TY - EJOU AU - Chi, Shidan AU - Luan, Tao AU - Liang, Yan AU - Hu, Xundong AU - Gao, Yan TI - Exergy Analysis and Thermal Optimization of a Double-Turbine Regeneration System in a Ultra-Supercritical Double-Reheat Unit T2 - Fluid Dynamics \& Materials Processing PY - 2021 VL - 17 IS - 1 SN - 1555-2578 AB - Improving the primary steam parameters is one of the most direct ways to improve the cycle efficiency of a power generation system. In the present study, the typical problem connected to the excessively high superheat degree of extraction steam in an ultra-supercritical (USC) double-reheat unit is considered. Using a 1000 MW power plant as an example, two systems (case 1 and case 2) are proposed, both working in combination with a regenerative steam turbine. The thermal performances of these two systems are compared with that of the original system through a heat balance method and an exergy balance strategy. The results reveal that the two coupled systems can significantly reduce the superheat degree of extraction steam, turbine heat rate, and coal consumption of the unit and improve the energy utilization efficiency. These results will provide useful theoretical guidance to future investigators wishing to address the general problem relating to energy conservation and modelling of the coupled extraction steam regenerative system of USC double-reheat units. KW - Ultra-supercritical unit; exergy loss; thermal performance; regenerative steam turbine; superheat degree DO - 10.32604/fdmp.2021.013178