A Method for Preventing Power Oscillation in Full Stroke Activity Test of Main Steam Valve of Steam Turbine

Abstract

The present invention discloses a method for prevention of generation of power oscillation in a process of a main stop valve full-stroke test of a steam-turbine generation steam turbine. On the basisof the prior art, a determination module a and an alarm device are added to achieve removal of a power control loop, effectively prevent a unit from generating power fluctuation and power oscillationad emit an acousto-optic alarm after a steam turbine set is large in load deviation; a load deviation function is added to achieve that a high-pressure control valve can be switched on and off at variable speeds and reduce a small steam turbine load fluctuation amplitude; and a determination module b and a valve location manual input module are added to achieve a unit valve location maintenance function and a manual input valve location value function and effectively prevent the unit to generate power fluctuation and power oscillation. The method for prevention of generation of power oscillation in a main stop valve full-stroke test of a steam turbine provides a great guarantee for normal and smooth performing of the main stop valve full-stroke test of the steam turbine, and effectively reduces operators' burden.

Description

technical field [0001] The invention belongs to the technical field of thermal power generation, and in particular relates to a method for preventing power oscillation during a steam turbine for steam turbine power generation during a full stroke activity test of a main steam valve. Background technique [0002] During the load operation process of the large-capacity steam turbine belt, the load lifting of the steam turbine is realized through the switch of the high-pressure regulating valve GV. High-pressure main steam valve TV, medium-pressure main steam valve RSV and medium-pressure regulating valve IV remain fully open for a long time, and they are in a high-temperature and high-pressure environment for a long time, so it is easy to deposit oxides on the valve stem or valve sleeve gap At the same time, high temperature creep will cause problems such as bending of the steam valve stem and deviation of the center of the valve body. The steam turbine speeding accident caus...

AI Technical Summary

Problems solved by technology

[0016] The main causes of accidents caused by the activity test of the high-pressure main steam valve are as follows: 1. The setting of the high-pressure regulating valve position balance module is unreasonable; 2. The closing speed of the high-pressure main steam valve activity test is too fast; 3. The parameter setting of the power control circuit is improper ; 4. Unreasonable selection of test steam parameters

Measures currently taken and existing risks: 1. Since the full-stroke activity test of the main steam valve of the steam turbine brings relatively high risks, ranging from parameter fluctuations to serious tripping, many power plants only conduct part-stroke activity tests of valves. Or just perform a full stroke motion test before shutting down

2. In order to maintain the stability of the steam turbine load, when the power control circuit is put into operation, the valve activity test time is generally extended, which has a greater impact on the boiler combustion control under high load

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