Abstract: To enhance the regulation flexibility of thermal power units under the new power system, a full-process coupling scheme for frequency regulation of thermal power unit coupled with a molten salt system integrating a multi-heat-source thermal storage mode was designed. In this scheme, the multi-heat-source thermal storage mode of the electric-heating molten salt heat exchanger and extraction steam thermal storage was integrated, and a thermal release and utilization route based on molten salt heating the feedwater of the high-pressure heater was proposed. A dynamic model of the coupled system was established, and verification was carried out using actual data. Aiming at the full thermal storage and release process of the coupled system, a control strategy for the molten salt system coupled with thermal power units based on modal increment matching was proposed. Simulation results show that during load decrease process, under the mode of integrating multi-heat-source thermal storage, the system load stabilization time is shortened by 38.66% compared with the system without molten salt thermal storage, and the comprehensive ramping performance indicator is improved by 29.49% compared with the system with only extraction steam thermal storage. During load increase process, the proposed strategy based on power increment can effectively decouple the mutual influence between the thermal power unit and the molten salt thermal storage system. Compared with the high-pressure heater throttling scheme and the no-thermal-storage scheme, the comprehensive ramping performance indicator is increased by 15.01% and 21.18% respectively.