The invention discloses a method and 
system for optimizing starting and stopping of a thermal power 
generating unit in a wind-solar-thermal storage 
system, and relates to the technical field of wind-solar-thermal storage resource optimization. The method comprises the following steps: determining the power generation amount of a thermal power 
generating unit in each preset time period according to the obtained 
wind power historical power generation amount, photovoltaic historical power generation amount, 
power grid historical demand, a preset energy use principle and a preset constraint condition in each preset time period all the year round; calculating the minimum annual investment and operation cost of the thermal power 
generating unit under a group of preset constraint conditions and a corresponding starting 
state sequence of the thermal power generating unit according to the 
generating capacity of the thermal power generating unit; the method comprises the following steps: acquiring a plurality of minimum annual investment and operation costs and a starting 
state sequence by adjusting a preset constraint condition, and selecting the annual minimum investment and operation cost with the minimum cost and the corresponding starting 
state sequence of the thermal power generating unit from the plurality of minimum annual investment and operation costs; according to the scheme, accurate shutdown or startup of the thermal power generating unit is realized, the operation cost of the thermal power generating unit is reduced, and the 
utilization rate of wind and light resources is improved.