A New Structured Multimodel Control of Nonlinear Systems by Integrating Stability Margin and Performance

2017 ◽  
Vol 139 (9) ◽  
Author(s):  
Mahdi Ahmadi ◽  
Mohammad Haeri
Keyword(s):  
Nonlinear Systems ◽  
Controller Design ◽  
A Priori ◽  
Design Procedure ◽  
Stability Margin ◽  
Point Tracking ◽  
Performance Requirements ◽  
Performance Specifications ◽  
And Performance ◽  
Model Redundancy

This paper deals with a new systematic multimodel controller design for nonlinear systems. The design of local controllers based on performance requirements is incorporated with the concept of local models selection as an optimization problem. Gap metric and stability margin are used as measuring tool and operation space dividing criterion, respectively. The developed method provides support to design a simple structured multiple proportional-integral (PI) controller which guarantees both robust stability and time-domain performance specifications. The main advantages of the proposed method are avoiding model redundancy, not needing a priori knowledge about system, having simple structure, and easing the implementation. To evaluate the presented multimodel controller design procedure, three benchmark nonlinear systems are studied. Both simulations and experimental results prove the effectiveness of the proposed method in set point tracking and disturbance rejection.

Multimodel Control of Nonlinear Systems: An Improved Gap Metric and Stability Margin-Based Method

2018 ◽  
Vol 140 (8) ◽  
Author(s):  
Mahdi Ahmadi ◽  
Mohammad Haeri
Keyword(s):  
Nonlinear Systems ◽  
Controller Design ◽  
A Priori ◽  
Stability Margin ◽  
Threshold Value ◽  
Performance Criteria ◽  
Local Models ◽  
Gap Metric ◽  
Maximum Stability ◽  
And Performance

This paper presents a new multimodel controller design approach incorporating stability and performance criteria. The gap metric is employed to measure the distance between local models. An efficient method based on state feedback strategy is introduced to improve the maximum stability margin of the local models. The proposed method avoids local model redundancy, simplifies the multimodel controller structure, and supports employing of many linear control techniques, while does not rely on a priori experience to choose the gridding threshold value. To evaluate the proposed method, three benchmark nonlinear systems are studied. Simulation results demonstrate that the method provides the closed-loop stability and performance via a simple multimodel structure in comparison with the opponents.

Barrel temperature control for quality of thermoplastic polymers in the extrusion process

2018 ◽  
Vol 2 (1) ◽  
Author(s):  
Murat Mayda
Keyword(s):  
Temperature Control ◽  
Control Strategy ◽  
Controller Design ◽  
Experimental Testing ◽  
Design Procedure ◽  
Extrusion Process ◽  
Operating Conditions ◽  
Single Screw Extruder ◽  
Performance Specifications

In this paper, the design procedure; modeling and controller design, testing are presented. Extensive tests have shown that the system reacts rapidly to changes in the operating conditions and effectively rejects disturbances due to unexpected changes in the quality of the material. This paper is the design and experimental testing of a feedback control system for the regulation of the volumetric flow in a polymer single screw extruder. Extruder temperature control is a challenging control problem. The problem becomes even more challenging when multiple barrel are included, such as in barrel temperature control for extruders. When characteristics of the system are examined, it becomes clear that a commonly used proportional plus compound plus derivative PID controller cannot meet such performance specifications for this kind of system. In order to achieve the required performance, a control strategy that utilizes techniques such as model predictive control, autotuning, and multiple parameter PID is formulated. This control strategy proves to be very effective in achieving the desired specifications.

Repetitive Controller Design in Parameter Space

2003 ◽  
Vol 125 (1) ◽  
pp. 134-138 ◽  
Author(s):  
Levent Gu¨venc¸
Keyword(s):  
Frequency Domain ◽  
Parameter Space ◽  
Controller Design ◽  
Design Method ◽  
Testing Machine ◽  
Design Procedure ◽  
Controller Parameter ◽  
Performance Specifications ◽  
Material Testing Machine ◽  
Repetitive Controller

A new and simple repetitive controller design procedure in controller parameter space, where the structure of the filters in the repetitive controller are fixed from the start and parameters within these filters are tuned, is presented here. This approach results in simple and physically meaningful controllers that are easily implementable. The design method is based on mapping frequency domain performance specifications into a chosen plane of controller parameters. Sensitivity function magnitude bounds and a relative stability measure are chosen as the frequency domain specifications to be mapped into controller parameter space here. The design method is illustrated numerically in the context of a servohydraulic material testing machine application available in the literature.

