对于多输入多输出系统,在控制系统设计时首先要对被控变量和操纵变量进行控制结构选择.Bristol提出的相关增益矩阵(Relative gain array,RGA)法,以及学者们后来提出的各种改进方法,都只适用于稳定系统.本文针对不稳定系统,基于多变量广...对于多输入多输出系统,在控制系统设计时首先要对被控变量和操纵变量进行控制结构选择.Bristol提出的相关增益矩阵(Relative gain array,RGA)法,以及学者们后来提出的各种改进方法,都只适用于稳定系统.本文针对不稳定系统,基于多变量广义预测控制(Generalized predictive control,GPC)的闭环控制律提出了一种控制结构的变量匹配准则.通过对预测时域、控制时域等各个参数的优化选择,使系统闭环稳定;由闭环控制律得到被控变量期望值与操纵变量的相关性矩阵,以此得出控制结构的变量配对方案.通过实例研究表明,对于开环不稳定系统,该方法可以得出正确的变量配对结果.展开更多
Loop pairing is one of the major concerns when designing decentralized control systems for multivariable processes.Most existing pairing tools,such as the relative gain array(RGA) method,have shortcomings both in meas...Loop pairing is one of the major concerns when designing decentralized control systems for multivariable processes.Most existing pairing tools,such as the relative gain array(RGA) method,have shortcomings both in measuring interaction and in integrity issues.To evaluate the overall interaction among loops,we propose a statistics-based criterion via enumerating all possible combinations of loop statuses.Furthermore,we quantify the traditional concept of integrity to represent the extent of integrity of a decentralized control system.Thus,we propose that a pairing decision should be made by taking both factors into consideration.Two examples are provided to illustrate the effectiveness of the proposed criterion.展开更多
Nonlinear sliding m ode predictive controller is designed for a class of nonlinear system w ith unm odeled dynam ic characteristics and nonlinear term . The m ethod is based on nonlinear opti- m alpredictive control...Nonlinear sliding m ode predictive controller is designed for a class of nonlinear system w ith unm odeled dynam ic characteristics and nonlinear term . The m ethod is based on nonlinear opti- m alpredictive control. The variable structure controllaw m inim izes the quadratic index ofa predic- tive sliding m ode, w hich contains thecostfunction ofcontrolpreventing the controleffectfrom satu- ration for in m ostpracticalim plem entation the controlinputs are bounded by physicalconstraints and energy constraints. According to the im m easurable states, the variable structure observer for nonlin- ear system sisadapted. The variablestructure system m ethod isaptto therealization ofobserverw ith variable param eters and uncertainty. The proofshow s thatthe states ofthe observer asym ptotically convergence to the realstates ofthe system although itisofuncertainty and nonlinear term s. Final- ly, the digitalsim ulation results prove the effectiveness ofthe proposed m ethod.展开更多
文摘对于多输入多输出系统,在控制系统设计时首先要对被控变量和操纵变量进行控制结构选择.Bristol提出的相关增益矩阵(Relative gain array,RGA)法,以及学者们后来提出的各种改进方法,都只适用于稳定系统.本文针对不稳定系统,基于多变量广义预测控制(Generalized predictive control,GPC)的闭环控制律提出了一种控制结构的变量匹配准则.通过对预测时域、控制时域等各个参数的优化选择,使系统闭环稳定;由闭环控制律得到被控变量期望值与操纵变量的相关性矩阵,以此得出控制结构的变量配对方案.通过实例研究表明,对于开环不稳定系统,该方法可以得出正确的变量配对结果.
基金supported by the National High-Tech Research and Development Program (863) of China (No.2009AA04Z154)the National Natural Science Foundation of China (No.60736021)
文摘Loop pairing is one of the major concerns when designing decentralized control systems for multivariable processes.Most existing pairing tools,such as the relative gain array(RGA) method,have shortcomings both in measuring interaction and in integrity issues.To evaluate the overall interaction among loops,we propose a statistics-based criterion via enumerating all possible combinations of loop statuses.Furthermore,we quantify the traditional concept of integrity to represent the extent of integrity of a decentralized control system.Thus,we propose that a pairing decision should be made by taking both factors into consideration.Two examples are provided to illustrate the effectiveness of the proposed criterion.
文摘Nonlinear sliding m ode predictive controller is designed for a class of nonlinear system w ith unm odeled dynam ic characteristics and nonlinear term . The m ethod is based on nonlinear opti- m alpredictive control. The variable structure controllaw m inim izes the quadratic index ofa predic- tive sliding m ode, w hich contains thecostfunction ofcontrolpreventing the controleffectfrom satu- ration for in m ostpracticalim plem entation the controlinputs are bounded by physicalconstraints and energy constraints. According to the im m easurable states, the variable structure observer for nonlin- ear system sisadapted. The variablestructure system m ethod isaptto therealization ofobserverw ith variable param eters and uncertainty. The proofshow s thatthe states ofthe observer asym ptotically convergence to the realstates ofthe system although itisofuncertainty and nonlinear term s. Final- ly, the digitalsim ulation results prove the effectiveness ofthe proposed m ethod.
