Publications by Alireza Karimi

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Some frequency-domain controller design problems are solved using a finite number of frequency samples. Consequently, the performance and stability conditions are not guaranteed for the frequencies between the frequency samples. In this paper, all possible ...

Noniterative data-driven techniques are design methods that allow optimal feedback control laws to be derived from input-output (I/O) data only, without the need of a model of the process. A drawback of these methods is that, in their standard formulation, ...

A new model reference data-driven approach is presented for synthesizing controllers for the CERN power converter control system. This method uses the frequency re- sponse function (FRF) of a system in order to avoid the problem of unmodeled dynamics assoc ...

High performance output tracking can be achieved by precompensator or feedforward controllers based on the inverse of either the closed-loop system or the plant model, respectively. However, it has been shown that these inverse controllers can adversely af ...

Iterative Learning Control (ILC) is a technique used to improve the tracking performance of systems carrying out repetitive tasks, which are affected by deterministic disturbances. The achievable performance is greatly degraded, however, when non-repeating ...

In this paper an Iterative Learning Control (ILC) algorithm is proposed for a certain class of Linear Parameter Varying (LPV) systems whose dynamics change between iterations. Consistency of the algorithm in the presence of stochastic disturbances is shown ...

Increasing the scanning speed in Atomic Force Microscopy (AFM) relies on improving the tracking performance in the vertical direction of motion. The lightly damped resonances of piezo-actuators utilized in AFM nano-positioning stages hinder the maximum ach ...

A recent method for robust fixed-order H-infinty controller design by convex optimization proposed in [1] is investigated in this paper for the tuning of multivariable controllers. Linear Time-Invariant Multi-Input Multi-Output (LTI-MIMO) systems represent ...

Adaptive optics (AO) systems are used in ground- based telescopes to improve image resolutions, especially for long-exposure photography, by compensating for the effects of atmospheric turbulence and internal vibrations. Most current AO systems are based o ...

The inter-area oscillations are common in power system and can occur due to the changes in the load or generation power especially in long transmission lines. This paper presents the design of a robust fixed-order loop shaping controller to damp out the in ...

Robust control synthesis of linear time-invariant SISO polytopic systems is investigated using the polynomial approach. A convex set of all stabilizing controllers for a polytopic system is given over an infinite-dimensional space. A finite-dimensional app ...

All H infinity controllers of a SISO LTI system are parameterized thanks to the relation between the Bounded Real Lemma and the Positive Real Lemma. This new parameterization shares the features of Youla parameterization, namely the convexity of H infinity ...

This paper presents an approach for fixed-order Linear Parameter Varying (LPV) controller design with application to a 2 Degree-of-Freedom (2DOF) gyroscope experimental setup. Inner convex approximation of the non-convex set of all stabilizing fixed-order ...

This paper examines the identification of a single-output two-input system. Motivated by an experiment design problem(should one excite the two inputs simultaneously or separately), we examine the effect of the (second) input signal on the variance of the ...

In this paper, a new data-driven distributed control structure for frequency/voltage regulation and active/reactive power sharing of islanded microgrids is proposed. By using a droop-free concept, the proposed method avoids the inherent timescale separatio ...

The flexible transmission benchmark was proposed in the European Journal of Control to evaluate some robust digital control approaches in 1995. With progress in convex optimization algorithms new methods for robust controller design are developed. A recent ...

A new approach is presented in the paper for modelling uncertainty as an elliptical set for robust controller synthesis. The method involves finding the best linear nominal model and the corresponding elliptical uncertainty set that is consistent with a se ...

A new method for robust fixed-order H-infinity controller design for uncertain time-delay systems is presented. It is shown that the H-infinity robust performance condition can be represented by a set of convex constraints with respect to the parameters of ...

Understanding hierarchical self-assembly of biological structures requires real time measurement of the self-assembly process over a broad range of length- and timescales. The success of high-speed atomic force microscopy (HS-AFM) in imaging small scale mo ...

A dynamic phasor model for low- and medium-voltage distribution grids is presented. This model accurately represents the transient dynamics of this type of grid, and its low order makes it well suited for control design. A novel fixed-structure, robust con ...

Alireza Karimi

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Robust Controller Design by Convex Optimization based on Finite Frequency Samples of Spectral Models

Enhancing statistical performance of data-driven controller tuning via L2-regularization

A Data-Driven Approach to Power Converter Control via Convex Optimization

Model-Free Precompensator Tuning Based on the Correlation Approach

A Statistical Analysis of Certain Iterative Learning Control Algorithms

Linear Parameter Varying Iterative Learning Control

Data-driven control in atomic force microscopy using a genetic algorithm

H-infinity Controller Design for Spectral MIMO Models by Convex Optimization

Direct Data-Driven Vibration Control for Adaptive Optics

Design of a Fixed-Order Robust Controller Using Loop Shaping Method for Damping Inter-Area Oscillations in Power Systems

Robust Control of Polytopic Systems by Convex Optimization

An Alternative to the Youla Parameterization for H infinity Controller Design

Fixed-order Linear Parameter Varying Controller Design for a 2DOF Gyroscope

Identification of a Two-Input System: Variance Analysis

Data-driven distributed frequency/voltage and power sharing control for islanded microgrids

A solution to the flexible transmission benchmark by convex optimization

Data-driven IQC-Based Uncertainty Modelling for Robust Control Design

Robust Smith Predictor Design for Time-Delay Systems with H infinity Performance

Large‐Range HS‐AFM Imaging of DNA Self‐Assembly through In Situ Data‐Driven Control

Advanced Droop Control in Islanded Microgrids Using Dynamic Phasor Models