Steam turbine barring cooling system and method thereof

The invention relates to a steam turbine barring cooling system and method in the technical field of steam turbine cooling. The steam turbine barring cooling system comprises a high-pressure cylinder, an intermediate-pressure cylinder, a low-pressure cylinder, a control valve, a controller and a condenser. The control valves comprise the first control valve and the second control valve, the first control valve and the second control valve are electrically connected with the controller, the first control valve communicates with the high-pressure cylinder, the second control valve communicates with the intermediate-pressure cylinder, and the condenser communicates with the high-pressure cylinder and the low-pressure cylinder. After the controller controls the first control valve to be opened, under the vacuum negative pressure of the condenser, low-pressure gas sequentially passes through the first control valve and the high-pressure cylinder and then enters the condenser. After the controller controls the seco