JERAJournal of Electronic Research and Application2208-35022208-3510Bio-Byword Scientific Publishing Pty. Ltd.10.26689/JERA.v10i9.15925ArticleSelection of Technical Routes for Flexible Retrofit of Thermal Power Units Under the New-Type Power Systemhttps://artdesignp.com/journal/JERA/10/9/10.26689/JERA.v10i9.15925WangYongxue,ZhengLijun,FengYiwu20261092026-10-30Against the background of new‑type power system construction, large‑scale grid‑connection of wind and solar power creates prominent peak‑shaving gaps in the power system. Constrained by the “power‑determined‑by‑heat” principle, conventional combined heat and power (CHP) units have limited accommodation space for new energy. This paper sorts out six mainstream heat‑power decoupling retrofit schemes, and elaborates the retrofit principles and equipment composition of each technology combined with system schematic diagrams and retrofit flow charts. Taking a 300 MW heating extraction‑condensation unit as an engineering case, four typical retrofit technologies are selected, and comparative analysis on energy‑saving and economic benefits is carried out through quantitative indicators. The results show that the composite coupling scheme of low‑pressure cylinder zero‑output plus hot‑water heat storage delivers the best comprehensive benefits, and multi‑technology collaborative retrofit represents the mainstream direction for unit flexibility upgrading. The research conclusions can provide data support and decision‑making reference for technical‑renovation demonstration and scheme argumentation of thermal power plants.New‑type power system, Thermal power unit, Flexible retrofit, Heat‑power decoupling, Deep peak shaving, Technology selection

[1]       National Energy Administration, 2018, Technical Guidance Document for Flexible Retrofit of Coal-Fired Power Units. [2]       Zhang S, Sun C, Yu L, et al., 2023, Review on Research Progress of Flexible Retrofit for Coal-Fired Power Generating Units. Southern Energy Construction, 10(2): 48–54. [3]       Zhang L, 2025, Coal-Fired Power Transformation Path and Flexible Retrofit Development Trend Under New-Type Power System. Power Grid and Clean Energy, 41(1): 89–95. [4]       Ouyang Z, Wang H, Lü Q, et al., 2023, Progress in Deep Peak-Shaving Technologies for Pulverized-Coal-Fired Power Generating Units. Proceedings of the Chinese Society for Electrical Engineering, 43(22): 8773–8789. [5]       Wang Z, Chen K, 2022, Review on Domestic Research Status and Development Trend of Heat-Power Decoupling Technologies. Electric Power Construction, 43(3): 68–76. [6]       Wang Z, Huang Q, Liu G, et al., 2024, Safe Operation Strategies for Peak-Shaving Thermal Power Units Adapted to New-Type Power System. Southern Energy Construction, 11(6): 33–40. [7]       Duan Q, 2022, Research on Key Control Technologies for Flexible Thermal Power Units. Shanxi Electric Power, 2022(6): 36–39. [8]       Liu J, Li Y, Song Z, et al., 2022, Flexible and Intelligent Coal-Fired Power-Generation Technologies and Evaluation System. Journal of Power Engineering, 42(11): 993–1004 + 1012. [9]       Huang W, Jiang Y, 2022, System Design and Operation Characteristics of Low-Pressure Cylinder Zero-Output Retrofit for 300 MW Units. Journal of Thermal Energy and Power Engineering, 37(6): 104–111. [10]     Shan Z, 2024, Research on Timing Decision Optimization of Low-Carbon Technology Investment for Thermal Power Under Carbon-Budget Constraints, thesis, North China Electric Power University. [11]     Sun J, Wu H, 2023, Waste-Heat-Recovery and Peak-Shaving Capacity Test for Units With High-Back-Pressure Dual-Rotor Retrofit. Turbine Technology, 65(1): 53–56. [12]     Ma J, Deng W, 2023, Optimization of Safe-Operation Control Strategy for Reheat-Bypass Heating Systems. Power-Station System Engineering, 39(2): 37–40. [13]     Chen Y, Liu Y, 2023, Quantitative Analysis on Thermal Loss of Steam-Bypass Heat-Power Decoupling. Electric Power Engineering Technology, 42(2): 90–96. [14]     Zhu X, Li L, 2023, Research on Peak-Shaving Characteristics of Thermal Power Units Coupled With High-Voltage Electrode Electric Boilers. Thermal Power Generation, 52(9): 132–138. [15]     Yang W, 2024, Comparative Calculation of Coal-Consumption Characteristics Under Different Heat-Power Decoupling Schemes. Energy-Saving Technology, 42(2): 145–150. [16]     Zhou Q, Yao Y, 2023, Simulation on Diurnal Peak Shaving of CHP System Coupled With Hot-Water Heat Storage. Energy Storage Science and Technology, 12(5): 1642–1650. [17]     Pang L, Zhang S, Duan L, 2021, Research on Improving Flexibility of Re-Heat Units Using High-Temperature Molten-Salt Energy Storage. Proceedings of the Chinese Society for Electrical Engineering, 41(8): 2682–2691. [18]     Guo H, Tian F, 2024, Engineering Application of Absorption Heat-Pump for Circulating-Water Waste-Heat Recovery Retrofit. Auxiliary Equipment for Power Stations, 45(1): 41–45.