means to render one of the first and second cintingency detecting means operative to its trip condition in response to a predetermined contingency at times when the other of the first and second contingency detection means is activated by the contingency simulation means, and indicating means operatively associated with each of the trip valve means to indicate the operation of the respective first and second trip circuit means.
Claim 2
Dependent Claim
385 words
An electrohydraulic emergency trip system for a turbine power plant to close rapidly the steam inlet valves to the turbine in response to a predetermined contingency, comprising: a turbine, a plurality of steam inlet valves for controlling the admission of steam to the turbine, a source of trip fluid under pressure, an operating mechanism for each steam inlet valve operative to permit its associated valve to be controllably open in response to a predetermined trip fluid pressure and operative to close in response to a predetermined decrease of trip fluid pressure in communication with such operating mechanism, a fluid draining means, an hydraulic means connecting each operating mechanism in communication with the trip fluid under pressure and the fluid draining means to provide the predetermined trip fluid pressure when the draining means is closed and to decrease the trip fluid pressure when the draining means is open, a first and second electrically operable trip valve means connected in series in the hydraulic means to close the draining means when one of the first and second trip valve means is closed and to open the draining means when both the first and second trip valve means are open, a first and second contingency detecting means both operable to a trip condition in response to a predetermined operating contingency, a first trip circuit means responsive to the operation of the first contingency detecting means to its trip condition to open the first trip valve means, a second trip circuit means responsive to the operation of the second contingency detecting means to its trip condition to open the second trip valve means, contingency simulation means operative when activated to simulate a trip contingency condition, switching circuit means to activate the contingency simulation means to render selectively the first and second contingency detection means responsive to the simulated trip contingency condition, means including the contingency simulation means and the switching circuit means to render one of the first and second cintingency detecting means operative to its trip condition in response to a predetermined contingency at times when the other of the first and second contingency detection means is activated by the contingency simulation means, and indicating means operatively associated with each of the trip valve means to indicate the operation of the respective first and second trip circuit means.
Claim 3
Dependent Claim
56 words
A system according to claim 1 wherein the first and second trip valve means each include two individual electrically operable trip valves connected in parallel with each other in the hydraulic means to open the drain when only one of the individual trip valves of each of the first and second trip valve means is open.
Claim 4
Dependent Claim
81 words
A system according to claim 1 wherein the first and second contingency detection means each include at least one contingency sensing device normally in one condition and operative to a trip condition in response to a predetermined contingency, and both first and second contingency detection means is operative to its trip condition in response to the operation of one contingency sensing device to the trip condition at times when the contingency simulation means is not activated by the switching circuit means.
Claim 5
Dependent Claim
84 words
A system according to claim 1 wherein the first and second contingency detection means each include at least two contingency sensing devices normally in one condition and operative to a trip condition in response to a predetermined contingency, both first and second contingency detection means is operative to the trip condition in response to the operation of at least two of the contingency sensing devices, and the contingency simulation means is effective to render selectively the contingency sensing devices operative to the trip condition.
Claim 6
Dependent Claim
140 words
A system according to claim 1 wherein the predetermined contingency is a predetermined deviation from a fluid pressure in the power plant, the contingency simulation means comprises: a pipe connected at one end in communication with the fluid pressure to be monitored and open at the other end, a valve means operable electrically to an open and closed condition connected in the pipeline to open and close selectively the open end, fluid flow restriction means in the pipeline between the one end and the valve means configured to restrict the flow of fluid to prevent the predetermined deviation upon the opening of the first valve means, and the contingency detection means includes a pressure responsive switch connected in the pipeline between the restriction means and the valve means to respond to the deviation upon the opening of the valve means.
Claim 7
Dependent Claim
161 words
A system according to claim 5 wherein the predetermined contingency is a predetermined deviAtion from a fluid pressure in the turbine power plant, the contingency simulation means comprises a plurality of pipes each connected at one end in communication with the plant fluid pressure and open at the other end, a valve means operable electrically to an open and closed condition connected in each pipe between the open and other end, a fluid flow restrictive means in each pipe between the one end and each respective valve means configured to restrict fluid flow in each respective pipe to prevent the predetermined deviation upon the opening of the respective valve means, and the first and second contingency detection means each includes at least one pressure responsive switch connected in each of the first and second plurality of pipes between its respective restriction means and valve means to respond to a deviation in its respective pipe upon the opening of the valve means.
Claim 8
Dependent Claim
13 words
A system according to claim 6 wherein the fluid pressure is condenser vacuum.
Claim 9
Dependent Claim
15 words
A system according to claim 6 wherein the fluid pressure is bearing lubricating oil pressure.
Claim 10
Dependent Claim
18 words
A system according to claim 6 wherein the fluid pressure is fluid pressure in the hydraulic trip means.
Claim 11
Dependent Claim
13 words
A system according to claim 1 wherein the predetermined contingency is turbine overspeed.
Claim 12
Dependent Claim
260 words
An electrohydraulic emergency trip system for closing rapidly the movtive fluid inlet valves to a turbine power plant in response to a predetermined contingency comprising a first and second electrically operative contingency detection means, a test switching means operable to a test position and a normal position, first circuit means responsive to a predetermined contingency to operate one of the first and second contingency detection means at times when the test switching means is in a test position and to operate both said first and second detection means at times when the test switching means is in a normal position, a first and second hydraulic valve means, each including at least one valve electrically operable to an open and closed position, hydraulic means operative to maintain the steam inlet valves open at times when one of the first and second valve means is in a closed and operative to close the inlet valves to the turbine in response to the operation of at least one valve of both the first and second valve means to an open position, second circuit means responsive to the operation of one of the first and second contingency detection means to open one of the first and second hydraulic valve means and responsive to the operation of both the first and second contingency detection means to open both the first and second valve means, contingency simulation means operative to simulate selectively for one of the first and second contingency detection means a predetermined operating contingency when the switching means is operated to a test position.
Claim 13
Dependent Claim
260 words
An electrohydraulic emergency trip system for closing rapidly the movtive fluid inlet valves to a turbine power plant in response to a predetermined contingency comprising a first and second electrically operative contingency detection means, a test switching means operable to a test position and a normal position, first circuit means responsive to a predetermined contingency to operate one of the first and second contingency detection means at times when the test switching means is in a test position and to operate both said first and second detection means at times when the test switching means is in a normal position, a first and second hydraulic valve means, each including at least one valve electrically operable to an open and closed position, hydraulic means operative to maintain the steam inlet valves open at times when one of the first and second valve means is in a closed and operative to close the inlet valves to the turbine in response to the operation of at least one valve of both the first and second valve means to an open position, second circuit means responsive to the operation of one of the first and second contingency detection means to open one of the first and second hydraulic valve means and responsive to the operation of both the first and second contingency detection means to open both the first and second valve means, contingency simulation means operative to simulate selectively for one of the first and second contingency detection means a predetermined operating contingency when the switching means is operated to a test position.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-29 | 1979-06-30 | 1979-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-29 | 1983-06-30 | 1983-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-29 | 1987-06-30 | 1987-12-30 | $7700.00 | Window Closed / Lapsed |