With the gradual increase in the proportion of new energy in the energy system

increasing the difficulty of AGC frequency regulation of thermal power units

energy storage systems combined with thermal power units AGC frequency regulation technology in China's power industry is developing rapidly. In this paper

the joint frequency modulation system of thermal power unit and energy storage system is studied for the problem of not considering the characteristics of unit variable load process and the lack of relevant evaluation system. Firstly

the thermal unit coal consumption

lifetime

environmental friendliness and energy storage lifetime models are established and uniformly transformed into cost terms during the thermal unit variable load process

thus constituting the corresponding evaluation system. Secondly

the system day-ahead operation optimization model is established

and the system load allocation strategy is further refined by considering the optimization results. Finally

the method proposed in this paper is verified by a case study. The results show that the optimal allocation strategy of joint frequency modulation load of thermal power unit and energy storage proposed in this paper can achieve the purpose of energy storage state management; and through the optimal selection of unit variable load rate and the coordinated response with the energy storage system

the process of unit load change is alleviated the problems of excessive environmental protection and rapid loss of lifespan.