Abstract: Constructing a new power system with new energy as the main body is an important means to promote the low-carbon transition of energy and power. However,due to the unreasonable dispatch of various power sources,there is a scene difficult to increase the accommodation of wind and solar energy and reduce the adjustment cost of system. In response to the above problems,this paper proposes a two-stage scheduling strategy that uses solar thermal power plant together with the traditional thermal power unit as the base load and the regulated power supply. Firstly,the first-stage scheduling model aims at maximizing wind and solar accommodation,and then obtains the dispatching output of wind power and photovoltaic power and the load to be borne by the regulated power supply. In the second stage,based on the wind power and photovoltaic dispatching output in the first stage,the lowest power generation and regulation cost of the traditional thermal power units and solar thermal power plants is taken as the goal,and the regulation capability of the solar thermal power plants is fully utilized to obtain the final dispatching output value of the traditional thermal power and the solar thermal power plants. The results of calculation examples show that the two-stage scheduling strategy proposed in this paper can effectively promote wind and solar accommodation while reducing system adjustment costs,which has certain feasibility and practical application significance.