Investigation On The High Valve Operation Modes Of The Dalate Power Plant 330MW Steam Turbine

The optimized management of steam turbine valves can improve the economic performance and reduce the consumption of coal.In this paper,the object of study is Huaneng Dalate Power Plant of 330 MW wet cooling unit,we are aiming at its large fluctuation range of EH hydraulic pressure and the load of valve switching,when the unit is in the operation of sequential valve.Based on the above research,this paper also studies the optimization of operation mode in high speed gate of turbine.This paper makes tests in characteristic curve with the object of 3# unit in Dalate Power Plant,and acquires the actual operation data under different working conditions.According to the collected data,we carry on analysis of actual operating parameters and steam distribution,including valve opening,steam pressure,temperature and vibration changes.There is a great deviation from the linearity of the comprehensive flow characteristic curve obtained by the valve to that of the ideal valve comprehensive flow characteristic curve,it indicates that working efficiency of the turbine has been seriously reduced and economic performance of the unit also be affected.With uniform inlet and rotating shaft torque evenly distributed in turbine main shaft and the shaft as the principle,we analyze existing problems of tone curve of unit in stea m admission,installation debugging,curve design and steam distribution designation,an d determines the basic process of transformation.According to the optimization and ident ification theory of overlap degree,the implementation plan is determined and reformed.The existing problems have been solved after the reconstruction of unit,and the sing le or sequence valve could be switched freely,the monitoring indexes of the unit could al so meet the requirements of the unit power generation.After valve management optimiza tion,the temperature and vibration of the unit in a sequential valve mode basically keep t he same range within the single way valve,EH oil pressure fluctuation range also decreas ed significantly.There is no fluctuation of load during the switching of single / sequence valve in the unit.And the economy of the unit has been improved.Usually,the generator load generates in the range of 230-330 MW,and the efficiency of high pressure cylinder o f operating unit is increased by about 1% when single switches to sequential valve after t he implementation of key management unit optimization,in the meanwhile,reducing the coal consumption about 0.7g.In conclusion,the strategies of this paper have remarkable economic and social benefits when the unit is under the same power generation.