Authors: None

Abstract:

Keywords:

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.90001

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: ---

Authors: None

Abstract:

Keywords:

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.90002

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: ---

Authors: None

Abstract:

Keywords:

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.90003

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: ---

Authors: Swierniak, Andrzej; Ploskonski, Pawel

Abstract: This paper is devoted to a problem of periodic scheduling of dosages of drugs in cancer treatment including modern anticancer modalities. Following considerations are focused on antiangiogenic therapy and combined antiangiogenic and chemotherapy. Combinations of antiangiogenic agents together with other types of therapies, such as chemotherapy, have shown promising results and became one of the most inspiring possibilities for cancer cure accomplishment. Conditions for asymptotic tumour eradication by periodic therapy protocols are shown from mathematical models describing the dynamics of both carcinogenesis and angiogenesis. Results of more realistic periodic control protocols are demonstrated using simulations.

Keywords:

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00004

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 1-6

Authors: Jikuya, Ichiro; Hodaka, Ichijo

Abstract: In the Floquet representation theorem, a state transition matrix whose second argument is 0 is represented as a product of a real-valued periodic matrix function and a real-valued matrix exponential function. In contrast, we have proposed a novel representation as a product of a real-valued periodic matrix function and two real-valued matrix exponential functions. In this note, the structure of the previously proposed representation is intensively investigated in terms of the maximum parametrization.

Keywords: periodic structures,periodic systems,linear systems,time-varying systems,fundamental matrices,transition matrices,Floquet theorem,Floquet theory,Lyapunov-Floquet transformation,parametrization

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00005

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 7-11

Authors: Böhm, Christoph; Allgöwer, Frank

Abstract: We propose an offline model predictive control approach for nonlinear periodically time-varying systems subject to state and input constraints. Under the assumption that the nonlinear system can be approximated using a periodic linear differential inclusion, we offline calculate a set of ellipsoids and associated feedback matrices by the solution of a semi-definite program. Online, the smallest ellipsoid containing the current state is determined, and the corresponding control law is applied to the system. The approach relaxes the conditions of existing approaches applicable to the considered system class. The effectiveness of the proposed controller is demonstrated by its application to a magnetic satellite attitude control problem.

Keywords: predictive control,periodic systems,linear matrix inequalities,satellite control

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00006

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 12-17

Authors: Kipscholl, Christian; Konigorski, Ulrich

Abstract: The design and application of cyclic control, which embraces Iterative Learning and Repetitive Control, for linear MIMO systems is presented in an algebraic framework. The algebraic framework is often used for the design of Iterative Learning Control and is also well suited for Repetitive Control. The algebraic framework allows an illustrative analysis and direct pole placement design of CC for SISO systems by diagonalization of the system matrix. MIMO systems can also be handled in this framework. However, a straight forward application of SISO designs for MIMO systems is not suggested. This approach will generally not yield a decoupling of control variables. This paper presents a decoupling cyclic MIMO control design. The design and implementation is conducted on a coupled biaxial material testing machine.

Keywords: MIMO,iterative learning control,repetitive control,pole placement,decoupling

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00007

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 18-23

Authors: Bragin, V. O.; Kuznetsov, N. V.; Leonov, G. A.

Abstract: The method of harmonic linearization, numerical methods, and the applied bifurcation theory together discover new opportunities for analysis of oscillations of control systems. In the present paper new algorithm for construction of counterexamples to Aizerman's conjecture and Kalman's conjecture is suggested.

Keywords: harmonic balance,harmonic linearization,describing function method,absolute stability,Aizerman problem,Kalman problem,periodic solution,hidden oscillation,localization

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00008

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 24-28

Authors: Kuznetsov, N. V.; Leonov, G. A.; Vagaitsev, V. I.

Abstract: The method of harmonic linearization, numerical methods, and the applied bifurcation theory together discover new opportunities for analysis of periodic oscillations of control systems. In the present paper these opportunities are demonstrated. New analytical-numerical method based on the above-mentioned technique is discussed. Application of this technique for attractor localization of generalized Chua's systems is given.

Keywords: chaotic attractor,Chua's system,Chua's circuits,hidden oscillations,hidden attractor localization,harmonic balance,harmonic linearization,describing function method

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00009

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 29-33

Authors: Kuznetsov, N. V.; Leonov, G. A.; Neittaanmäki, P.; Seledzhi, S. M.; Yuldashev, M. V.; Yuldashev, R. V.

Abstract: New method for the rigorous mathematical nonlinear analysis of PLL systems is suggested. This method allows to calculate the characteristics of phase detectors and carry out a rigorous mathematical analysis of transient process and stability of the system.

Keywords: phase-locked loops,nonlinear analysis,phase detector characteristic,misphasing,clock skew elimination,justification of linearization

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00010

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 34-38

Authors: Kuznetsova, O. A.; Leonov, G. A.

