Thermal power plant generator set adopting superheat to control drain valve on main steam pipeline

Abstract

The invention discloses a thermal power plant generator set adopting superheat to control a drain valve on a main steam pipeline. The thermal power plant generator set comprises a water storage tank, and water in the water storage tank flows back to the water storage tank after being separated through a steam separator. Steam sequentially passes a ceiling superheater, a low-temperature superheater, a screen-type superheater and a high-temperature superheater and then is led to a turbine high-pressure cylinder through the main steam pipeline. The main steam pipeline is provided with a main steam regulation valve and a main steam valve, and is further provided with the drain valve and a turbine main steam valve inlet temperature measurement point. The steam separator is provided with a steam separator outlet temperature measurement point. Temperature signals collected by the turbine main steam valve inlet temperature measurement point and temperature signals collected by the steam separator outlet temperature measurement point are input to a DCS system to be processed, and the DCS system outputs control signals to the drain valve after processing the temperature signals. The thermal power plant generator set has the advantages that the main steam pipeline is controlled through the difference between steam temperature close to a turbine main steam valve inlet and steam temperature at the outlet of the steam separator, the grasp on time is more accurate, and the thermal power plant generator set is safer in use.

Description

technical field [0001] The invention relates to the technical field of generator sets, in particular to a generator set in a thermal power plant that adopts a superheat degree to control a steam trap in a main steam pipeline. Background technique [0002] During the start-up process of the steam turbine generator set, under normal circumstances, when the load of the unit rises to 10% of the rated load or other set values, close the steam trap of the steam turbine body before the medium pressure regulating valve, and when it rises to 20% or other set values At rated load, close the drain valve of the turbine body behind the medium pressure regulating valve. Conversely, during shutdown, when the load of the unit drops to 20% of the rated load or other set values, open the trap valve of the turbine body behind the medium pressure control valve, and open the medium pressure control valve when it drops to 10% of the rated load or other set values Previous steam turbine body trap...

AI Technical Summary

Problems solved by technology

[0004] According to the above introduction, it is unreasonable to control the opening and closing of the steam trap in the main steam pipeline by the unit load, especially for large-capacity and high-parameter units, which is more of a safety hazard

[0005] Furthermore, because the metal of the main steam pipe stores more heat, it takes a long time for natural heat dissipation and cooling. If the heat stored in the insulation material is also considered, the cooling time will be longer

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