The Research Of Soft Sensing Technology Of Drum Level Based On Model

The soft sensing technology is applied to drum level measurement in power plant. According to the basic relation of substance balance and energy balance, this paper analyzes drum level dynamics into the result of changes the amount of saturated water and saturated steam in the drum. A method is being researched for structural heat signal by means of known amount of air flow, together with the oxygen content in the flue gas; the calculated method of the heat flow to the risers based on the enthalpy difference, which feed water from the outlet of the coal economizer absorbing the amount of heat through the water wall tubes changes saturated steam. Statistic results indicate that there are some relations between structural heat signal and the heat flow to the risers. Finally, a soft sensing model for drum-boilers level based on mechanism analysis and data statistic analysis is constructed. Experiment results show that the output of soft-sensing model fits well with the real drum level dynamic.