Study on Performance On-line Monitoring Method for Turbine Driven Boiler Feed Pump Set
|School||Tohoku Electric Power University|
|Keywords||boiler feed pump auxiliary turbine the efficiency of the feed pump therelatively internal efficiency the efficiency of low pressure cylinder|
Currently, the on-line monitoring method for the turbine driven boiler feed pumpset are carried out by capturing the relative dates in this partial thermodynamicsystem, which cannot be used to analyze the relevance and iMPact of the operatingperformance between the main engine and the turbine driven boiler feed pump set.Taking this insufficient into consideration, we pointed out the Three ThermodynamicSystems Method to monitor the operating performance of the turbine driven feedpump set.First of all, the water supply system of the power plant is analyzed in this thesis,and the configuration model of the boiler feed pump and its prime mover ere alsosummarized.Secondly, the comprehensive mass balance and energy balance analysis of thethree thermal systems are proceeded, namely the steam turbine, the low pressurecylinder-low pressure regenerative system and the turbine driven boiler feed pump.And by solving the simultaneous equations of the first two thermal systems we canascertain the feed-water enthalpy rise, which is converted from the shaft power of thefeed pump. Afterthat, the shaft power of the feed pump and the output power of theauxiliary turbine could be determined, and by analyzing the third thermal system wecan work out the input and output powers of the turbine driven feed pump set. Thenthe efficiency of the turbine driven feed pump set, the efficiency of the feed pump andthe relative internal efficiency of the auxiliary turbine are calculated, which can beused to monitoring the operating performance of the turbine driven feed pump set.Meanwhile, from the above calculation, we have obtained the output power ofauxiliary turbine, so we can determine the exhaust steam cold source loss of theauxiliary turbine in the condenser. Then we can determine the exhaust steam coldsource loss of the low pressure cylinder in the heat balance calculation of the condenser by analyzing the thermal system of the condenser; combining with the flowcalculation formula of the exhaust steam in the low pressure cylinder we candetermine its exhaust steam enthalpy which would be used to obtain the relativeinternal efficiency of low pressure cylinder.Finally, based on the thermodynamic parameters and operating data of thethermal system in one660MW power unit which act as the domastic representative,the said method ere applied to conduct the calculations of the operating performanceand the efficiency of the low pressure cylinder. The results affirm the validity of thenew method which should be promoted in the engineering practice.