Model Of Linear Induction Motor Research Articles

Intelligent backstepping control for linear induction motor drive

The design and properties of an intelligent backstepping control system for a linear induction motor (LIM) drive to track periodic reference trajectories are studied. First, the dynamic model of a field-oriented control LIM drive is derived. Then a feedback linearisation controller is designed in the sense of the backstepping control technique. To relax the requirement for the bound of lumped uncertainty in the feedback linearisation control law, a recurrent fuzzy neural network (RFNN) uncertainty observer is proposed to estimate the lumped uncertainty in real time. In addition, an online parameter training methodology, derived using the Lyapunov stability theorem and the gradient descent method, is proposed to increase the learning capability of the RFNN. With the proposed intelligent backstepping control system, the mover position of the LIM drive possesses the advantages of good transient control performance and robustness to uncertainties for the tracking of periodic reference trajectories. The effectiveness of the proposed control scheme is verified by both simulated and experimental results.

A method of determination of the distance between fictitious primaries in computational model of linear induction motor used in fourier series technique

The Fourier series method used to solve differential field equations in linear induction motors (LIM) is based on a computational model in which the real primary is replaced by a series of fictitious primaries distributed along the direction of motion. The distance between adjacent primaries ought to be big enough to avoid the influence of the preceding primary field on the following one. In the paper, the authors propose a method of determination of this distance but only for the computational LIM model which takes into account the finite length of primary current sheet while the iron core is assumed to be infinitely long. As an example of application of this method calculations have been made for low and high speed LIMs.

A Finite Difference Model of Linear Induction Motors, Raking into Account the Finite Length of Iron.

The electromagnetic equations of the motor are written, then transformed by the finite difference technique. Both the infinite extent of the secondary and the finite extent of the iron are taken into account by the partition method. Actual width of the iron and the secondary are considered. Most of the unknowns are eleminated by the use of a transmission matrix ; thus, the final system of algebric equations is small enough to be solved by a classical inversion technique. An interesting correspondance is established between the eigenvalues of the transmission matrix and the poles of some expressions which are obtained when Fourier transform technique is used.

A Finite Difference Model of Linear Induction Motors, Taking into Account the Finite Length of Iron

The electromagnetic equations of the motor are written, then transformed by the finite difference technique. Both the infinite extent of the secondary and the finite extent of the iron are taken into account by the partition method. Actual width of the iron and the secondary are considered. Most of the unknowns are eleminated by the use of a transmission matrix ; thus, the final system of algebric equations is small enough to be solved by a classical inversion technique. An interesting correspondance is established between the eigenvalues of the transmission matrix and the poles of some expressions which are obtained when Fourier transform technique is used.

Non-Uniform Power Distribution in Linear Induction Motors Due to End Effects

This paper presents experimental data showing the effects of electrical and magnetic discontinuities on linear induction motor (LIM) performance. The power distribution along the LIM, the effect of the machine length, and the validity of assuming a LIM model in which the iron extends beyond the bound of the winding were investigated.