基于多模型的循环流化床锅炉床温预测控制  

Predictive Control on Bed Temperature of CFB Boilers Based on Multiple Models

作　　者：董湛波[1] 向文国[1] 王新[1] 

机构地区：[1]东南大学能源与环境学院,南京210096

出　　处：《动力工程学报》2011年第3期181-186,共6页Journal of Chinese Society of Power Engineering

基　　金：国家科技支撑计划资助项目(2006BAA03B04);国家高技术研究发展863计划资助项目(2009AA04Z158)

摘　　要：针对循环流化床锅炉床温的强非线性特性,提出了一种改进的基于多模型的预测控制策略.将多模型控制策略和广义预测控制相结合,采用几个典型工况点的模型来逼近整个运行区间的动态特性,从而取代在线辨识来校正模型.通过跟踪实际工况的变化来对各个子控制器进行加权以获得合适的控制增量,并对广义预测控制的性能指标进行了修改,以消除调节后期的振荡.典型工况点的模型可由离线辨识得到,参数恒定,使得丢潘图方程和控制规律式的求解可以离线进行,降低了在线计算量.将该算法用于某电厂440 t/h循环流化床锅炉的床温控制系统仿真,结果表明:该算法能够很好地克服被控对象的非线性,在负荷大范围变动时仍然可以取得良好的控制效果.Aiming at the strong nonlinearity features of the bed temperature of circulating fluidized bed（CFB） boilers,a modified predictive control scheme based on multiple models has been proposed,which combines multi-model control with generalized predictive control,and uses models of several typical operating points to approach the dynamic characteristics of the total range of operating points,so as to correct models instead of on-line identification.By tracing the change of actual working conditions for weighting of local controllers,appropriate control increment is obtained,while the object function of generalized predictive control modified so that the oscillation at later stages can be eliminated.The models of typical operating points are identified off line,of which the parameters are generally constant,so that solution of Diophantine equation and calculation of control law can be done off-line,resulting in reduced amount of on-line calculation.The algorithm was applied to the bed temperature control of a 440 t/h CFB boiler.Simulation results demonstrate that the control method may effectively overcome the nonlinear shortcoming of the controlled object,via which better control effect may be obtained even under large variations of load.

关 键 词：循环流化床锅炉 床温 广义预测控制 多模型 在线辨识 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]