Abstract: The present work is devoted to the qualitative methods of study of periodic solutions of Lienard equation. This equation is often used in automatic control theory to describe the behavior of controllable generators (Cesari (1959); Lefschetz (1957)), where important tasks are to study the excitation of oscillations and analysis of limit cycles (Andronov et al. (1966); Bautin (1949)). Here, one of the most effective investigation methods is a method of computation and analysis of Lyapunov quantities (Poincare (1885); Lyapunov (1892)). In the present work the methods of computation of Lyapunov quantities and localization of limit cycles are demonstrated. These methods are applied to investigation of Lienard equation with small and large limit cycles. The expressions for the first four Lyapunov quantities for general Lienard system are obtained. By the transformation of quadratic system to a special type of Lienard equation and the method of asymptotical integration, quadratic systems with large limit cycles are investigated. The domain of parameters of quadratic systems, for which four limit cycles can be obtained, is determined.

Keywords: Lienard equation,oscillations,Hilbert's 16-th problem,small and large limit cycles,Lyapunov quantities,symbolic computation,localization of limit cycles

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00011

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 39-44

Authors: Pogromsky, A.; Matveev, A.

Abstract: The paper deals with the problem of estimation of the topological entropy for nonautonomous systems of differential equations via the second (direct) Lyapunov method. The main result of the paper is illustrated by examples concerning the Lorenz system and Duffing oscillator.

Keywords: entropy,nonlinear systems,time-varying systems,Lyapunov function

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00012

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 45-50

Authors: De Souza, Carlos E.; Coutinho, Daniel F.

Abstract: This paper deals with the problem of asymptotic stability of linear discrete-time periodic systems with a delayed state. A stability criterion independent of the time-delay length as well as a delay-dependent criterion are proposed, where the former applies to the case of a constant time-delay and the latter allows for a time-varying delay lying in a given interval. The developed stability criteria builds on Lyapunov-Krasovskii functionals and are given in terms of linear matrix inequalities. Extensions of the stability results for periodic systems with polytopic-type parameter uncertainty in the state-space matrices are also derived using parameter-dependent Lyapunov-Krasovskii functionals.

Keywords: asymptotic stability,robust stability,linear periodic systems,time-delay,discrete-time systems,Lyapunov-Krasovskii functional

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00013

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 51-56

Authors: Böhm, Christoph; Lazar, Mircea; Allgöwer, Frank

Abstract: This paper proposes a novel approach to stability analysis of discrete-time nonlinear periodically time-varying systems. The contributions are as follows. Firstly, a relaxation of standard Lyapunov conditions is derived. This leads to a less conservative Lyapunov function that is required to decrease at every period rather than at each time instant. Secondly, for linear periodic systems with constraints, we show that compared to standard Lyapunov theory, the novel stability concept yields a larger estimate of the region of attraction. An example illustrates the effectiveness of the developed theory.

Keywords: periodic systems,stability,region of attraction

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00014

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 57-62

Authors: Chauvin, Jonathan

Abstract: In this paper, we design exponentially convergent observers for a class of parabolic partial differential equations (PDEs) driven by an unknown periodic Neumann input with only boundary sensing available. The problem is posed as a problem of designing an invertible coordinate transformation of the observer error system into an exponentially stable system. Observer gains (output injection function) are shown to satisfy a well-posed hyperbolic PDE. Moreover, the observer gains are obtained in closed form. Simulation results are presented.

Keywords: partial differential equations,periodic motion,observers,input estimation

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00015

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 63-68

Authors: Chauvin, Jonathan; Petit, Nicolas

Abstract: Linear time-varying systems driven by periodic input signals are ubiquitous in control systems. For various reasons, including disturbance rejection and diagnosis by analysis of the trajectories, estimation of their input signals is often desirable. In the present paper, we illustrate a recently proposed general method to solve such problems by an asymptotic reconstruction of the Fourier expansion of the unknown input signal along with several examples from the automotive engine industry, and with an oscillating water column retrieving wave energy.

Keywords: observers,linear time-varying systems,periodic input signals,automotive applications,wave energy

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00016

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 69-74

Authors: Yamashita, Yuh

Abstract: The most important topic in chaos control is the stabilization of unstable periodic orbits (UPOs). The original delayed feedback control (DFC) method has an inherent weak point, called the odd number limitation. In this paper, we introduce a design method involving the use of nonlinear time-delayed observers, which can overcome the odd number limitation, in continuous-time chaotic systems. The proposed method is a natural extension of the discrete-time observer-based DFC method, which is insusceptible to the odd number limitation.

Keywords: chaos,observers,Floquet's theorem,delayed feedback control method

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00017

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 75-80

Authors: Borisenok, Sergei; Fradkov, Alexander; Proskurnikov, Anton

Abstract: A closed-loop (feedback) based algorithm calculating the classical external field for efficient control of qubit state is proposed. The approach is illustrated with two-level atomic system (with decay) driven by classical optical field. It is shown analytically and by simulation that the proposed method allows one to achieve the desired state expressed as the difference of the density matrix diagonal elements.

Keywords:

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00018

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 81-86

Authors: Hietarinta, Lassi; Toivonen, H. T.

