Deep peak-shaving and efficient operation control system and method for thermal power unit with variable turbine speed

A deep peak-shaving and efficient operation control method for a thermal power unit with variable turbine speed, applied to an operation control system, the deep peak-shaving and efficient operation control method comprising:

• S1:
• starting a rotor of a turbine to a safe operating speed range;
• S2:
• adjusting a load to a target load and maintaining an opening of an inlet main steam valve to match a turbine speed of the turbine;
• S3:
• determining whether the inlet main steam valve is fully open, if not, gradually increasing the opening of the inlet main steam valve, reducing the turbine speed while the target load is maintained unchanged until the inlet main steam valve is fully open;
• and if yes, keeping up an operation of the turbine, wherein the turbine is coaxially and directly connected to a generator, and the generator is configured to change a flow passage rate of the turbine to achieve no throttling of the inlet main steam valve based on a speed adjustment of the turbine speed;
• and
• S4:
• turning off the turbine:
• first reducing a main steam pressure to lower the load of the generator, and then gradually reducing the opening of the inlet main steam valve until the turbine is safely and stably shut down.