Optimal tuning of PID controllers for first order plus time delay models using dimensional analysis (original) (raw)

PID Tuning Rules for First Order plus Time Delay System

2014

This paper demonstrates an efficient method of tuning the PID controller parameters using different PID tuning techniques. The method implies an analytical calculating the gain of the controller (Kc), integral time (Ti) and the derivative time (Td) for PID controlled system whose process is modelled in first order plus time delay (FOPTD) form. In this Paper a First order time delay system is selected for study. The performance of PID tuning techniques is analysed and compared on basis of time response specifications.

Design of a Nonlinear PID Controller and Tuning Rules for First-Order Plus Time Delay Models

Studies in Informatics and Control, 2019

This paper introduces a simple but effective nonlinear proportional-integral-derivative (PID) controller and three model-based tuning rules for first-order plus time delay (FOPTD) models. The proposed controller is based on a conventional PID control architecture, wherein a nonlinear gain is coupled in series with the integral action to scale the error. The optimal parameter sets of the proposed PID controller for step setpoint tracking are obtained based on the FOPTD model, dimensional analysis and a genetic algorithm. As for gauging the performance of the controller, three performance indices (ISE, IAE and ITAE) are adopted. Then, tuning rules are derived using the tuned parameter sets, potential rule models and the least squares method. The simulation results carried out on three processes demonstrate that the proposed method exhibits better performance than the conventional linear PID controllers.

A Comparative Study of Pid Controller Tuning Techniques for Time Delay Processes

2019

The Proportional-Integral-Derivative (PID) controllers are used in process/plant for controlling their parameters such as thermal or, electrical conductivity. By adjusting three parameters of PID controller, both transient and steady response can be improved, and better output can be obtained. There are many PID controller tuning techniques available in the literature and designing PID controllers for small delay processes with specified gain and phase margin is a well-known design technique. If the gain margin and phase margin are not specified, the system may not be optimum. A system with large gain and phase margins is more robust and gives better performance. When the system is robust, there will be no effect of slight changes in system parameters on the system performance. This paper describes a comparative analysis, among different types of tuning techniques available for first order plus delay time systems (FOPDT) on the basis of the various time integral performance criteria...

Tuning PID Controllers for Time-Delay Processes with Maximizing the Degree of Stability

In this paper, we propose a method of tuning PID controller parameters for first-order plus dead-time processes with the objective of maximizing the degree of stability. Since the presence of dead-time in a feedback loop gives rise to an infinite-dimensional closed-loop system, which has an infinite number of poles and thus the conventional Routh-Hurwitz algebraic criterion of stability cannot be applied to characterize the necessary conditions of the maximum degree of stability. To overcome this difficulty, we make use the theory of D-partition technique. Based on analytically characterizing the D-partition boundaries of the controller parameter space, necessary conditions of the maximum degree of stability are derived. With these derived conditions, the problem of maximizing the degree of stability is converted to a set of parametric optimization problems, whose solutions can be obtained by an existing method. For showing the applicability of the method, a tuning example with graphical illustrations is given.

A simple method of tuning PID controller for Integrating First Order Plus time Delay Process

2016

A simple method is proposed to design a PID controller for Integrating First Order Plus Time Delay system. Design is simple compared to the other tuning methods. It has been proposed for the pneumatic control system based on the method of gain scheduling. The performance of the controller is measured by the simulation and it is compared with the other two tuning methods which is Skogested [1] and Shinskey [2]. Simulation results shows that the proposed method has lesser error ISE and IAE than the other two methods. Disturbance rejection is also good in the proposed method. INTRODUCTION PID controller design based on stability analysis, constant open loop transfer function, pole placement method, stable inverse of the model and direct synthesis method has been proposed. In all the above methods the design procedure is somewhat complicated. A simple method is proposed for First Order Plus Time Delay system by using the method of gain scheduling [3]. But PID controller for Integrating ...

Tuning of PID-type controllers for stable and unstable systems with time delay

1994

A graphical technique for tuning PID-type controllers based on the method of D-partition is proposed for single-input-single-output linear time invariant systems. The tuning method shifts all the roots of the characteristic equation of the controlled system to a certain desirable region in the left half of the complex plane (LHP) to achieve a specified least absolute and least relative stability margin. The method can be used to tune a precompensator, in a two degree of freedom structure, so as to improve tracking behaviour. The method can be used for both stable and unstable systems, for systems with significant time delay and for various controller configurations, including derivative in the feedback path.

Tuning of a PD-PI Controller used with First-order-Delayed Processes

International journal of engineering research and technology, 2014

Time delayed processes require more attention in selecting reasonable controllers associated with them because of the poor performance of the control system associated with them. In this work, the PD-PI controller is examined to investigate its replacement to the classical PID controller. This research work has proven that the PD-PI results in a better performance for the closed-loop control system incorporating the PD-PI controller and a first-order delayed process. A first-order-delayed process of 50 s time constant and time delay between 2 and 16 seconds is controlled using simulation. The time delay effect is compensated using 4 th order Pade approximation. The controller is tuned by minimizing the sum of square of error (ISE) of the control system using MATLAB. The MATLAB optimization toolbox is used assuming that the tuning problem is an unconstrained one. The result was reducing the maximum percentage overshoot, maximum percentage overshoot and settling time. The performance of the control system using an PD-PI controller using the present tuning technique is compared with that using a PID controller tuned by Ziegler-Nichols and Tavakoli tuning techniques.

Comparison of Pi Controller Performance for First Order Systems with Time Delay

2017

Delays appear often in all real world engineering systems. Delay systems have the property that the rate of variation in the system state depends on the previous states also. They are frequently a source of instability and poor system performance. In order to get the required performance from the delay system controller design plays a vital role. Because of the robust nature, easy structure Proportional Integral Derivative (PID) controllers are extensively used in many industrial loops. Parameter tuning of the PID controller is an essential task. Numerous industrial processes, whose transfer function is of first order, can be easily controlled with PI controllers. This paper presents the comparative analysis of an approach based on Lambert W function for PI controller design for first order systems with time delay among Smith predictor (SP) and ZeiglerNichols (ZN) methods of design. Performance of the considered methods in terms of various performance specifications through simulati...

PID control design for first-order delay systems via MID pole placement: Performance vs. robustness

Automatica, 2022

The PID control is favored in controlling industrial processes for its ease of implementation. In this paper we present an analytical study, with an aim at stability robustness, tracking performance, and pole placement of first-order unstable plants under PID control. We employ a multiplicity-induced dominancy (MID) strategy to design and tune PID controller gains, which is shown to possess desirable properties that ensure specified decay rate of the closed-loop response and the stability robustness of the closed-loop system in spite of variations in the delay parameter. We also study the tradeoff between delay robustness and tracking performance of PID controllers. We show that under the constraint of steady-state tracking, the maximal delay robustness range can be computed by solving a unimodal pseudo-concave optimization problem.