Mathematical modelling of Linear Induction Motor with and without considering end effects using different reference frames
01 Jun 2016-pp 1-5
TL;DR: A mathematical model based on d-q axes equivalent circuit is used to describe the dynamic behavior of Linear Induction Motor with and without considering end effects to help understand the transient and steady state behavior of the LIM.
Abstract: In this paper, a mathematical model based on d-q axes equivalent circuit is used to describe the dynamic behavior of Linear Induction Motor (LIM) with and without considering end effects. The model is simulated using two different reference frames namely stationary reference frame and synchronously rotating reference frame for better understanding of the transient and steady state behavior of the LIM. This transient and steady state analysis helps in deciding the reference frame based on the problem to be resolved, variables to be studied and the machine type either single-machine or multi-machine system. The model is simulated using MATLAB/SIMULINK tools as it is the sophisticated way of implementing the dynamic equations using function blocks. The control for Linear Induction Motor like vector control, position control and sliding model control can be applied to this model.
Citations
More filters
01 Jun 2018
TL;DR: In this paper, an electromagnetic torque of the squirrel cage induction generator during the connection with a power grid is investigated and the reduction method of the pulse amplitude by using the series RL branch is also presented.
Abstract: The connection of the induction machine with a power grid causes pulses of an electromagnetic torque with a high gradient. This effect is especially dangerous in systems with a transmission gear of a large ratio, like in hydropower schemes, because the torque pulses can generate very high stress on the gearbox and turbine bearings. In this paper an electromagnetic torque of the squirrel cage induction generator during the connection with a power grid is investigated. The mono-harmonic circuit model of the squirrel cage induction generator is prepared and verified on the laboratory test bench. This model is used to analyze the electromagnetic torque curve. Special attention is put into investigation of a torque pulse amplitude. The reduction method of the pulse amplitude by using the series RL branch is also presented.
2 citations
Additional excerpts
...The machine model for the purpose of dynamic states investigation can be generalized by considering only a basic component of the gap field [6, 8-20]....
[...]
References
More filters
01 Jan 2002
TL;DR: Theory of brushless dc motors and dc machines is discussed in this article, where the authors present a general framework for electric machine analysis based on basic principles for Electric Machine Analysis.
Abstract: Preface.Basic Principles for Electric Machine Analysis.Direct--Current Machines.Reference--Frame Theory.Symmetrical Induction Machines.Synchronous Machines.Theory of Brushless dc Machines.Machine Equations in Operational Impedances and Time Constants.Linearized Machine Equations.Reduced--Order Machine Equations.Symmetrical and Unsymmetrical 2--Phase Induction Machines.Semicontrolled Bridge Converters.dc Machine Drives.Fully Controlled 3--Phase Bridge Converters.Induction Motor Drives.Brushless dc Motor Drives.Appendix: Trigonometric Relations, Constants and Conversion Factors, and Abbreviations.Index.
3,147 citations
"Mathematical modelling of Linear In..." refers background in this paper
...A new variable calledZero sequence components is introduced for the inversion of Park's transformation and for handling the unbalanced voltages [6]....
[...]
21 Nov 2005
TL;DR: In this article, an equivalent circuit model of linear induction motor (LIM) is developed following Duncan's per phase model, which is then transformed into a synchronous reference frame which is aligned with the secondary flux.
Abstract: The movement of a linear induction motor (LIM) causes eddy currents in the secondary conductor sheet at the entry and the exit of the primary core. The eddy currents of the sheet tend to resist sudden flux variation, allowing only gradual change along the airgap. Hence, the so-called 'end effect' causes not only the losses but also airgap flux profile variation changes depending on the speed. In this work, an equivalent circuit model of LIM is developed following Duncan's per phase model. It is then transformed into a synchronous reference frame which is aligned with the secondary flux. Also, a field orientation control scheme is developed which accounts for the end effect. The validity of the proposed LIM model is demonstrated by comparing experimental and simulated voltage current relations. With the proposed control scheme, the (secondary) flux-attenuation problem due to the end effect is shown to be resolved in the high-speed range.
161 citations
"Mathematical modelling of Linear In..." refers methods in this paper
...For control purposes, system variables in DC quantities are preferred compared to the available sinusoidal variables [9]....
[...]
TL;DR: Using the series circuit, the performance of the SLIM was assessed in a similar manner to a rotating induction machine and a 4-kW SLIM prototype was tested, which validated the simulation technique.
Abstract: The derivation of the equivalent circuit for a single-sided linear induction motor (SLIM) is not straightforward, particularly if it includes longitudinal end effects from the cut-open primary magnetic path, transversal edge effects from the differing widths between the primary lamination and secondary sheet, and half-filled primary slots. This paper proposes an improved series equivalent circuit for this machine. The longitudinal end effects are estimated using three different impedances representing the normal, forward, and backward flux density waves in the air gap, whose two boundary conditions are deduced by introducing the conception of magnetic barrier surface. The transversal edge effects are accounted for by correction coefficient Kt and air-gap flux density correction coefficient Kb. Using the series circuit, the performance of the SLIM was assessed in a similar manner to a rotating induction machine. A 4-kW SLIM prototype was tested, which validated the simulation technique.
122 citations
"Mathematical modelling of Linear In..." refers background in this paper
...The two-axis modelling of UM is needed to avoid the time varying nature of inductances which leads to complexity in the modelling process [8]....
[...]
TL;DR: Case studies are used to demonstrate that the choice of the reference frame depends on the problem to be solved and the type of computer available (analog or digital).
109 citations
Book•
01 Jan 1985
TL;DR: The classification of linear machines can be found in this paper, where the authors classify linear machines into four classes: low-speed linear induction motors (lim's), low speed linear inductors (lims'), low speed Linear Synchronous and Stepper Motors (LSHM's), Low-Speed dc Linear Induction Motors (Lim's) and Low Speed dc Linear Motors (LIMs) for Ground Transportation.
Abstract: Introduction and Governing Equations Classification of Linear Machines Certain Applications Low- Speed Linear Induction Motors (lim's) Low-Speed Linear Synchronous and Stepper Motors Low-Speed dc Linear Motors Linear Induction Liquid-Metal Systems Linear Homopolar dc mhd Systems Linear Induction Motors (Lim's) for Ground Transportation Linear Inductor Motors for Transportation Active Guideway Synchronous Motors (LSHM's) for Transportation Active Guideway Superconducting Synchronous Motors (LSCM) for Transportation Active guideway dc Linear Motors for Transportation Linear-Motion Electromagnetic Levitators (LEL) Linear-Motion Electrodynamic Levitators (EDL) The Electrodynamic Wheel (EDW) Linear-Motion Uncontrolled Electromagnets Appendixes.
99 citations