scholarly journals Global Asymptotic Stabilization Control for a Class of Nonlinear Systems with Dynamic Uncertainties

2015 ◽  
Vol 2015 ◽  
pp. 1-12
Author(s):  
Jiangbo Yu ◽  
Jizhong Wang ◽  
Zhongcai Zhang
Keyword(s):  
Nonlinear Systems ◽  
Controller Design ◽  
Initial Conditions ◽  
Design Procedure ◽  
Control Law ◽  
Asymptotic Stabilization ◽  
Control Approach ◽  
Global Asymptotic Stabilization ◽  
Stabilization Control ◽  
Dynamic Uncertainties

This paper is concerned with the global asymptotic stabilization control problem for a class of nonlinear systems with input-to-state stable (ISS) dynamic uncertainties and uncertain time-varying control coefficients. Unlike the existing works, the ISS dynamic uncertainty is characterized by the uncertain supply rates. By using the backstepping control approach, a systematic controller design procedure is developed. The designed control law can guarantee that the system states are asymptotically regulated to the origin from any initial conditions and the other signals are bounded in closed-loop systems. Moreover, it is shown that, under some additional conditions, a linear control law can be designed by the proposed methodology. The simulation example demonstrates its effectiveness.

scholarly journals Multi loop Controller Design for Multivariable Processes Employing SISO PI Tuning Rules

2019 ◽  
Vol 8 (6S4) ◽  
pp. 347-351
Keyword(s):  
Controller Design ◽  
Industrial Applications ◽  
Single Input Single Output ◽  
Distillation Columns ◽  
Proportional Integral ◽  
Point Tracking ◽  
Single Output ◽  
Internal Model Controller ◽  
And Performance ◽  
Tuning Rules

Ability of the proportional integral (PI) and proportional integral derivative (PID) controllers in set point tracking and disturbance rejection has led to their wide usage in industrial applications. The desired controller performance can be achieved by application of suitable tuning rules. The presence of interacting loops in a process makes it a challenging task of PI controllers design in multivariable processes. This problem highly mitigated by employing simple single input single output internal model controller (IMC). This IMC PI controller values are applied for different distillation process involving distillation columns like Wardle and Wood (WW) , Wood and Berry (WB) and Vinate-Luyben (V-L). The obtained simulation with proposed method gives better results and performance indices values compared to other control tuning strategies.

Sliding mode control revisited

2020 ◽  
Vol 42 (14) ◽  
pp. 2698-2707
Author(s):  
Masoud Bahraini ◽  
Mohammad Javad Yazdanpanah ◽  
Shokufeh Vakili ◽  
Mohammad Reza Jahed-Motlagh
Keyword(s):  
Nonlinear Systems ◽  
Controller Design ◽  
Sliding Mode ◽  
Design Procedure ◽  
Systematic Design ◽  
Closed Loop System ◽  
Guaranteed Stability ◽  
Sliding Mode Controllers ◽  
Bounded Disturbances ◽  
System States

Controller design for nonlinear systems in its general form is complicated and an open problem. Finding a solution to this problem becomes more complicated when unwanted terms, such as disturbance, are taken into account. To provide a robust design for a subclass of nonlinear systems, sliding mode controllers (SMCs) are used. These controllers have a systematic design procedure and can reject bounded disturbances and at the same time guarantee stability. The guaranteed stability is achieved by separating system states into two parts and assuming that the input to state stability (ISS) condition holds for internal dynamics. This condition restricts the applicability of the SMC and limits the system performance when the controller is designed based on that. In order to remove this restriction and improve the performance, the ISS condition has been relaxed in this study. The relaxation is performed by redesigning SMCs based on suggested Lyapunov functions. The proposed idea insures global asymptotic stability of the closed loop system and is used to revise different well-known SMCs such as conventional SMC, terminal SMC, non-singular terminal SMC, integral SMC, super-twisting SMC, and super-twisting integral SMC. Comparisons between conventional and revised versions are made using simulation to demonstrate excellence of the revisited controllers.

