Plant-level AGC system control method for coal-fired power plant

The embodiment of the invention provides a control method for a plant-level AGC system of a coal-fired power plant, and belongs to the field of power plant operation. The method comprises the following steps: in response to a received plant-level load instruction, obtaining a whole power plant output upper limit power value and a whole power plant output lower limit power value obtained according to in-plant unit output upper and lower limit calculated values; if the plant-level load instruction, the output upper limit power value of the whole power plant and the output lower limit power value of the whole power plant meet a first preset condition, obtaining an actual output value of each unit in the current operation of the power plant and an operation state of an auxiliary machine corresponding to the unit; the actual output values of the units in the operation of the power plant and the units with the operation states of the auxiliary machines in the units meeting a second preset condition are used as load