MIMO非线性系统的多模型建模方法

针对实际工业过程中多变量系统存在着非线性、工况范围广的特点,本文提出了一种新的多模型建模方法.首先对系统调度变量进行满意模糊c均值聚类,在此基础上采用基于加权性能指标的多模型辨识算法辨识多模型系统,得到的模型在全局拟合与局部特性之间取得良好的权衡,同时能得到每个局部模型的适用域.以典型pH中和过程为对象,采用上述建模方法建立其系统多模型,仿真结果验证了该建模方法的有效性.

A Multi-Model Modeling Approach to MIMO Nonlinear Systems

For real industrial processes in which systems are multi-input multi-output (MIMO),nonlinear and large operating range,a new multi-model modeling approach is presented in this paper.Firstly,a set of scheduling variables is partitioned into c subsets by Satisfactory Fuzzy c-mean Clustering algorithm,then the multi-model system is identified by the identification algorithm based on weighted performance function.The resulted model can obtain good trade-off in terms of global fitting and local interpretation.For each local model,its valid area is got as well.The result of application with the modeling approach to typical pH process illustrates the performance of the proposed algorithm.