600MW Steam Turbine Performance Diagnosis

As China's coal-fired power units are moving towards high-parameter and high-capacity trends,600MW power unit has gradually become the main power supply.The safety and economy of power unit has become issue of great concern.The steam turbine is the core of the whole plant equipments,while is the focus and difficult of condition monitoring and fault diagnosis in power plants.Based relative internal efficiency and flow capacity,while are two important indexs that reflect the turbine economy and security,a systematic study of relative internal efficiency factors model on 600MW steam turbine flow passage is set up,and the influencing factors are analyzed qualitatively.According to the principle of thermodynamic calculation of turbine,detailed thermal calculation model is based on tool of VB6.0 combined with Microsoft Excel and used to find out how cylinder efficiency,coal consumption rate and heat consumption rate change as the steam leakage between stages happens.Besides,the paper made a theoretical analysis of the flow capacity of the nozzle.When reheater first stage wears,the internal efficiency of the changes is calculated.So these results can provide a theoretical basis for the 600MW steam turbine performance diagnosis.