Dynamic modeling and intelligent heating strategies of district heating system based on the standardized thermal resistance

The intelligent heating system can improve heating efficiency and promote renewable energy accommodation that positively affects the realization of the dual-carbon strategy. This paper dynamically modeled the key components based on the standardized thermal resistance defined by the inlet temperature difference and constructed the overall dynamic heat current model of the heating system from the heat source to the user. The dynamic model simultaneously and comprehensively reflects the heat transfer, storage, and delay characteristics of the heat exchanger, piping, and building. On this basis, an iterative method is proposed and used to develop various heating strategies for the hourly quality regulation of the primary heating network. The proposed user-following heating strategy has the greatest energy-saving potential of 25.27% compared with the all-day heating strategy. Moreover, based on the user-following heating strategy, we proposed five different heating strategies, namely all-day constant heating type, inverted triangle type, stair-step type, trapezoid type, and parabolic type, to achieve energy-saving operation of the heating system for the actual application. The trapezoid type has the highest energy-saving ratio of 9.41% compared to the all-day constant heating type. In all, this standardized thermal resistance-based dynamic modeling method and the proposed heating strategy provide a new theoretical basis and solutions for the intelligent heating system.