The Design Of Tubular Linear Induction Motor For Lifting And Analysis Of Its Starting Characteristics

The linear induction motor is evolved from ordinary rotary induction motor, most of that are unilateral or bilateral, has been used in the area of maglev train, sending vehicles, magnetic separator etc. widely. Because of the linear induction motor with a simple structure and characteristics of controlling easily, it can be applied widely in many occasions. The study of the tubular linear induction motor for lifting in this dissertation is one among them.Based on the structure and characteristics of the tubular linear induction motor, the equivalent circuit from the perspective of energy balance has been set up and the electromagnetic design program of the tubular linear induction motor is compiled. The parameters of the equivalent circuit are calculated and the impact of the starting characteristics caused by materials of the mover and mechanical air-gap is analyzed. Also starting current and thrust of the prototype are verified by tests.The equivalent circuit considering the dynamic longitudinal end effects is set up. On this basis, voltage equation, flux linkage equation and mechanical properties equations of the motor are converted to simulation model by Matlab/Simulink software at dq0 synchronous rotating coordinate system, and the starting process of the tubular linear induction motor is simulated dynamically, which established the base for next researching on the control system for the tubular linear induction motor.The two-dimensional electromagnetic field of the tubular linear induction motor is numerically calculated by the finite element analysis software Ansoft/ Maxwell 2D, such as the magnetic induction intensity, the distribution of flux lines, current density, etc.. The starting thrust of the motor with no-load and load as well as the air-gap magnetic density in a period are calculated and analyzed and the impact of the starting characteristics caused by voltage frequency and air gap size is discussed. Finally the impact of the air-gap magnetic density caused by dynamic longitudinal end effects is also analyzed.The above calculated results provide a reference for the further theory study of the tubular linear induction motor and optimization of design.