Modeling and control of plate type heat exchangers using PI and PID controllers

Classical modeling and control methods applied to differential locomotion mobile robots generate mathematical equations that approximate the dynamics of the system and work relatively well when the system is linear in a specific range. However, they may have low accuracy when there are many variations of the dynamics over time or disturbances occur. To solve this problem, we used a recursive least squares (RLS) method that uses a discrete-time structure first-order autoregressive model with exogenous variable (ARX). We design and modify PID adaptive self-adjusting controllers in phase margin and pole allocation. The main contribution of this methodology is that it allows the permanent and online update of the robot model and the parameters of the adaptive self-adjusting PID controllers. In addition, a Lyapunov stability analysis technique was implemented for path and trajectory tracking control, this makes the errors generated in the positioning and orientation of the robot when performing a given task tend asymptotically to zero. The performance of the PID adaptive self-adjusting controllers is measured through the implementation of the criteria of the integral of the error, which allows to determine the controller of best performance, being in this case, the PID adaptive self-adjusting type in pole assignment, allowing the mobile robot greater precision in tracking the trajectories and paths assigned, as well as less mechanical and energy wear, due to its smooth and precise movements.

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Fully Automated Tuning and Implementation of Fractional PID Controllers

Volume 4: 7th International Conference on Multibody Systems, Nonlinear Dynamics, and Control, Parts A, B and C ◽

10.1115/detc2009-87399 ◽

2009 ◽

Cited By ~ 1

Author(s):

Guillermo E. Santamaria ◽

Ine´s Tejado ◽

Blas M. Vinagre ◽

Concepcio´n A. Monje

Keyword(s):

Transfer Function ◽

Fractional Order ◽

A Priori ◽

Pid Controllers ◽

Relay Feedback ◽

Modeling And Control ◽

Tuning Method ◽

And Control ◽

Automated Tuning ◽

Tustin Operator

The advantages and applications of modeling and control of non-integer order linear systems are well known, but the inherent complexity of practical approximations has prevented the generalized appearance in the market of simple devices capable of implementing a fractional order control on a unknown given plant in a reliable way. The purpose of this work is to make a step forward in this sense, looking for a compromise between simplicity and reliability of the system. An automatic method for tuning, design, and implementation of fractional order PIαDμ controllers is presented in this paper. The auto-tuning method is based on plant magnitude and phase measuring at a frequency of interest, obtained by the relay feedback technique. A fractional order PIαDμ controller is designed from these measurements so that specifications of phase margin and robustness to variations of the plant gain are reached. Once the fractional order PIαDμ controller transfer function is obtained, it is discretized applying Pascal Matrix Method, and approximated using continuous fraction expansion of the Tustin Operator, generalized for a general transfer function. Simulation results obtained using the described method on an a priori unknown characteristic servo are presented in this paper.

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Dynamic Modeling of Heat Exchangers With Humidity and Condensation

Volume 3: Multiagent Network Systems; Natural Gas and Heat Exchangers; Path Planning and Motion Control; Powertrain Systems; Rehab Robotics; Robot Manipulators; Rollover Prevention (AVS); Sensors and Actuators; Time Delay Systems; Tracking Control Systems; Uncertain Systems and Robustness; Unmanned, Ground and Surface Robotics; Vehicle Dynamics Control; Vibration and Control of Smart Structures/Mech Systems; Vibration Issues in Mechanical Systems ◽

10.1115/dscc2015-9646 ◽

2015 ◽

Author(s):

Herschel Pangborn ◽

Andrew G. Alleyne

Keyword(s):

Heat Exchangers ◽

Cross Flow ◽

Control Design ◽

Vapor Compression ◽

Air Humidity ◽

Modeling And Control ◽

Air Inlet ◽

Condensate Formation ◽

Simulation Results ◽

And Control

The effects of air humidity on the performance of refrigerant-to-air heat exchangers in vapor compression systems (VCSs) are non-negligible in modeling and control design for some applications. Such applications include both those in which the ambient humidity is expected to vary greatly over time and those in which control of the air outlet humidity is desired. This paper presents a control-oriented dynamic model for cross-flow refrigerant-to-air heat exchangers that uses knowledge of the air inlet humidity to improve the accuracy of refrigerant-side and air-side outputs, as well as to calculate the air outlet humidity and rate of condensate formation. Simulation results are validated with experimental data collected from a 1kW VCS test stand.

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Modeling and Control of a Food Extrusion Process

Computers & Chemical Engineering ◽

10.1016/s0098-1354(97)00075-6 ◽

1997 ◽

Vol 21 (1-2) ◽

pp. S361-S366 ◽

Cited By ~ 1

Author(s):

J Elsey

Keyword(s):

Extrusion Process ◽

Modeling And Control ◽

Food Extrusion ◽

And Control

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Modeling and Control of a Chemical Waste Water Treatment Plant

Computers & Chemical Engineering ◽

10.1016/s0098-1354(97)00171-3 ◽

1997 ◽

Vol 21 (1-2) ◽

pp. S947-S952 ◽

Cited By ~ 2

Author(s):

R Miller

Keyword(s):

Waste Water ◽

Water Treatment ◽

Waste Water Treatment ◽

Treatment Plant ◽

Water Treatment Plant ◽

Waste Water Treatment Plant ◽

Chemical Waste ◽

Modeling And Control ◽

And Control

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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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