兼顾经济与控制性能的过程分程控制系统结构设计

Split-range Control Configuration Design Considering Economic and Control Performance

随着流程工业对于降低成本和提高收益等经济性能要求的不断提高,希望控制系统在操纵变量对被控变量实施控制的同时尽可能减小对操作费用的影响。对于非方胖系统,由于操纵变量维数多于被控变量维数,当被控变量偏差较小时期望采用对经济性能影响小的操纵变量进行控制,只有当被控变量偏差较大、无法满足控制要求时,才期望将对经济性能影响大、响应速度快的操纵变量投入控制。对此,传统的单回路控制结构不能满足过程控制问题的经济要求。因此,基于非方系统的相对能量增益阵列,对胖系统进行变量配对分析,提出一种胖系统分程控制系统结构设计方法。该方法兼顾经济与控制性能,实现一个被控变量和分别侧重经济性能与控制性能的两个操纵变量的配对。通过实例分析说明,胖系统的分程控制系统结构设计方法不仅能够得到合理的变量配对,满足控制性能要求,而且能够保持经济性能尽可能优化。

The process industry’s requirements for cost reducing and profit boosting rise continuously,including the hope for reducing the operating cost as far as possible when controlled variables are adjusted by manipulated variables.Regarding a non-square fat system,the dimension of manipulated variables is more than that of the controlled variables,so the manipulated variables with low influence on economic performance are hoped to be put into control when there are small errors on controlled variables.Only when there are large errors on controlled variables and control requirements can’t be meet,the manipulated variables with high influence on economic performance and fast response will be put into control.In this regard,the traditional single-loop control system can’t meet economic requirements of the process control.In this paper,the relative energy gain array of non-square system was used to implement interaction analysis,and a split-range control configuration design method was introduced for the fat multivariable system.This method considers both economic performance and control performance,and it realizes the pairing of one controlled variable to two manipulated variables which focusing on economic performance and control performance respectively.Finally,a case study illustrated that,the split-range control configuration design for fat multivariable system can get a reasonable variable pairing and meet the control performance requirement,as well as optimize the economic performance as much as possible.