一类非最小相位系统分层递阶多模型解耦控制器

Hierarchical multiple model decoupling controllerfor non-minimum phase systems

针对多模型控制方法中模型数目巨大,计算时间长等问题,提出了分层递阶结构多模型自适应前馈解耦控制器.该控制器中固定模型集采用分层递阶结构,基于切换准则逐层搜索最优模型,动态构造下一层固定模型集实现完全覆盖.最后一层添加自适应模型消除稳态误差.针对非最小相位系统,将系统的耦合作用视为可测干扰,采用前馈方法予以消除.最后给出全局收敛性分析.仿真结果表明,与常规多模型控制方法相比,极大地减少了固定模型的数量.而当模型数目相同时,系统的暂态响应、解耦效果得到极大改善.

To solve such problem as too many models and long computing time,a hierarchical multiple model adaptive decoupling controller is designed.It consists of fixed models with two adaptive models.The fixed models adopt a hierarchical structure:in each level,the best model is searched according to the switching index;then in next level,based on the model selected in the last level,the dynamic fixed model set is set up to cover this model accordingly.At the last stage,two adaptive models are added to eliminate the steady state error.For a non_minimum phase system,the interaction of the system is viewed as measurable disturbance and decoupled using feedforward strategy.At last the global convergence is obtained.In the simulation,compared with the conventional multiple model adaptive controller,it reduces the number of the fixed models greatly.If the same number of the fixed models is used,the system transient response and decoupling result are improved.