الفهرس | Only 14 pages are availabe for public view |
Abstract ents a model of linear induction motor (LIM) with consideration of electric and magnetic asymmetry due to open magnetic circuit of LIM at different connection of windings. In such model no transform of coordinates is used. This model is built using MA TLAB/SIMULINK then it is used to simulate the motor characteristics under different operating conditions and different values of motor parameters. The proposed model is used to also investigate dynamics of motor under different types of braking and a study of motor parameters on its braking dynamics is carried out. This model is also used to illustrate the speed control of LIM using V If control with different speed references. The movement ofLIM causes eddy currents in the secondary conductor sheet at the entry and the exit of the primary core. The eddy currents of the sheet cause the so-called ’end effect’ which causes not only the losses but also change in air-gap flux profile depending on the speed. In this thesis, an equivalent circuit model of LIM is developed. It is then transformed into a synchronous reference frame which is aligned with the secondary flux (d-q model). This model is built and simulated using MATLAB/SIMULINK. The simulation results of the two models (model considers magnet asymmetry without transform of coordinates and d-q model that considers end effect) are then compared. |