圆筒直线感应电机电磁振动响应特性分析

Analysis of electromagnetic vibration response characteristics of tubular linear induction motor

针对某电磁发射用圆筒直线感应电机的电磁振动响应特性问题进行了分析。首先,建立了直线电机二维电磁场分层子域模型,通过涡流场有限元仿真验证了模型的精确性,并基于麦克斯韦张量法和洛伦兹力法推导了电磁激振力表达式,利用二维傅里叶分解得到定子电磁力时空分布特性;然后,基于有限元法构建了发射电机定子三维动力学模型,模态计算结果与试验吻合良好,采用有限元法进行电磁振动谐响应计算,结果有效性通过稳态动子堵驻通电试验得到了验证,证明了发射电机定子结构可以简化为理想薄壁圆柱壳,电磁振动响应主要由轴向呼吸模态决定;最后,基于简化模型对比分析了电磁振动响应影响因素,结果表明:电磁激振力径向分量和轴向分量均为结构响应的主要贡献源,而与电磁力波轴向模数呈负相关规律。

The electromagnetic vibration response characteristics of a tubular linear induction motor(TLIM)for electromagnetic launch were analyzed.Firstly,the layered electromagnetic model of TLIM was established,and the accuracy of the model was verified by finite element simulation.Based on Maxwell tensor method and Lorentz force method,the expression of electromagnetic excitation force was derived.The time-space distribution characteristics of stator electromagnetic force were obtained.Then,based on the finite element method,a three-dimensional dynamic model was built,and the modal calculation results were in good agreement with the test.Abaqus software was used to calculate the harmonic response of electromagnetic vibration,and the results were verified by mover blocking test.The numerical calculation results further show that TLIM stator structure can be simplified as a thin cylindrical shell,its dynamics response characteristics are mainly determined by the axial breathing mode.Finally,the electromagnetic vibration response influencing factors were compa-ratively analyzed based on simplified models,the results show that the radial component and axial component of electromagnetic excitation force are the main contribution sources of vibration,but is mainly negatively correlated with the axial modulus of electromagnetic force wave.