The Study On Transient Mathematic Model Of Low Speed Permanent Magnetic Linear Synchronous Motor And Self Synchronizing Analysis

Low speed permanent magnet linear synchronous motor (LPMLSM) is a new type of high efficient motor, which is basic on the change of air-gap permeability while it is slotted both stator and moving part, can work without converter, gear and driving device at a low speed. It has a series of advantages of high thrust intensity, low loss, short time-constant, rapid response, easy control and self-locking action when it brings to rest.At first the construction of LPMLSM is introduced. With the conception of air-gap permeability wave, the fundamental operating principle and low-speed condition of LPMLSM is derived, transient mathematic model of LPMLSM is established. Under reasonable assumption and in view of the construction of LPMLSM, The primary winding is discussed using Fourier analysis method by motor's winding function theory, and then three-phase winding function can be derived. Based on transient analysis for the shape of magnetic air-gap magnetic line, the expression of primary-secondary air-gap magnetic capacity and instantaneous air-gap permeability and inductance which is caused by different permeability associated with primary-second slotting is presented. Factors such as slotting effort, movement of primary-secondary, asymmetrical winds are considered by this transient mathematic model. By means of the calculating the parameter of LPMLSM, the condition of self synchronizing is established.The starting process of LPMLSM is simulated by using tool of MATLAB SIMULINK. It proves the advance of LPMLSM and the conclusion of self synchronizing possibility that is derived. At last the asynchronous process and steady state of LPMLSM is analyzed.