EPE Association: EPE-PEMC 2004 - Topic 07-7: Modelling and simulation

EPE-PEMC 2004 - Topic 07-7: Modelling and simulation
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2004 - Conference > EPE-PEMC 2004 - Topic 07: MOTION CONTROL, ROBOTICS AND ADJUSTABLE SPEED DRIVES > EPE-PEMC 2004 - Topic 07-7: Modelling and simulation

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   Advanced Control Techniques For Rolling Mills
By Aldo Balestrino, Alberto Landi, Luca Sani [View]
[Download]

Abstract: This paper addresses the problem of the product quality improvement in hot rolling mills. The simplest scheme for modeling the rolling process considers the reduction of a strip thickness by passing the hot strip through a preset roll gap between two work rolls. Each rolling stand is driven by a DC motor, which is equipped with a speed controller. Usually the two DC motors are separately controlled; i.e. each servo drive acts only on its motor, by imposing equal set points. An important condition to guarantee for a high product quality is the equalization of the motor torque acting on the two work rolls. Experimental data show that small differences between the angular speeds of the upper and of the lower work rolls lead to sensible differences between the two motor torques, deteriorating the product quality. A combined-control of the upper and lower DC servo-drives reduces the speed fluctuations; different control techniques, - including variable structure PI controllers - are proposed, evaluated and compared by extensive simulation tests.

   Analysis Of The Fluid Flow In The Channel Of A MHD Pump
By F. Z. Kadid, R. Abdessemed, S. Drid [View]
[Download]

Abstract: This paper deals with the study of an unsteady fluid flow in a MHD pump fed with sinusoidal current at variable frequency for the mercury pumping using an alternate coupling finite element and volume computation with an adaptation of the nodes. By introducing vector potentials ( ) ø , A and the vorticity î, a system of equations which are of the elliptic type for describing a velocity and pressure distribution in the channel is obtained. In this analysis, the width of the channel is taken into account and the results are compared to those obtained in the limit case when the width is much smaller or much bigger than a characteristic dimension of the channel. The results show the influence of the frequency on the fluid flow of the MHD pump.

   Development Of Real-Time Minimal Models For Belt Conveyor Systems
By Uwe Druessner [View]
[Download]

Abstract: Belt conveyors are effective means of transportation in industrial systems. With the presence of speed-controlled acdrives in belt conveyor systems it is very common to meet the problem of oscillations, which cause the abrasion in mechanical parts. The task is, to find out general, real-time-minimal-models for belt conveyors, which primarily should support to design process control structures for real plants faster and more efficient.

   Equivalent Circuit Model Of The Cycloconverter-Fed Synchronous Motor
By Lin Hua, Xingwei Wang, Yunping Zou [View]
[Download]

Abstract: This paper proposes a new analysis approach for analytic study of the cycloconverter-fed synchronous motor, based on the analysis of its operation characteristics. That is, the d- and q-axis variables of a synchronous motor are decomposed to low-frequency components (including aperiodic components) and high-frequency components, which can be treated separately. In this case, the resistances of rotor circuits to highfrequency components and the effect of damper winding on lowfrequency components are negligible. Therefore, by using this analysis approach, the equivalent circuit model of a synchronous motor is obtained for steady-state and quasisteady- state analysis. Furthermore, this model is used for designing current controller of the cycloconverter-fed synchronous motors drive system. The simulation results show the equivalent circuit model established in this paper is correct, which provides theoretical basis and methods for the analytical analysis of the cycloconverter-fed synchronous motor system.

   Mathematical Models Of 1h Electromechanical System For Investigations Of Transient States And Sensitivity
By Z. Glowacz, K. Jaracz [View]
[Download]

Abstract: In this paper the problem of mathematical description of complex electromechanical system with 1H thyristor converter is considered. This system has been described using algebraic, logical and stiff differential equations. Created mathematical model permits to investigate the transient phenomena. On the basis of mathematical model of system the associated sensitivity models have been constructed. Associated models permit to determine the behaviour of electromechanical system with 1H converter on variations of stochastic disturbance parameters in supply voltage and system parameters. Criteria of sensitivity of system on variations of parameters have been determined. In this paper are presented sensitivity functions of electromechanical system with 1H converter. Investigated electromechanical system belongs to discrete-continuous systems.

   Sensorless A. C. Drive With Vector Controlled Synchronous Motor
By Ondrej Fiser, Petr Palacky, Pavel Brandstetter [View]
[Download]

Abstract: In the paper a method for speed and position estimation for the permanent magnet synchronous motor (PMSM) were described. By using monitored stator voltage and currents and Kalman observers, it is possible to implement high - dynamic – performance PMSM drives without position and speed sensors. An Extended Kalman Filter (EKF) is a recursive optimum – state estimator which can be used for the joint state and parameter estimation of a non – linear dynamics system in real – time. The mathematical model of the vector controlled drive system in Matlab Simulink was used for simulation.

   Simulation Tools For Design And Testing Of Electric Drives
By A. V. Loparev, V. M. Vodovozov [View]
[Download]

Abstract: An electric drive belongs to inhomogeneous, nonlinear and non-stationary systems, and its optimal design is related to the class of multi-criteria problems of non-linear programming that has been divided by three groups of tasks. The new eDrive software has been developed that helps in maintenance some designing stages. The interactive recursive procedure is discussed that provides the selection and testing electric drives units.

