基于能耗敏感性的超超临界660 MW汽轮机经济性分析

Economic Analysis of an Ultra-supercritical 660 MW Steam Turbine Based on Energy Consumption Sensitivity

以上汽N660-25/600/600型汽轮机为研究对象,采用汽轮机定功率变工况计算方法,对汽轮机高压缸、中压缸及低压缸进行能耗敏感性定量分析,得出通流效率变化对汽轮机热耗率的影响规律。根据锅炉热效率及厂用电率设计值计算额定工况下通流效率对机组发电煤耗及供电煤耗的影响。结果表明:高压缸效率每下降1%,不同负荷工况下热耗率增加11. 04～12. 80 kJ/(k W·h);中压缸效率每下降1%,能耗敏感性介于21. 02～22. 77kJ/(k W·h);低压缸效率每下降1%,能耗敏感性介于23. 42～24. 68 kJ/(k W·h);在通流部分中,低压缸能耗敏感性最大。

The Shanghai Electric-Siemens ultra-supercritical 660 MW steam turbine has a large propor-tion in the newly produced 600 MW units in China in recent years because of its superior performance in-dex. It has become an important development direction of 600 MW level ultra-supercritical power genera- tion technology. With a Shanghai electric N660-25/600/600 steam turbine as an example,the quantitative analysis of energy consumption sensitivity of the high-pressure cylinder, medium-pressure cylinder and low-pressure cylinder were carried out based on the calculation method of rated power and variable condi-tions ,the influence of each cylinder efficiency change on the heat consumption rate of steam turbine is ob- tained. The results show that for this type of turbine, the heat consumption rate increases by 11 ? 04 ? 12. 80 kJ/(kW ? h) under different load conditions for every I percentage point reduction in the efficien- cy of the high-pressure cylinder. The energy consumption sensitivity is between 21 ? 02 ?22.77 kj/ ( kW ? h) for each percentage point reduction in the medium-pressure cylinder efficiency. The energy consumption sensitivity of low-pressure cylinder is between 23.42 ?24.68 kJ/(kW ? h) for every I percentage point reduction in the efficiency of low-pressure cylinder. That of the low-pressure cylinder is the greatest in the whole flow-through section.