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001			vtls000072576
003			KUKTEM
005			20251114204537.0
008			130621t2012 my a f m 000 0 eng d
020			_aTHE0006146(Local)
039		9	_a201905151603 _baida _c201710031609 _daishah _y201306211000 _zFida
040			_aUMP
090			_aTJ220 .T37 2012 rs Thesis
100	0		_aAt-Tasneem Binti Mohd Amin
245	1	0	_aA study on the applicability of symbolic computation in stabilising control design for switched systems / _cAt-Tasneem Binti Mohd Amin
260			_aBangi : _bUKM, _c2012
300			_ax, 138 p. : _bill. (some col.) ; _c30 cm. + _e1 CD-ROM
502			_aThesis (Master of Science) -- Faculty of Engineering And Built Environment - 2012
504			_aBibliography: p. 80-84
520	3		_aThis thesis examines the problem of designing controllers for switched systems that assures stability of the overall system. The switched systems here refer to systems whose dynamic behaviour changes from time to time. Stability concepts for continuous time and discrete event systems cannot be used to assure stability of switched systems as mode switching sequence and dwell time influences the stability of the overall system. One method of ensuring stability of switched systems is by proving the existence of a Common Lyapunov Function for the system. However, finding a Common Lyapunov Function is not trivial. Most methods that have been introduced to solve this problem involve the formulation of the system dynamic model and constraints into a Linear Matrix Inequality (LMI) structure. Then, computational methods are used to solve the LMI problem. Two problems arise from using LMIs to find solutions. Firstly, available LMI solvers use numerical computation which raises the possibility of rounding off errors. Secondly, the computational burden would be quite heavy, especially if the switched system comprises of a large number of subsystems or the subsystems are of a high order. The Haris-Rogers method is an alternative approach that has been previously developed for designing controllers based on the existence of a Common Lyapunov Function. In this approach, the problem is reduced to solving two sets of Linear Inequalities (LI), hence reducing the computational burden, as compared to methods that use LMIs. To overcome rounding off errors, symbolic computation methods should be used. However, this would require more computational power compared to numerical computation methods. In this study, a Switched System Control Design Toolbox employing symbolic computation based on the Haris-Rogers solution method was developed using the Maple software. A switched system with four second order subsystems was used as a test case and the toolbox successfully found a Common Lyapunov Function and subsequently designed the controller. For comparison, an LMI based method was tested with the same switched system using Maple and also three numerical LMI solvers, namely cvx, LMI Solver and Yalmip. Only Yalmip successfully generated a correct solution, while LMI Solver generated an incorrect solution since the controller obtained was clearly unstable. Maple and cvx failed to generate any controller. The Haris-Rogers method was also tested for the same switched system using cvx, LMI Solver and Yalmip, and all three produced correct results. All computational work and testing were performed on a system running Intel Core i5 2.67 GHz, 64-bit operating system with 2 GB RAM.
650		0	_aCluster analysis
650		0	_aCluster analysis _xData processing
856	4	0	_uhttp://ecollib.ump.edu.my/3786/ _zAccess in library only
999			_aVIRTUA40 _c3869 _d3875
999			_aVTLSSORT008002000400090010002450260030005020504052006500650185609992