Abstrakt

Two-Dimensional Analytical Model and Control of Linear Induction Motor

Ehsan Shirzad*

Through electromagnetic forces, Linear Electric (Electromagnetic) Machines (LEMs) can directly convert electrical energy into linear mechanical kinetic energy (vice versa). Linear motion is especially common in industry. LEM was developed in his 19th century, but did not become widely used in industry until 1960 because it required power electronics (no mechanical transmission) for control. However, LEMs require power electronics for linear position, speed, and/or force control to achieve better performance than rotary electric motors with mechanical transmissions. After 1960, LEM continued to improve. The lift and drive forces of a two-phase Linear Induction Motor (LIM) are controlled by varying the phase angle between the two phases. In this article, we derive the magnetic flux density, secondary current density, and propulsion and levitation force densities in the air gap. The mean force equation is derived by summing the force density over a quadratic length using twodimensional magnetic field analysis and is used to simulate the performance of a linear induction motor. We investigate the effect of changing the phase angle on the secondary current density, perpendicular magnetic flux density component, and tangential magnetic flux density component. Furthermore, these phase-shifting effects are extended to include his two components of force (levitation and propulsion). Calculations are performed using MATLAB programs and displayed graphically.