scholarly journals Iterative Data-Driven Control for Closed Loop with Two Unknown Controllers

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Hong Jianwang ◽  
Ricardo A. Ramirez-Mendoza ◽  
Ruben Morales-Menendez
Keyword(s):  
Stability Analysis ◽  
Unknown Parameter ◽  
Closed Loop ◽  
Transfer Functions ◽  
Controller Design ◽  
Classical Model ◽  
Data Driven ◽  
Model Matching ◽  
Matching Problem ◽  
Sensitivity Functions

Iterative idea is combined with data-driven control and is used to design the feedforward controller and feedback controller simultaneously. Consider one closed loop system with two controllers, the classical model-based control holds on the condition of known plant. To alleviate the modeling process for plant, data-driven control is applied to design the two controllers. After these two controllers are parametrized by two unknown parameter vectors, the iterative idea is introduced to identify these two parameter vectors. Furthermore, for more general case of controllers, the closed relations between controllers and expected transfer functions are derived. Then, the iterative idea is also introduced to achieve the controller design. To be of benefit for latter stability analysis, some equities are derived for output-input sensitivity functions with three kinds of disturbances. Generally, after formulating the problem of the controller design as one model-matching problem, the purpose of this paper is threefold. First, we derive that, in case of two parametrized controllers, the iterative idea is performed to identify these two unknown parameter vectors, even when parameters converge to their true values. Second, we show how to design the two controllers iteratively for more general forms and find the closed relations between these controllers and expected closed loop transfer functions. Third, we provide some heuristic considerations on output-input sensitivity functions, which are of benefit for our stability analysis on data-driven control. Finally, one example is given to show the feasibility of our proposed theories.

scholarly journals The discrete-time tracking problem with H∞ model matching approach plus integral control

2019 ◽  
Vol 292 ◽  
pp. 01018
Author(s):  
Murat Akın ◽  
Tankut Acarman
Keyword(s):  
Discrete Time ◽  
Closed Loop ◽  
Controller Design ◽  
Model Matching ◽  
Matching Problem ◽  
Design Algorithm ◽  
Integral Control ◽  
Loop Transfer Function ◽  
Model Transfer ◽  
Static Output

In this study, the discrete-time H∞ model matching problem with integral control by using 2 DOF static output feedback is presented. First, the motivation and the problem is stated. After presenting the notation, the two lemmas toward the discrete-time H∞ model matching problem with integral control are proven. The controller synthesis theorem and the controller design algorithm is elaborated in order to minimize the H∞ norm of the closed-loop transfer function and to maximize the closed-loop performance by introducing the model transfer matrix. In following, the discrete-time H∞ MMP via LMI approach is derived as the main result. The controller construction procedure is implemented by using a well-known toolbox to improve the usability of the presented results. Finally, some conclusions are given.

Application of Mixed H2/H∞ Data Driven Control Design to Dual Stage Hard Disk Drives

2018 ◽  
Author(s):  
Omid Bagherieh ◽  
Prateek Shah ◽  
Roberto Horowitz
Keyword(s):  
Closed Loop ◽  
Transfer Functions ◽  
Hard Disk Drives ◽  
Control Design ◽  
Hard Disk ◽  
Data Driven ◽  
Disk Drives ◽  
Design Strategies ◽  
Data Driven Approach ◽  
Dual Stage

A data driven control design approach in the frequency domain is used to design track following feedback controllers for dual-stage hard disk drives using multiple data measurements. The advantage of the data driven approach over model based approach is that, in the former approach the controllers are directly designed from frequency responses of the plant, hence avoiding any model mismatch. The feedback controller is considered to have a Sensitivity Decoupling Structure. The data driven approach utilizes H∞ and H2 norms as the control objectives. The H∞ norm is used to shape the closed loop transfer functions and ensure closed loop stability. The H2 norm is used to constrain and/or minimize the variance of the relevant signals in time domain. The control objectives are posed as a locally convex optimization problem. Two design strategies for the dual-stage hard disk drive are presented.

scholarly journals Stability Driven Optimal Controller Design for High Quality Images

Electronics ◽  
2018 ◽  
Vol 7 (12) ◽  
pp. 437 ◽  
Author(s):  
Sangmin Suh
Keyword(s):  
Optimal Design ◽  
Closed Loop ◽  
Controller Design ◽  
Design Method ◽  
Recognition Rate ◽  
Robot Vision ◽  
Sensitivity Functions ◽  
Closed Loop Systems ◽  
Conventional Methods ◽  
Performance Limitations

This note presents an optimal design method to enhance image quality in optical image stabilization (OIS) systems. First of all, performance limitations of conventional methods are shown and secondly, a new design framework based on convex optimization is proposed. The resulting controller essentially stabilizes the closed loop systems because the proposed method is derived from Lyapunov stability. From the test results, it is confirmed that this method reduces the effect of hand vibrations and makes images sharp. Additionally, it is shown that the proposed method is also effective in robot vision and recognition rate of deep neural network (DNN) based traffic signs and pedestrians detection in automotive applications. This note has three main contributions. First, performance limitations of the conventional method are shown. Second, from the relation between sensitivity and complementary sensitivity functions, an indirect design method for performance improvement is proposed, and finally, stability guaranteed optimal design is proposed. Unlike conventional methods, the proposed method does not require addition filters to suppress resonances of the plant and this note highlights phases of the closed loop systems on removing external vibrations.

