超超临界机组配置优化经济性分析

Economic Analysis of Ultra-supercritical Unit after Configuration Optimization

分析当前主流的节流配汽机组宽负荷运行经济性低的原因,参考高压缸分列布置的新型配置方法对机组进行改造,并建立了APROS仿真模型,研究优化后机组适应宽负荷运行的策略。与改造前机组相比,在68.8%THA(切缸工况)热耗率降低151kJ/(kW·h),节能效果显著。分别采用热量分析法和分析法两种方法对优化后系统进行经济性分析,通过调阀开度与综合阀门节流效率的关系以及主汽压力和循环效率的关系,建立了机组对应工况下热耗率的计算模型。对优化后机组进行分析,整体损失比原机组减小35MW,效率提升的部位主要在锅炉、加热器和凝汽器。

The reason for the low economical efficiency of the throttling steam distribution unit in wide load operation was analysed.Based on a new configuration method of high pressure cylinder arrangement,the model and simulation of the new unit were carried out based on APROS platform,and the strategy of the optimized unit adapting to wide load operation was studied.Compared with the reference unit,the heat consumption rate is reduced by 151kJ/(kW·h)in the cylinder cutting condition,and the energy saving is obvious.From the thermal analysis method and the exergy analysis method,the optimized system was analyzed economically,and the heat consumption rate calculation model was established.Through the relationship between the valve opening with the comprehensive valve throttling efficiency,and the relationship between the main steam pressure with the cycle efficiency,the heat consumption rate corresponding to the working condition can be directly obtained according to the above-mentioned relational model.An exergy analysis of the optimized unit found that the overall exergy loss is 35MW smaller than that of the reference unit,and the parts where the exergy efficiency is improved are in the boiler,heater,and condenser.