EPE-PEMC 2004 - Topic 07-7: Modelling and simulation
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2004 - Conference > EPE-PEMC 2004 - Topic 07: MOTION CONTROL, ROBOTICS AND ADJUSTABLE SPEED DRIVES > EPE-PEMC 2004 - Topic 07-7: Modelling and simulation
	[return to parent folder]

	Advanced Control Techniques For Rolling Mills By Aldo Balestrino, Alberto Landi, Luca Sani	[View] [Download]
Abstract: This paper addresses the problem of the product quality improvement in hot rolling mills. The simplest scheme for modeling the rolling process considers the reduction of a strip thickness by passing the hot strip through a preset roll gap between two work rolls. Each rolling stand is driven by a DC motor, which is equipped with a speed controller. Usually the two DC motors are separately controlled; i.e. each servo drive acts only on its motor, by imposing equal set points. An important condition to guarantee for a high product quality is the equalization of the motor torque acting on the two work rolls. Experimental data show that small differences between the angular speeds of the upper and of the lower work rolls lead to sensible differences between the two motor torques, deteriorating the product quality. A combined-control of the upper and lower DC servo-drives reduces the speed fluctuations; different control techniques, - including variable structure PI controllers - are proposed, evaluated and compared by extensive simulation tests.

	Analysis Of The Fluid Flow In The Channel Of A MHD Pump By F. Z. Kadid, R. Abdessemed, S. Drid	[View] [Download]
Abstract: This paper deals with the study of an unsteady fluid flow in a MHD pump fed with sinusoidal current at variable frequency for the mercury pumping using an alternate coupling finite element and volume computation with an adaptation of the nodes. By introducing vector potentials ( ) ø , A and the vorticity î, a system of equations which are of the elliptic type for describing a velocity and pressure distribution in the channel is obtained. In this analysis, the width of the channel is taken into account and the results are compared to those obtained in the limit case when the width is much smaller or much bigger than a characteristic dimension of the channel. The results show the influence of the frequency on the fluid flow of the MHD pump.

	Development Of Real-Time Minimal Models For Belt Conveyor Systems By Uwe Druessner	[View] [Download]
Abstract: Belt conveyors are effective means of transportation in industrial systems. With the presence of speed-controlled acdrives in belt conveyor systems it is very common to meet the problem of oscillations, which cause the abrasion in mechanical parts. The task is, to find out general, real-time-minimal-models for belt conveyors, which primarily should support to design process control structures for real plants faster and more efficient.

	Equivalent Circuit Model Of The Cycloconverter-Fed Synchronous Motor By Lin Hua, Xingwei Wang, Yunping Zou	[View] [Download]
Abstract: This paper proposes a new analysis approach for analytic study of the cycloconverter-fed synchronous motor, based on the analysis of its operation characteristics. That is, the d- and q-axis variables of a synchronous motor are decomposed to low-frequency components (including aperiodic components) and high-frequency components, which can be treated separately. In this case, the resistances of rotor circuits to highfrequency components and the effect of damper winding on lowfrequency components are negligible. Therefore, by using this analysis approach, the equivalent circuit model of a synchronous motor is obtained for steady-state and quasisteady- state analysis. Furthermore, this model is used for designing current controller of the cycloconverter-fed synchronous motors drive system. The simulation results show the equivalent circuit model established in this paper is correct, which provides theoretical basis and methods for the analytical analysis of the cycloconverter-fed synchronous motor system.

	Mathematical Models Of 1h Electromechanical System For Investigations Of Transient States And Sensitivity By Z. Glowacz, K. Jaracz	[View] [Download]
Abstract: In this paper the problem of mathematical description of complex electromechanical system with 1H thyristor converter is considered. This system has been described using algebraic, logical and stiff differential equations. Created mathematical model permits to investigate the transient phenomena. On the basis of mathematical model of system the associated sensitivity models have been constructed. Associated models permit to determine the behaviour of electromechanical system with 1H converter on variations of stochastic disturbance parameters in supply voltage and system parameters. Criteria of sensitivity of system on variations of parameters have been determined. In this paper are presented sensitivity functions of electromechanical system with 1H converter. Investigated electromechanical system belongs to discrete-continuous systems.

	Sensorless A. C. Drive With Vector Controlled Synchronous Motor By Ondrej Fiser, Petr Palacky, Pavel Brandstetter	[View] [Download]
Abstract: In the paper a method for speed and position estimation for the permanent magnet synchronous motor (PMSM) were described. By using monitored stator voltage and currents and Kalman observers, it is possible to implement high - dynamic – performance PMSM drives without position and speed sensors. An Extended Kalman Filter (EKF) is a recursive optimum – state estimator which can be used for the joint state and parameter estimation of a non – linear dynamics system in real – time. The mathematical model of the vector controlled drive system in Matlab Simulink was used for simulation.

	Simulation Tools For Design And Testing Of Electric Drives By A. V. Loparev, V. M. Vodovozov	[View] [Download]
Abstract: An electric drive belongs to inhomogeneous, nonlinear and non-stationary systems, and its optimal design is related to the class of multi-criteria problems of non-linear programming that has been divided by three groups of tasks. The new eDrive software has been developed that helps in maintenance some designing stages. The interactive recursive procedure is discussed that provides the selection and testing electric drives units.