Energy- and flatness-based control of DC-DC converters with nonlinear load

2018 ◽  
Author(s):  
Juan Tomassini ◽  
Alejandro Donaire ◽  
Sergio Junco
Keyword(s):  
Closed Loop ◽  
Controller Design ◽  
Digital Simulation ◽  
Model Matching ◽  
Power Electronic Converters ◽  
Nonlinear Load ◽  
Change Of Variables ◽  
Dc Power ◽  
Loop Dynamics ◽  
Matching Equation

"This paper presents a passivity-based controller design (PBC) aimed at stabilizing DC-DC power electronic converters with nonlinear dissipative loads. The converters considered in this work are the buck, the boost and the buck-boost. First, Bond Graph technique is used to obtain the flat output of each converter model. The controller is designed within the port-Hamiltonian (pH) framework, ensuring stability and other desired closed-loop properties. To this aim a desired closedloop dynamics in pH form with a quadratic storage function and a flat-output-inspired change of variables are proposed, which are common to the three converters. The controllers that render the closed-loop dynamics in the desired pH form are obtained via model matching. This design has two major advantages. The first is that the so-called matching equation can be solved by construction; thus, the cumbersome task of solving partial differential equations is avoided. The second advantage is that in all the converters treated the closed-loop dynamics is linear; thus, the performance of the control system can be easily determined via the tuning of the eigenvalues of the closed-loop evolution matrix. The performance is assessed through digital simulation."

Fixed-order data-driven H∞ controller synthesis for flexible mechanical systems: Two-stage approach

2020 ◽  
pp. 014233122094093
Author(s):  
Ayhan Arda Araz ◽  
S. Çağlar Başlamışlı ◽  
Uğur Mertcan Özmarangoz
Keyword(s):  
Controller Design ◽  
Classical Model ◽  
Mechanical Systems ◽  
Open Loop ◽  
Data Driven ◽  
Unknown Parameters ◽  
Nyquist Diagram ◽  
Two Stage ◽  
Model Based ◽  
Fixed Order

In this paper, a two-stage method is introduced to design fixed-order data-driven [Formula: see text] controller for flexible mechanical systems. In the first stage of the proposed method, unknown parameters of anti-resonance filter that is added to the forward path of the control loop of the system to minimize resonant peaks, are calculated using frequency domain data obtained from open-loop system identification tests. In the second stage, a fixed-order data-driven [Formula: see text] controller is calculated by solving an optimization problem under convex [Formula: see text] constraints obtained based on the Nyquist diagram. With the proposed method, lower order controllers that meets the performance constraints of classical model-based [Formula: see text] problems can be synthesized without need of a parametric plant model. The method developed in this study is tested experimentally on a military stabilized platform and its performance is compared with a model-based [Formula: see text] controller design method.

Algorithm for Approximate Model Matching for Loops With Non-Negligible Feedback Dynamics

1998 ◽  
Vol 120 (3) ◽  
pp. 394-398
Author(s):  
Luis Antonio Aguirre
Keyword(s):  
Closed Loop ◽  
Reference Model ◽  
Approximate Model ◽  
New Method ◽  
Moment Matching ◽  
Model Matching ◽  
Closed Loop System ◽  
Matching Problem ◽  
New Approach ◽  
Numerical Examples

This paper develops a new algorithm to solve the model matching problem in cases where the feedback dynamics should be taken into account in the design of the closed-loop system. One of the main features of the new method is that the matching is carried out by moment matching and is therefore approximate. The new algorithm is computationally simple and it permits the designer to choose relatively simple structures for the reference model and the controller. Numerical examples are included to illustrate the new approach.

scholarly journals Adaptive Data-Driven Control for Linear Time Varying Systems

Machines ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 167
Author(s):  
Talal Abdalla
Keyword(s):  
Design Problem ◽  
Controller Design ◽  
Reference Model ◽  
Linear Time ◽  
Convex Relaxation ◽  
Data Driven ◽  
Time Varying ◽  
Model Matching ◽  
Control Approach ◽  
Time Varying Systems

In this paper, we propose an adaptive data-driven control approach for linear time varying systems, affected by bounded measurement noise. The plant to be controlled is assumed to be unknown, and no information in regard to its time varying behaviour is exploited. First, using set-membership identification techniques, we formulate the controller design problem through a model-matching scheme, i.e., designing a controller such that the closed-loop behaviour matches that of a given reference model. The problem is then reformulated as to derive a controller that corresponds to the minimum variation bounding its parameters. Finally, a convex relaxation approach is proposed to solve the formulated controller design problem by means of linear programming. The effectiveness of the proposed scheme is demonstrated by means of two simulation examples.

scholarly journals A Robust Controller for Multivariable Model Matching System Utilizing a Quantitative Feedback Theory: Application to Magnetic Levitation

2019 ◽  
Vol 9 (9) ◽  
pp. 1753 ◽  
Author(s):  
Ramamurthy Jeyasenthil ◽  
Seung-Bok Choi
Keyword(s):  
Controller Design ◽  
Magnetic Levitation ◽  
Design Method ◽  
External Disturbance ◽  
Uncertain System ◽  
Disturbance Attenuation ◽  
Model Matching ◽  
Quantitative Feedback Theory ◽  
Matching Problem ◽  
And Control

This paper proposes a systematic feedback controller design methodology for multi-input multi-output (MIMO) uncertain systems using the quantitative feedback theory (QFT). To achieve this goal, the model matching problem was considered and the inversion feedforward controller was designed to improve control performance while reducing the demand on feedback control alone. The proposed method is formulated based on the concept of equivalent disturbance attenuation (EDA) approach in which the uncertain system problem is converted into an external disturbance rejection problem based on a nominal system. This proposed approach exhibiting non-sequential design method result in the suboptimal solution showing design simplicity and computational efficiency compared to the existing method. In order to validate the effectiveness of the proposed control methodology, the MIMO magnetic levitation system as adopted and control performances such as time response were presented in both time and frequency domains.

Sign in / Sign up

Export Citation Format

Share Document