Because of the complex structure and the large inertia of pulverizing process

the feed coal quantity of the boiler is difficult to be accurately measured

which seriously affects the regulating performance of automatic control system of the unit. Therefore

a soft measurement method of feed coal quantity is proposed for the boiler with double-inlet and double-outlet mills. Based on dynamic characteristics of the coal pulverizing system

this method establishes a soft measurement model of coal quantity of the boiler with the help of piecewise linear function by using the correlation between the pulverized coal flow rate and the key parameters such as the opening of the capacity damper

the primary air pressure and the material level

and uses the clustering algorithm to identify the relevant characteristic parameters of the soft measurement model through historical operation data of the unit. In the control system optimization project of a 330 MW unit

the real-time measurement of the feed coal quantity of the boiler has been successfully realized. This method can realize accurate measurement of feed coal quantity and effectively improve the performance of the automatic control system of the unit.