Combustion Control System Study Of Circulating Fluidized Bed Boiler

Circulating fluidized bed boiler is a new and clean firing technology;it not only has the advantages of high combustion efficiency and good fuel adaptability,but also with low pollutant emission,it’s widely applied in thermoelectricity day by day,and becomes a very important part of industrial boiler in china.Because the combustion system of circulating fluidized bed boiler has nonlinearity,time varying and large lag issues,traditional control strategy doesn’t work well on it;the operation quality is highly relied on operator’s personal experience,low automation level is very a common thing in power plant with Circulating fluidized bed boiler.This paper analyzed the characteristics of circulating fluidized bed boiler combustion system and the correlations between each control variable,simplified the complex combustion model to a 3 inputs and 3outputs model,whose inputs are primary air volume,secondary air volume and fuel content,the outputs are live steam pressure,bed temperature and oxygen content.Extract the operation data of boiler and normalize the data before using.Adopt recursive least square method to identify the parameters of three output variables’ CAR models,which under the control of same inputs.Based on the theory of generalized predictive control,establish the direct generalized predictive control model for boiler combustion system.Calculate the optimal prediction output and control law,analysis different parameters’ influence to the stability and dynamic performance of system.Then,simulate the designed system in Matlab to validate the feasibility of control plan.Select Mark Vie control system as boiler combustion optimization platform,according to related standards and safety preference,for hardware aspect,design the general network architecture between optimization system and DCS,and define communication method;complete the selection work of controller,IO modules,and power supply module,design data bus connection diagram,power distribution diagram,and terminal board diagram.For the aspects of software,complete configuration work for hardware parameters,safety protection logic and combustion optimization program in Toolbox ST;complete the development work for process diagram,control interface and control performance dashboard in Cimplicity.To support the data exchange between optimization system and DCS,complete the OPC tunnel configuration and data write test.