초록 ▼

It is proposed that, during the operation of a steam turbine of a steam power plant, the internal pressure and also the internal temperature and, in the region outside it, the external temperature be determined in at least one steam-carrying component. As a result of a change in the operating state,

It is proposed that, during the operation of a steam turbine of a steam power plant, the internal pressure and also the internal temperature and, in the region outside it, the external temperature be determined in at least one steam-carrying component. As a result of a change in the operating state, in particular in the event of a load change, then, the abovementioned values vary, so that, under some circumstances, the mechanical stresses which in this case act on the steam-carrying component become unacceptably high. Consequently, a spatial temperature distribution and a reference stress of the steam-carrying component are determined from the abovementioned values and compared with a material limit stress. If the reference stress is greater than the material limit stress, a limit steam pressure desired value is determined, and at least one steam valve is set in such a way that the steam pressure on the steam-carrying component corresponds approximately to this limit steam pressure desired value. By the method according to the invention, an automatic reduction in the throttling is obtained, so that the efficiency of the steam power plant, in particular in the part-load range, is increased. A device according to the invention serves for carrying out the method according to the invention.

대표청구항 ▼

1. A method for operating a steam power plant having a steam turbine, a steam-carrying component and a steam valve to deliver steam to the steam turbine, comprising:during the operation of the steam power plant, determining an internal pressure, an internal temperature and an external temperature of

1. A method for operating a steam power plant having a steam turbine, a steam-carrying component and a steam valve to deliver steam to the steam turbine, comprising:during the operation of the steam power plant, determining an internal pressure, an internal temperature and an external temperature of the steam-carrying component; determining a spatial distribution of the internal temperature and the external temperature; from the internal pressure, the internal temperature and the external temperature, determining a reference stress, which describes a current mechanical stress being applied to the steam-carrying component; comparing the reference stress with a material limit stress which describes an upper limit for the mechanical load-bearing capacity of the steam-carrying component; and if the reference stress is greater than the material limit stress: determining a limit steam pressure, which describes a maximum permissible steam pressure, by which the steam-carrying component can be acted upon without the risk of damage in the current operating state, and setting the steam valve so that the steam carried by the steam-carrying component is at a pressure which corresponds approximately to the limit steam pressure. 2. The method as claimed in claim 1, wherein the steam-carrying component is a steam separation drum.3. The method as claimed in claim 1, wherein the steam turbine has at least two turbine stages.4. The method as claimed in claim 1, wherein the steam turbine has a high pressure stage and a low pressure stage.5. The method as claimed in claim 4, whereina stage valve controls delivery of steam to the low-pressure turbine stage, and the stage valve is set in conjunction with the steam valve. 6. The method as claimed in claim 1, wherein the limit steam pressure is determined by a simulation calculation.7. The method as claimed in claim 2, wherein the steam turbine has a high pressure stage and a low pressure stage.8. The method as claimed in claim 7, whereina stage valve controls delivery of steam to the low-pressure turbine stage, and the stage valve is set in conjunction with the steam valve. 9. The method as claimed in claim 8, wherein the limit steam pressure is determined by a simulation calculation.10. The method as claimed in claim 1, wherein the steam-carrying component carries steam from the turbine.11. A device for operating a steam power plant having a steam turbine, a steam-carrying component, and a steam valve to deliver steam to the steam turbine, comprising:an internal-pressure sensor to sense a pressure within the steam-carrying component; an internal temperature unit to determine an internal temperature of the steam-carrying component; an external-temperature sensor to sense an outer temperature of the steam-carrying component; a computing stage to receive the internal pressure, the internal temperature and the external temperature, to determine a spatial distribution of the temperature of the steam-carrying component, and to determine a reference stress describing a current mechanical stress being applied to the steam-carrying component; a comparison stage to compare the reference stress with a material limit stress which describes an upper limit for the mechanical load-bearing capacity of the steam-carrying component; and a regulating stage, triggered if the reference stress is greater than the material limit stress: to determine a limit steam pressure, which describes a maximum permissible steam pressure by which the steam-carrying component can be acted upon without the risk of damage in the current operating state, and to regulate the steam valve so that the steam carried by the steam-carrying component is a pressure which corresponds approximately to the limit steam pressure. 12. The device as claimed in claim 11, wherein the steam-carrying component is a steam separation drum.13. The device as claimed in claim 11, wherein the steam turbine has at least two turbine stages.14. The device as claimed in claim 11, wherein the steam turbine has a high pressure stage and a low pressure stage.15. The device as claimed in claim 14, whereina stage valve controls delivery of steam to the low-pressure turbine stage, and the stage valve is set in conjunction with the steam valve. 16. The device as claimed in claim 11, wherein the limit steam pressure is determined by a simulation calculation.17. The device as claimed in claim 12, wherein the steam turbine has a high pressure stage and a low pressure stage.18. The device as claimed in claim 17, whereina stage valve controls delivery of steam to the low-pressure turbine stage, and the stage valve is set in conjunction with the steam valve. 19. The device as claimed in claim 18, wherein the limit steam pressure is determined by a simulation calculation.20. The device as claimed in claim 11, wherein the steam-carrying component carries steam from the turbine.