Research on Cogging Force Suppression for Toroidal PMLSM Based on Disturbance Observer

For a new type of toroidal permanent magnet linear motor(TPMLSM), this paper analyzes the thrust fluctuation in the constant acceleration operation of the motor from the Angle of the cogging force of the linear motor. For the motor whose structure has been determined and processed, the structural parameters of the motor cannot be changed, and its performance cannot be improved from the perspective of the motor body.Therefore, this paper tries to consider the influence of the cogging force on the normal operation of the motor from the perspective of control. In this paper, starting from the body structure of motor, first on the annular linear motor of the cogging force characteristics were extracted, and its expression is obtained by Fourier decomposition, then investigated considering the cogging force and does not consider the cogging force control of motor model, it can be seen that the control performance deteriorates significantly after considering cogging force of the motor, and the acceleration fluctuation increases significantly during the operation of the motor. On this basis, disturbance observation algorithm is introduced, and feedforward compensation is carried out by extracting the characteristic values of the disturbance model. The results show that the disturbance observer can suppress the thrust fluctuation caused by the motor cogging force to a large extent, and it can reduce the peak-to-peak value of the thrust fluctuation by more than 85% during the motor acceleration operation.

径向充磁圆筒永磁直线同步电机磁场和推力解析计算

介绍了一种基于标量磁位分离变量法(圆柱坐标)的径向充磁圆筒永磁直线同步电机磁场解析计算方法。利用该解析法理论分析了无槽电机的气隙磁场,得到了气隙磁场的轴向和径向磁场分布的解析结果;同时对有槽电机引入了卡特系数并利用许-克变换构造了考虑齿槽效应的气隙相对比磁导函数,得出了径向磁通密度的解析表达式;此外,文中还利用解析法计算了无槽电机的推力;通过有限元数值算法对磁场和推力进行计算,结果表明,该电机气隙磁场及电磁推力的两种计算方法的结果误差很小,验证了解析法的正确性和实用性。最后给出了无槽型实验样机的径向磁场分布以及电机额定负载时的推力实验结果,验证了样机分析和设计的正确性。

圆筒型永磁直线同步电机矢量控制系统仿真

针对圆筒型永磁直线同步电机(TPMLSM),提出了一种基于空间电压矢量脉宽调制(SVPWM)的矢量控制系统,采用速度、电流双闭环的控制方案,实现对TPMLSM的控制,并进行了仿真研究。Magnet建立TPMLSM有限元模型,Simulink构建基于SVPWM的双闭环矢量控制系统,利用Magnet与Simulink联合仿真接口,建立Magnet与Simulink联合仿真模型。仿真结果表明所采用的控制方法正确可行,控制系统具有良好的控制性能。

潜油永磁直线电机单边磁拉力分析与计算

针对圆筒形永磁直线电机的偏心带来极大单边磁拉力、导致动定子之间的摩擦力高达数千牛顿的问题,建立了圆筒形永磁直线电机模型,分析了圆筒形永磁直线电机的结构特点与电机单边磁拉力产生的原因.采用磁路法分析电机偏心时的气隙磁场,利用麦克斯韦张量定理推导出空载下圆筒形永磁直线电机的结构参数和偏心参数与单边磁拉力的关系,并根据推导结果计算出电机单边磁拉力.结果表明,该解析方法具有一定的正确性和准确性.

基于辅助铁心的永磁直线同步电机边端力最小化

针对永磁直线同步电机(PMLSM)边端力最小化问题,提出在初级铁心两端增加辅助铁心的方法,有效削弱PMLSM的边端力。首先分析了边端力产生的机理,对齿壁上所受电磁力进行解析研究。当初级铁心两端辅助铁心高度为一个气隙长度,且辅助铁心长度为1/4永磁极距时,边端力有最小值。以一台36槽12极轴向充磁圆筒永磁直线同步电机(TPMLSM)为例,进行有限元仿真分析和试验测试,边端力的有限元分析值和试验值较吻合,证实了所提方法能够有效削弱PMLSM边端力,为该类电机边端力最小化提供了一种简单有效的技术手段。

多段式初级铁芯圆筒型永磁直线电机齿槽力研究

针对永磁直线电机的推力波动问题,首先针对整数槽绕组多段式初级铁芯结构圆筒型永磁直线电机,提出了采用初级铁芯依次沿纵向移距的方法削弱电机的齿槽力,并基于能量法推导了初级铁芯模块移距法削弱齿槽力的机理,给出了初级铁芯模块移距的计算公式;其次,针对初级铁芯模块移距引起各段相电动势的分布的情况,给出了空载电动势等效分布系数的计算公式;最后,进行了有限元分析及试验。结果表明:初级铁芯模块移距后,电机的齿槽力得到了有限的抑制,大大降低了空载电动势中的谐波含量,相空载电动势波形更加正弦化。

轴向充磁圆筒型永磁直线同步电机气隙磁场解析计算

介绍了一种基于许-克变换法的轴向充磁结构圆筒型永磁直线同步电机(TPMLSM)气隙磁场解析计算方法。首先采用许-克变换法计算出无齿槽时电机的气隙磁场;然后利用许-克变换法求取初级铁心开槽时的气隙相对比磁导函数,分析铁心开槽对气隙磁场的影响;最后通过无齿槽时的气隙磁场与有齿槽时的气隙磁场相对比磁导函数得到有齿槽时电机的气隙磁场分布。同时给出了该种充磁结构TPMLSM气隙磁场解析计算表达式,并以1台36/12极槽配合轴向充磁TPMLSM样机进行试验。试验结果证明空载气隙磁场的有限元分析值与解析值较吻合,空载电动势(EMF)计算值、试验测试值、有限元分析值一致。

Magnetic field and performance analysis of a tubular permanent magnet linear synchronous motor applied in elevator door system

A novel elevator door driven by tubular permanent magnet linear synchronous motor (TPMLSM) is presented. This TPMLSM applies axial magnet array topology of the secondary rod, air-cored armature windings and slotless structure of the forcer to improve the stability of the thrust. The influence of two major dimensions, the pitch and radius of the permanent magnet (PM), on magnetic field was studied and the best values were given by the finite element analysis (FEA). The magnetic field, back EMF and thrust of the motor were analyzed and the PM size was optimized to reduce the harmonic components of the magnetic field and improve the performance of the motor. Predicted results are validated by the experiment. It is shown that the performance of the motor and the novel elevator door system is satisfying.

圆筒型直线电磁复进机性能与控制特性研究

针对传统液气式复进机易破损漏气、易污染变质、可控性差等问题,提出了一种圆筒型直线电磁复进机。通过对火炮复进过程进行分析,确定了电磁复进机技术要求与关键尺寸参数。设计了圆筒型直线电磁复进机结构,并利用Maxwell软件建立电磁复进机有限元模型,分析了电磁复进机充磁方式和关键尺寸参数对推力特性的影响。建立了电磁复进机数学模型,设计了一种改进型自抗扰控制算法,对火炮复进过程进行控制。仿真结果表明,所设计的圆筒型直线电磁复进机能够满足火炮复进过程需求,改进型自抗扰控制算法实现了火炮复进过程快速准确控制。研究成果为可控式磁阻尼反后坐装置的设计提供了重要理论支撑。