Effect of linear transformation on nonlinear behavior of continuous prestressed beams with external FRP cables

Development of a Jacobian Module for Advanced Pulp and Paper Simulation and Control

TAPPI Journal ◽

10.32964/tj8.1.4 ◽

2009 ◽

Vol 8 (1) ◽

pp. 4-11

Author(s):

MOHAMED CHBEL ◽

LUC LAPERRIÈRE

Keyword(s):

Control System ◽

Nonlinear Behavior ◽

Simulation Software ◽

Pulp And Paper ◽

Pid Controllers ◽

Tuning Parameters ◽

Pid Tuning ◽

Fixed Set ◽

And Control ◽

Operating Points

Pulp and paper processes frequently present nonlinear behavior, which means that process dynam-ics change with the operating points. These nonlinearities can challenge process control. PID controllers are the most popular controllers because they are simple and robust. However, a fixed set of PID tuning parameters is gen-erally not sufficient to optimize control of the process. Problems related to nonlinearities such as sluggish or oscilla-tory response can arise in different operating regions. Gain scheduling is a potential solution. In processes with mul-tiple control objectives, the control strategy must further evaluate loop interactions to decide on the pairing of manipulated and controlled variables that minimize the effect of such interactions and hence, optimize controller’s performance and stability. Using the CADSIM Plus™ commercial simulation software, we developed a Jacobian sim-ulation module that enables automatic bumps on the manipulated variables to calculate process gains at different operating points. These gains can be used in controller tuning. The module also enables the control system designer to evaluate loop interactions in a multivariable control system by calculating the Relative Gain Array (RGA) matrix, of which the Jacobian is an essential part.

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REDUCED MODEL OF PLASMA DISCHARGE CONTROL IN TOKAMAK WITH IRON CORE

Computational nanotechnology ◽

10.33693/2313-223x-2020-7-3-11-22 ◽

2020 ◽

Vol 7 (3) ◽

pp. 11-22

Author(s):

VALERY ANDREEV ◽

◽

ALEXANDER POPOV

Keyword(s):

Optimal Control ◽

Inverse Problem ◽

Optimal Control Problem ◽

Control Problem ◽

Nonlinear Behavior ◽

Plasma Discharge ◽

Reduced Model ◽

Iron Core ◽

Power Sources ◽

Real Power

A reduced model has been developed to describe the time evolution of a discharge in an iron core tokamak, taking into account the nonlinear behavior of the ferromagnetic during the discharge. The calculation of the discharge scenario and program regime in the tokamak is formulated as an inverse problem - the optimal control problem. The methods for solving the problem are compared and the analysis of the correctness and stability of the control problem is carried out. A model of “quasi-optimal” control is proposed, which allows one to take into account real power sources. The discharge scenarios are calculated for the T-15 tokamak with an iron core.

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