中国电机工程学报2016，Vol.36Issue(23)：6418-6431,14.DOI:10.13334/j.0258-8013.pcsee.151720
顶底循环参数对燃气-蒸汽联合循环全工况性能影响分析
Analysis of Topping and Bottoming Cycle Parameters on the Performance of the Combined Cycle at Design/Off-design Condition
摘要
Abstract
Based on parameters of the existing gas turbine units, the energy utilization interval for topping and bottoming cycles was repartitioned with the given turbine initial temperature, and the design/off-design performance of the combined cycle matched with three common bottoming cycle parameters was analyzed. The combined cycle with PG9351FA gas turbine was selected to be the benchmark unit, and the performances of three typical units were studied (1. Gas turbine PG9351FA with the bottoming cycle of main steam temperature of 567.5℃; 2. Increasing the design pressure ratio of compressor to 18 to match the bottoming cycle with main steam temperature of 538℃; 3. Reducing the design pressure ratio of compressor to 12.73 to match the bottoming cycle with main steam temperature of 603℃). The results show that, with higher design pressure ratio the unit exhibits a better off-design performance compared with the benchmark unit, with the efficiency increment of 0.03%~0.42%, but its net power output will decrease by 1.66%~2.72%. On the contrary, the unit with lower design pressure ratio has lower off-design performance with the efficiency decrement of 0.20%~0.39%, but its net power output will increase by 1.19%~3.27%. By the exergy analysis of topping and bottoming cycles, it can be found that the off-design performance of combined cycle mainly depends on the topping cycle. Improving the thermodynamic perfection degree of the topping cycle can enhance the design/off-design performance of a combined cycle, rather than pursuing higher parameters of the bottom cycle. At a given turbine initial temperature, the efficiency of a combined cycle will be higher at whole working condition if its performance is higher at the design condition. Thus, it can be concluded that a gas turbine combined cycle with the maximum specific work is suitable for the district with large power demand, while a combined cycle with relative higher pressure ratio is suitable for frequent peak shaving.关键词
全工况性能/联合循环/压气机改造/顶底循环变工况特性Key words
design/off-design cycle performance/combined cycle/compressor retrofit/off-design property of the topping and bottoming cycles分类
能源科技引用本文复制引用
郑炯智,张国强,许彦平,白子为,杨勇平,刘文毅..顶底循环参数对燃气-蒸汽联合循环全工况性能影响分析[J].中国电机工程学报,2016,36(23):6418-6431,14.基金项目
国家自然科学基金重点项目(51436006，51306049)；中央高校基本科研业务费专项基金(2014MS12)；国家科技支撑项目(2015BAA01B01)。Project Supported by National Nature Science Fund of China (51436006,51306049) （51436006，51306049）
Supported by the Fundamental Research Funds for the Central Universities (2014MS12) （2014MS12）
National Science and Technology Support Project (2015BAA01B01) （2015BAA01B01）
