Frequency modulation method and system for fused salt energy storage coupling thermal power generating unit

The invention provides a frequency modulation method and system for a fused salt energy storage coupling thermal power generating unit. The method comprises the following steps: decomposing a power grid frequency modulation response demand through a VMD algorithm to obtain a residual component and a plurality of modal components; calculating adjacent aliasing degrees of all modal components, and dividing a high-frequency modal component group and a low-frequency modal component group based on the minimum value of the adjacent aliasing degrees; if the high-frequency modal component group only comprises one modal component, the residual component and the multiple modal components are equally divided into a high-frequency group and a low-frequency group according to the center frequency, and multiple fusion modes are adopted for the modal components in the high-frequency group to obtain different fusion components; calculating a ratio of each fusion component to a power grid frequency modulation response demand