The Mathematical Model Established For The Optimal Control Of The Coal-water Ratio In The Supercritical Boiler.

The control of superheated steam is an important topic about the supercritical boiler. Based on the designed data of a 600MW supercritical boiler, and the calculation procedure of thermal characteristic in subcritical boiler, the paper established a calculation procedure of thermal characteristic for the supercritical boiler circuit. Analysis the adjustment of the center point temperature and superheated steam temperature at the condition the coal changes, strengthen the cognition that the input heat from the fuel should match the heat that medium required, calculate and analysis the affect from the change of running condition on the control of the superheated steam temperature, emphasis on the effect from the characteristic of fuel, excess air ratio, the water temperature in economizer inlet and boiler load, and bring up a new method for the control of superheated steam. Analysis the effect on the boiler's safe from the dynamic characteristics of water and does the try to brought PID control algorithm to the control of superheated steam.