Thermal power plant's energy cascade utilizes system

The utility model relates to a thermal power plant's energy cascade utilizes system, the system includes: main turbo generator set, back pressure type small steam turbine, wherein main turbo generatorset includes high school, the pressure jar of coaxial setting, the low pressure jar, and the generator, the exciter, the play steam ports of height, intermediate pressure cylinder and the steam inletof low pressure jar are said through first defeated steam pipe and are communicate, the play steam ports of height, intermediate pressure cylinder and back pressure type small steam turbine's steam inlet pass through the defeated steam pipe way intercommunication of second, back pressure type small steam turbine drive station service generator, exciter, station service generator respectively theelectricity connect the station service electrical system, exciter, station service generator respectively and be equipped with the circuit switch between the station service electrical system, the defeated steam pipe of first