A multi-model control of nonlinear systems: A cascade decoupled design procedure based on stability and performance

2019 ◽  
Vol 42 (7) ◽  
pp. 1271-1280 ◽  
Author(s):  
Mahdi Ahmadi ◽  
Pouya Rikhtehgar ◽  
Mohammad Haeri
Keyword(s):  
Design Procedure ◽  
Performance Criteria ◽  
Gap Metric ◽  
Redundancy Problem ◽  
Model Control ◽  
Cascade Structure ◽  
Independent Cascade ◽  
And Performance ◽  
Model Redundancy ◽  
The Stability

Recently, the multi-model controllers design was proposed in the literature based on integrating of the stability and performance criteria. Although these methods overcome the redundancy problem, the decomposition step is very complex and time consuming. In this paper, a cascade design of multi-model control is presented that is made from two sequential steps. In the first step, the nonlinear system is decomposed into a set of linear subsystems by just considering the stability criterion. In this step, the gap metric is used as a smart tool to measure the distance between linear subsystems. While the closed-loop stability is gained through the first step, the performance is improved in the second step by adding internal model controllers in a cascade structure. Therefore, the proposed idea supports designing a multi-model controller in a simple way by integrating the stability and performance criteria in two independent cascade steps. As a result, the proposed method avoids the model redundancy problem, has a simple structure, guarantees the robust stability, and improves the performance. Two nonlinear chemical processes are simulated to evaluate the proposed multi-model controller approach.

Tracking Control of Robot Manipulator Using Sliding Mode Controller With Performance Robustness

1999 ◽  
Vol 121 (1) ◽  
pp. 64-70 ◽  
Author(s):  
Chieh-Li Chen ◽  
Rui-Lin Xu
Keyword(s):  
Tracking Control ◽  
Feedback Linearization ◽  
Controller Design ◽  
Sliding Mode ◽  
Robot Manipulator ◽  
Design Procedure ◽  
Sliding Mode Controller ◽  
Systematic Design ◽  
And Performance ◽  
The Stability

The tracking control problem of robot manipulator is considered in this paper. A sliding mode controller design with global invariance is proposed using the concept of extended system and feedback linearization. The sliding surface is assigned such that the sliding mode motion will occur while the proposed control law is applied. This results in a system with global invariance. The stability and performance of the resulting system can be guaranteed by the proposed systematic design procedure.

Robust Repetitive Controller Design in Parameter Space

2005 ◽  
Vol 128 (2) ◽  
pp. 406-413 ◽  
Author(s):  
Bilin Aksun Güvenç ◽  
Levent Güvenç
Keyword(s):  
Frequency Domain ◽  
Parameter Space ◽  
Controller Design ◽  
Design Method ◽  
Testing Machine ◽  
Design Procedure ◽  
Controller Parameter ◽  
Performance Specifications ◽  
Nominal Performance ◽  
Repetitive Controller

A new and simple robust repetitive controller design procedure in controller parameter space is presented here. The structure of the repetitive controller filters are fixed, thus, simplifying the design procedure to tuning of the fixed structure filters’ parameters. This approach results in simple and physically meaningful robust controllers that are easily implementable. The design method is based on mapping frequency domain performance specifications into a chosen controller parameter plane. Weighted sensitivity (nominal performance) and weighted complementary sensitivity (robust stability) function magnitude bounds are chosen as the frequency domain specifications to be mapped into controller parameter space here. The design method is illustrated numerically in the context of a servohydraulic material testing machine application available in the literature.

Barrel temperature control for quality of thermoplastic polymers in the extrusion process

2018 ◽  
Vol 1 (1) ◽  
Author(s):  
Murat Mayda
Keyword(s):  
Temperature Control ◽  
Control Strategy ◽  
Controller Design ◽  
Experimental Testing ◽  
Design Procedure ◽  
Extrusion Process ◽  
Operating Conditions ◽  
Single Screw Extruder ◽  
Performance Specifications

In this paper, the design procedure; modeling and controller design, testing are presented. Extensive tests have shown that the system reacts rapidly to changes in the operating conditions and effectively rejects disturbances due to unexpected changes in the quality of the material. This paper is the design and experimental testing of a feedback control system for the regulation of the volumetric flow in a polymer single screw extruder. Extruder temperature control is a challenging control problem. The problem becomes even more challenging when multiple barrel are included, such as in barrel temperature control for extruders. When characteristics of the system are examined, it becomes clear that a commonly used proportional plus compound plus derivative PID controller cannot meet such performance specifications for this kind of system. In order to achieve the required performance, a control strategy that utilizes techniques such as model predictive control, autotuning, and multiple parameter PID is formulated. This control strategy proves to be very effective in achieving the desired specifications.

Sign in / Sign up

Export Citation Format

Share Document