摘要:

AbstractThe freedom for eigenvalue assignment in specified areas of the complex plane and of the scope for placing the corresponding eigenvectors is utilized to form an analytical gradient‐based optimization problem which may be used to determine alow‐sensitivityeigenvalue assignment with astructurally constrainedandlow‐normlinear gain matrix. Examples are used to compare the properties of such optimized controllers with those obtained using single‐objective design tec

ISSN:0143-2087    

DOI:10.1002/oca.4660120302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractIn this paper we consider a general class of optimal control problems involving integrodifferential equations. The integral equation component is a Volterra integral equation with convolution kernel. A method is proposed to approximate the kernel which gives rise to a system of ordinary differential equations approximating the Volterra integral equation. Thus the optimal control problem is approximated by a sequence of standard optimal control problems involving only differential equations. Each of the approximate problems is solvable by any of the existing methods for standard optimal control problems, such as the gradient restoration algorithm and the control parametrization algorithm. Convergence analysis is also carried out to justify the proposed approximation. As an application we consider an optimal control problem involving production and marketing systems with distributed time lags. This problem is then solved numerically using the proposed method.

ISSN:0143-2087    

DOI:10.1002/oca.4660120303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThe problem of deriving a suboptimal LQG controller which is internally stable is considered. In the case where the controller is internally unstable a procedure is given for modifying the optimization parameters, i.e. the state weighting matrix and/or the process noise intensity. Sufficient conditions for controller stability of appropriately modified optimization problems are given for both the full‐order and reduced‐order cases. A final tuning procedure is then used to minimize the deviation from the original LQG prob

ISSN:0143-2087    

DOI:10.1002/oca.4660120304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThe design of controllers for active suspension systems can be formulated as an optimal control problem. The main objective of the controller is to isolate parts of the system from vibrations in other parts. Additional constraints are limited suspension travel, limited actuator force and good track‐holding capability. The objective and the constraints can be used in the formulation of an optimality criterion.Two criteria are examined, with the corresponding LQ andH∞control design methods. The methods are compared with respect to their ability to generate a controller that achieves the best performance. For the LQ method three controllers with different structures were generated.To illustrate the use of the design methods, controllers have been designed for a simple but typical suspension system. For this system the controllers based on a quadratic norm perform comparably but the controllers based on output feedback are less robust. TheH∞controller did not perform well for this problem when the same weighting functions were used to generate the controller as for the LQ method. Use of theH∞design method therefore requires careful tuning of the weighting functions. Use of the standard functions is inappr

ISSN:0143-2087    

DOI:10.1002/oca.4660120305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThis paper describes the modelling and learning control of a packed absorption column. The packed column is the most popular equipment used for process absorption. The absorption column is used to reduce the concentration of CO2in a gas mixture to a desired value. A solution of diethanolamine (DEA) is used as the absorbent. The flow rate of the absorbent and the concentration of CO2in the gas mixture are considered as control and controlled variables respectively. The process model has been developed from considerations of mass balances, transport phenomena and the chemical reaction in the liquid phase.A learning controller using a hierarchical structure of automata is used to achieve control of the column. The learning system is connected in a feedback manner with the column, which plays the role of the random medium where the learning system operates. Several simulation studies highlight the applicability of the learning control algorithm involved.

ISSN:0143-2087    

DOI:10.1002/oca.4660120306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThis paper presents a modified optimal load‐frequency controller for interconnected hydrothermal power systems. The weighting matrix of the optimal controller is sequentially modified to let the dominant energy open‐loop poles or poles in a conventional optimal feedback system be located in the desired region. The poles selected to be shifted are determined using the concept of dominant energy modes rather than those located closer to the imaginary axis. Improper pole placement can be avoided and very good system frequency and tie‐line power dynamic responses can be achieved by the proposed contr

ISSN:0143-2087    

DOI:10.1002/oca.4660120307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

ISSN:0143-2087    

DOI:10.1002/oca.4660120301

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY