Large-scale renewable energy consumption and low carbon development of power systems have a higher needto reduce carbon emissions in the peak frequency modulation of thermal power units. To improve the economicalefficiency of the system and the low carbon of the thermal motor peak adjustment, this paper proposes a hierarchicaloptimal scheduling method of the thermal storage considering the thermal power unit's heat storage transformation andoptimal solar energy abandonment. Considering the reverse peak adjustment characteristics of wind, an optimalenergy-discarding constraint model is established, and an upper model is constructed to minimize the net load variance ofthe power grid. The net load curve is "peak-clipping". To expand the peak-shaving depth of thermal power units, a carbontransaction cost model is established considering the transformation of heat storage units. From this, the lower layermodel is established with the goal of minimizing the total system cost and carbon transaction cost. A collaborativeoptimization of system economy and low carbon is realized while the net load curve is "peak-cutting and valley filling"twice. The rationality and validity of the proposed model are verified by an example.