Abstract: Least-squares support vector regression is applied to identify linear periodically time-varying (LPTV) systems. In this contribution the LPTV systems are modelled using a Fourier series representation of the transfer function and orthonormal filter expansions, such as Laguerre or Kautz filters. The model parameters are determined using least-squares support vector regression. In order to decrease complexity of the identified model, smoothness priors which penalize fluctuations of the frequency response can be introduced in the support vector procedure. The performance of the identified models are assessed by means of several simulation trials.

Keywords: Fourier series,identification,Kautz filter,Laguerre filter,least-squares method,orthonormal function expansion,periodic systems,support vector regression

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00019

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 86-91

Authors: Hyvämäki, Tapani; Zenger, Kai; Vesaoja, Eero

Abstract: Active vibration control in AC machines is used for minimizing the radial rotor vibrations. These vibrations are caused by structural characteristics of the machine and they occur in all kinds of electrical machines. Several active control methods have been applied in the machines and the results have been promising. This paper introduces two new methods that utilize the theory of linear time periodic systems. The first method gives a periodic feedback control as a solution to a discrete-time periodic Riccati equation (DPRE). The second method yields a feedforward type controller that is capable of compensating several simultaneous disturbance signals of different frequencies summed to the output of the system. It is possible to use these two control methods such that they form a serial control topology algorithm.

Keywords: AC machines,active control,disturbance compensation,periodic feedback control,LMS algorithm

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00020

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 92-97

Authors: Arkkio, A.; Zenger, K.

Abstract: The origins of the time-periodic torques and forces acting on the rotor of an electrical machine are searched for. The main task of an electrical machine operated in a steady state is to produce a constant torque. In an ideal case, this would be the only magnetic force on the rotor. In practice, the electromagnetic torque usually has relatively large ripple and significant lateral forces may also occur. The examples discussed are from radial flux machines, especially, from cage induction motors. As the electromagnetic torque and forces can be calculated from the air-gap magnetic field, the air-gap flux density and its harmonics are under special examination. Understanding the magnetic interactions may provide means to actively control the air-gap flux density and eliminate the parasitic effects.

Keywords: electrical machines,time-periodic,magnetic field,forces,torque,finite element analysis

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00021

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 98-103

Authors: Orivuori, J.; Zazas, I.; Daley, S.

Abstract: In this paper a method for suppressing frequency varying tonal disturbances is presented. In most of such processes additional components are required to be installed within the process to measure the disturbance frequency. The proposed nonlinear optimal controller is combined with an RLS-based frequency tracking algorithm. The resulting controller is adaptive in terms of the disturbance frequency and can act as a stand-alone solution for the suppression of tonal disturbances, requiring only measurements from the process output. The performance of the resulting controller is validated by implementation on a process emulating the problem of isolating vibration using flexible raft structures.

Keywords: active control,adaptive control,frequency tracking,vibration isolation,optimal control

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00022

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 104-109

Authors: Laiho, A.; Tammi, K.; Vidqvist, V.

Abstract: In this paper, linear time-periodic system dynamics in rotor vibration of electrical machines is examined. We consider a two-pole cage induction machine equipped with a built-in force actuator for active generation of lateral force on the rotor. The main contribution of the work is to identify and model the sources of time-periodic system dynamics in the coupled electromechanical actuator-rotor system. Especially, the effect of higher spatial harmonics of the magnetic field on the generated force is considered. In this work, a linear time-periodic model for the actuator-rotor system is derived. The parameters of the analytical model are estimated by using time-stepping finite-element analysis of the machine.

Keywords: linear time-periodic systems,active force actuation,induction machine,self-bearing machine,structural mechanics,finite element method,system identification

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00023

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 110-115

Authors: Hosoe, Yohei; Hagiwara, Tomomichi

Abstract: This paper is concerned with the discrete-time noncausal linear periodically time-varying (LPTV) scaling technique. It is defined through the discrete-time lifting, and it has been shown that even static noncausal LPTV scaling induces some frequency-dependent scaling when it is interpreted in the context of lifting-free treatment. It has been also shown that this feature together with the fact that the uncertainties come to be dealt with in their lifted forms leads to an effective method for robust stability analysis. This paper shows that noncausal LPTV scaling is effective also in controller design. More precisely, we study the periodic robust performance controller synthesis problem, and discuss how the properties of noncausal LPTV scaling lead to the performance improvement when the period of the controller is increased.

Keywords: discrete-time lifting,robust performance,periodic controllers,static separators

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00024

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 116-121

Authors: Dudarenko, Natalia; Ushakov, Anatoly

Abstract: Performance evaluation of multiple-input multiple-output (MIMO) systems needs to be a priori estimated. An algorithm of performance evaluation of MIMO discrete dynamic systems with periodic disturbances is proposed in the paper. It is based on degeneration factors that are constructed with singular values of criterion matrices of a MIMO system. The criterion matrices are created with the Sylvester matrix equation. The results are supported with an example.

Keywords: MIMO discrete system,periodic disturbance,degeneration factors,singular values,criterion matrix

Digital Object Identifier (DOI): 10.3182/20100826-3-TR-4016.00025

Conference: 4th IFAC International Workshop on Periodic Control Systems (2010)

Location: Bogazici University, Turkey

Start Date: Thu Aug 26 2010 - End Date: Sat Aug 28 2010

Page Numbers: 122-127