Abstract: To improve the active support ability of the two major power of wind and thermal to the grid frequency,a cooperative frequency regulation control strategy of wind-thermal-storage based on multi-scale decomposition is proposed. Firstly,considering the different response time scales of wind power,thermal,and energy storage participating in the frequency regulation of power grid,a multi-scale decomposition method of frequency deviation command based on wavelet packet decomposition and a complementary matching scheme of wind-thermal-storage responding to medium,low,and high frequency components are proposed. Then,the low frequency component acquisition method of frequency deviation is proposed to adapt to the response characteristics of thermal power. And considering the constraints of active power reserve of wind farm and energy storage capacity,the self-optimal distribution method of output power of wind farm,thermal,and storage is developed to realized accurate match between wind power,thermal,and storage and medium,low,and high frequency components. Furthermore,according to different operating conditions,the cluster grouping method of wind farms based on active power reserve and intelligent distribution method of active power of wind turbines are proposed to improve the active support ability of wind farms to power grid frequency. Finally,simulation results show that the proposed strategy can effectively realize the participation of the wind-thermal-storage in primary frequency regulation,and make full use of the wind power and storage frequency regulation capacity to effectively improve the frequency characteristics of the system on the premise of meeting the constraints.