基于控制性能比较的非线性不对称系统预测控制

生产过程某些非线性系统常常表现出不对称动态特性,相对于其在工业工程中经常出现的理论研究特别是控制方法研究则十分有限。本文针对基于正反方向上的两个线性模型分别设计PID控制器的缺陷,提出根据正反方向上的线性模型分别设计相应的状态反馈预测控制器。在每一步的控制率计算中,正反方向的控制器分别计算控制作用,并通过比较正反控制器的控制性能指标来确定最终采用的控制作用。通过pH值控制的仿真实验证明其对非线性不对称系统的控制效果明显优于传统的在正反方向分别采用PID控制的控制效果。

Predictive controller for nonlinear unsymmetrical systems based on control performance comparison

Some nonlinear systems in production process always show unsymmetrical dynamic characteristics. Theoretical results for these systems,especially for its control are very limited compared with their common occurrence in industry.In this paper,state feedback predictive controller based on the positive/negative linear models was designed to handle the shortage of two separate PID controllers based on positive/negative linear models.At each step of the control law calculation,the positive/negative controllers calculated each control action.The ultimate control action was determined by the comparison of control performance index of the positive/negative controllers.Simulation of pH control showed better control performance than two separate PID controllers.