一种基于子空间LQG基准的MPC性能分析方法  

MPC Performance Analysis Based on Subspace LQG Benchmark

作　　者：史亚杰 田学民[1] 曹玉苹[1] 

机构地区：[1]中国石油大学(华东)信息与控制工程学院,山东青岛266580

出　　处：《华东理工大学学报（自然科学版）》2013年第6期707-712,共6页Journal of East China University of Science and Technology

基　　金：国家自然科学基金(51104175);山东省自然科学基金(ZR2011FM014)

摘　　要：为保证过程零稳态误差,过程控制器通常包含积分环节。为了考虑积分作用,针对无穷时域MPC目标函数,采用控制增量代替控制量设计LQG(Linear Quadratic Gaussian)控制器,提出一种基于子空间的LQG基准计算方法用于MPC性能分析。该方法利用过程闭环运行数据和子空间辨识算法估计子空间矩阵和噪声方差,进而求取最优LQG基准方差。在Wood-Berry二元精馏塔上的仿真验证了所提方法的有效性。An integrator is usually utilized in a process controller so as to attain the zero steady-state error. In order to consider the integral effect, this paper utilizes incremental inputs to replace control inputs in LQG controller＇s design for the objective function of the infinite horizon MPC. A novel LQG benchmark computing method based on the subspace is designed for MPC performance analysis. Both subspace matrices and noise variance are estimated by using closed-loop data and subspace identification algorithm. And then, the optimal LQG benchmark variances can be computed. Simulations via Wood- Berry binary distillation column demonstrate the effectiveness of the proposed method.

关 键 词：性能分析 模型预测控制 LQG基准 子空间辨识 方差 

分 类 号：TP274[自动化与计算机技术—检测技术与自动化装置]