Study On Magnetic Equivalent Circuit Of Single Phase Tubular Linear Motor

First of all,the development history and the research status of the linear motor are introduced in this thesis,it also compares the characteristics of different common linear motors.There is no transverse end effect in the tubular linear motor,which exists in conventional linear motors inherently.What's more,the low manufacturing cost and long service life have shown broad application prospect of the tubular linear motor.However,the electromagnetic characteristic of the tubular linear motor is very complicated and cannot be described with precise mathematical expressions.Although the result of finite element analysis(FEA)method is accurate compared with the experimental results,the calculation time is too long and the demand for computer hardware is also too high,which lengthens the design cycle of the tubular linear motor.Magnetic equivalent circuit(MEC)method has a short calculation time and can be used as a preliminary calculation for the motor design when the calculation error is acceptable.So MEC method is utilized to analyze the electromagnetic characteristic of the tubular linear motor in this thesis.A single phase tubular switched reluctance linear motor(TSRLM)and a single phase tubular permanent magnet linear motor(TPMLM)are studied in this paper.By analyzing the flux linkage distribution with the finite element software FLUX,the 2-D and 3-D MEC models of the two motors are established,respectively.The accuracy of the proposed MEC model is proved by experimental verification.According to the geometric parameters of the single phase TSRLM and the single phase TPMLM,the 3-D finite element model of the two motors are built in the finite element software FLUX.The flux linkage distribution and the magnetic induction intensity of the single phase TSRLM and the single phase TPMLM at different mover positions are obtained with 3-D finite element calculation,which is the foundation for establishing the MEC models of the two aforementioned motors.Based on the 3-D finite element analysis,the 2-D MEC models of the single phase TSRLM and the single phase TPMLM are built.By decomposing the two motors into smaller reluctances,the expression of each reluctance is given to calculate the flux linkage characteristic of the single phase TSRLM and the single phase TPMLM.The Gauss-Seidel iteration is utilized in order to solve the saturation in the two motor,which makes the results calculated with 2-D MEC model more reasonable.By taking the leakage flux linkage of the single phase TSRLM and the single phase TPMLM into account,the 3-D MEC models of the two motors are established based on the 2-D MEC models.Then the 3-D MEC models of two motors are analyzed,and the flux linkage data of the two motors are calculated.Compared with the results calculated with 2-D MEC model,the results calculated with 3-D MEC model is more accurate.The simulation models of the single phase TSRLM and the single phase TPMLM are built in MATLAB/Simulink.The flux linkage data calculated with MEC models are imported into the flux linkage calculation model of the two motors.The voltage and current waveforms of the single phase TSRLM and the single phase TPMLM at different speeds are obtained.Experimental verification of flux linkage,static force,voltage and current of the two motors are conducted.The results show that the simulation results coincide with the corresponding experimental results in the same condition,which verifies the correctness of 2-D and 3-D MEC models,and proves that the 3-D MEC model is more accurate.