In order to meet the demand of rapid response of coal pulverizing system for flexible peak shaving of thermal power units under wide load, aiming at the problem that the dynamic simulation model of ZGM medium speed pulverizer is not accurate enough under wide load conditions, a dynamic mechanism model is established based on the law of conservation of mass and energy. Local sensitivity analysis is used to determine the key parameters (primary air volume, air temperature and heat factor). Combined with the heat balance mechanism, the latent heat and heat dissipation model of vaporization is modified. The results show that the simulation error of the modified model is less than 5% in the wide load range of 40%-90%. On this basis, aiming at the problem of fuel supply lag caused by the start-up window period of the coal pulverizer during the rapid load-raising process, the nonlinear effects of coal feeding slope rate, primary air volume and primary air advance time on key parameters such as response time of pulverized coal output and outlet temperature are analyzed. The grid search multi-parameter optimization is used to obtain the optimal parameter combination method for improving the output of the operating coal pulverizer, which can shorten the response time of pulverized coal flow to 300 s at low load and 350 s at high load, which is about 3.6 min earlier than the start-up mode of the coal pulverizer, and the outlet temperature fluctuation meets the safety constraint requirements. This study provides a reliable model basis and optimal operation scheme for accurate simulation of wide load and rapid variable load operation of coal mill.

To address the mismatch between thermal and electrical loads in coal-fired combined heat and power generation units during heating seasons, and the operational discrepancies between heating/non-heating periods, this study proposes a molten salt thermal energy storage system with a bidirectional heat exchange configuration. During heating seasons, the system operates in “main/reheat steam charging-feedwater discharging” mode to enhance operational flexibility and satisfy district heating demands, and in non-heating seasons, it adopts “main/reheat steam charging-feedwater/condensate cooperative discharging” mode to improve thermal efficiency. Simulation results demonstrate that the bidirectional heat exchange architecture enables flexible switching between charging/discharging modes, achieving a minimum electrical load of 98.76 MW_e (28.2% of turbine heat acceptance (THA) rating) at 90 MW_th heating demand during heating seasons, and 106 MW_e (30.3% THA) with 80% main steam extraction ratio in non-heating seasons. Economic evaluation reveals a 12.3% reduction in capital costs compared to conventional molten salt systems during heating operation. The research validates the effectiveness of bidirectional thermal storage-exchanger configurations in enhancing whole-lifecycle economic performance and energy efficiency, providing technical support for low-carbon transition of thermal power units through operational flexibility improvement and energy cascade utilization optimization.