Deep peak regulation heat supply method based on CFB heat supply unit

A deep peak regulation heat supply method based on CFB heat supply units comprises the following steps that two coal feeders corresponding to a coal inlet in the middle of a boiler hearth are stopped, the output of other coal feeders is increased, the total coal feeding amount is kept unchanged, NOx emission can be reduced, and meanwhile the electric load of each unit can be reduced by 1 MW; on the basis that a unit enters deep peak regulation, the enthalpy value of steam entering a high-pressure cylinder and a medium-pressure cylinder of a steam turbine is reduced by increasing the desuperheating water amount of a superheater and a reheater, and then the purposes of reducing the power generation output of the unit and achieving ultra-deep peak regulation are achieved. After a unit enters deep peak regulation, the electrical load is stabilized at about 30MW, the bed temperature of a CFB boiler is reduced through coal conveying combustion adjustment, and the main reheat steam temperature is further reduced by