394 / 2018-12-14 14:36:42

基于光热发电系统的超临界CO2 布雷顿循环模拟及效率分析

光热；超临界 CO2；布雷顿循环；发电；效率 solar thermal energy; supercritical carbon dioxide; Brayton cycle; power generation;

全体主题 > 先进能源系统

为提高能源转化利用效率，采用过程模拟的方法，建立了基于50MWe 塔式光热发
电系统的超临界二氧化碳（sCO2）布雷顿循环回路模型，研究了是否带再热和是否带再压
的的sCO2 循环系统的布置方式和主机效率对循环效率的影响。结果表明：不带再压缩、再
热的简单sCO2 布雷顿循环效率最低。对于再压缩的布雷顿循环系统，随着压缩分流系数增
加，循环系统的效率呈现先增加、后降低的规律，存在一个效率最高点。带再压缩、再热的
sCO2 布雷顿循环具有最高的效率，在本50MWe 发电系统中，发电效率可达49.07%。主机
等熵效率对循环效率的影响成正比：sCO2 透平效率的提高，相较其他主机，能显著提高系
统循环效率。因此，在今后考虑sCO2 布雷顿循环发电系统的布置时，应首先考虑配置具有
高效率的再压缩、再热的sCO2 循环发电流程；在sCO2 循环系统主机的研发方面，应着重
提高sCO2 透平的效率，以期显著提高整个系统的发电循环效率。
In order to enhance the energy utility efficiency, the process simulation method was
adopted. The supercritical carbon dioxide (sCO2) Brayton cycle loop model based on a 50MWe
tower solar power generation system was built. Cycle loops’ efficiency with or without
recompression and reheating were studied. And the major equipment efficiencies’ effect on the
cycle loop’s efficiencies was also discussed. The results show that, simple sCO2 Brayton cycle
without recompression and reheating, has the lowest cycle efficiency. For the recompression sCO2
Brayton cycle system, with the increase of recompression split factor, the cycle efficiency raises
first and then drops. There exists a maximum value for the recompression cycle loop efficiency.
sCO2 Brayton cycle with recompression and reheating boasts the highest cycle efficiency. In this
50MWe solar power generation system, the power generation efficiency can reach to 49.07%.
Isentropic efficiency of main equipment has positive effect on the Brayton cycle efficiency. And
the sCO2 turbine efficiency’s improvement affects the cycle efficiency mostly, compared with the
compressor and recompressor efficiency’s increase. Thus, when arranging the sCO2 brayton cycle
power generation system, the high-efficiency cycle loop with recompression, reheating should be
considered first. For the research on the main equipment used in sCO2 Brayton cycle, the sCO2
turbine should be laid more emphasis on, in order to significantly improve the cycle efficiency.