Real-time online acquisition method for combustion state of hearth

The invention relates to a real-time online acquisition method for the combustion state of a hearth. The real-time online acquisition method comprises the following steps of 1) the boiler steam-waterside measurable operation data and the coal amount instruction data corresponding to the current moment in a DCS system are acquired; 2) the effective heat absorption amount corresponding to the current moment is estimated according to the boiler steam-water side measurable operation data; 3) the total coal amount of the inlet furnace corresponding to the current moment is estimated according to the coal amount instruction data; 4) a hearth combustion economical index corresponding to the current moment is acquired according to the obtained effective heat absorption and the total coal amount of the inlet furnace; and 5) off-line identification is performed on the dynamic characteristic parameters of the power generating process of a thermal power generating unit. According to the real-timeonline acquisition method