基于ＮＳＧＡ-Ⅱ算法的Ｓ-ＣＯ₂再压缩再热燃煤系统多目标优化

Taking the coal-fired thermodynamic system of S-CO₂recompression and reheat cycle as the research object, and the cycle efficiency (η_t) and levelized cost of energy (C_LCOE) as the thermodynamic and economic performance indexes of the system, the influence laws of the system key parameters on the thermodynamic and economic performance of the system were analyzed. A multi-objective optimization model of S-CO₂recompression and reheat cycle coal-fired thermodynamic system was established based on NSGA-11 algorithm. Aiming at the thermodynamic performance and economy of the system, the optimal solutions of the system key parameters were obtained. Finally, the multi-objective optimization of the system was carried out by taking reheat temperature, turbine inlet temperature, main compressor outlet pressure, reheat pressure, main compressor inlet pressure, main compressor inlet temperature and split-flow coefficient as the decision variables. Results show that the cycle efficiency and levelized cost of energy of the system increase with the increase of turbine inlet temperature and reheat temperature, thus thermodynamic performance and economy of the system cannot be optimized simultaneously. The multi-objective optimization results of η_t, and CLCoe are 53. 07% and 453. 43 yuan/(MW · h). Compared with the design condition, η_tis increased by 5. 42% and C_LCOEis decreased by 5. 91%.