Wide-load high-efficiency steam turbine unit provided with high-pressure cylinder comprising sub-cylinders arranged coaxially

The invention relates to a wide-load high-efficiency steam turbine unit provided with a high-pressure cylinder comprising sub-cylinders arranged coaxially. The wide-load high-efficiency steam turbineunit is correspondingly connected with a boiler, a heater and a steam condenser; the steam turbine unit comprises a high-pressure cylinder, a medium-pressure cylinder and a low-pressure cylinder whichare connected in sequence; the high-pressure cylinder is correspondingly connected with a main steam pipeline of the boiler, a cold reheat steam pipeline of the boiler and the heater; the pressure cylinder is divided into two cylinders which are correspondingly a cutoff high-pressure cylinder and a retained high-pressure cylinder which are arranged coaxially; when the load is higher than a set threshold value, the two high-pressure cylinders simultaneously implement steam input work; when the load is lower than the set threshold value, the cutoff high-pressure cylinder is cut off, but the cutoff high-pressure cylinder