【作者】 李皞东；

【导师】 王成元； 夏加宽；

【作者基本信息】 沈阳工业大学 ， 电机和电器， 2002， 硕士

【摘要】 在电火花加工领域中，长期以来都是借助于传统的“旋转电动机+滚珠丝杠”的间接进给方式，获得所需的直线运动形式。这种加工方式由于速度低和加工精度不高，无法满足当今数控机床的高速和超精密加工技术的要求。 永磁直线电机的直接驱动方式可赋予电火花机床优良的性能，能实现高速和高加速度加工，解决了长期困扰电火花加工业的深型腔加工难的问题。然而，由直线电机端部效应引起的扰动，也成为影响着机床主轴系统性能的主要因素。 本文首先对永磁直线电机进行了优化设计。编写基于ANSYS的电磁场有限元分析程序，计算主要由直线电机端部效应引起的波动推力。在矢量控制运行下，分别计算了电机在空载时和在通以不同电流时的由端部效应引起的波动推力，并且分析了电流大小对端部效应的影响。采用齿谐波低频调制的设计方法，来削弱直线电机固有的端部效应，使推力的波动减小，并进行了多方案计算，得出比较好的设计方案。然后，又对基于数字信号处理器(DSP)的电机控制系统进行了分析，设计了DSP系统的硬件电路，并编写和调试了空间磁场定向控制和空间矢量脉宽调制(SVPWM)的DSP系统的软件，为直线电机现代控制策略的具体实现奠定了基础，并提出了对端部效应进行补偿的控制方法。最后，设计了测量直线电机推力的实验装置，得出了电机推力的实验数据。 从以上的分析和计算得出，随绕组电流幅值的增加，端部效应影响电机推力的波动趋势不变，空载端部效应是永磁直线电机端部效应的主要部分。提出的采用多极电机方式；初级与次级极距不等的方式；齿谐波低频调制方式和改变电机两端部磁导的方式等电机的设计原则和方法，都可有效地削弱端部效应，减小推力的波动。利用DSP的强大运算能力和丰富的片内外设，可满足电机的先进控制策略在具体实现时的实时性要求。更多还原

【Abstract】 In the field of the electric discharge industry manufacture, the conventional "rotation motor + threaded spindle" movement mode is the leading condition, that gets the indirect linear movement. Because of its lower velocity and precision, this mode is not fit for the demand of the higher velocity and precision technology of the numerical control machining.The direct drive mode based on the permanent magnet (PM) linear motor can be provided for the best performance of the electric discharge machining. It finishes the high speed and high acceleration cutting, and solves the difficult problem of manufacturing deep slot mould. However, the disturbance of the linear motor’s end effect is the main factor of affecting the machining performance.First, in this paper the design of PM linear motor is optimized. The electromagnetic finite element software is programmed using the ANSYS and the thrust is calculated that the linear motor’s end effect brings. In the vector control, both the no-load thrust and the thrust with the different current are calculated, and the end effect influenced by the current magnitude is analyzed. The low-frequency slot harmonic modulation is used to weaken the end effect or decrease the wave of the thrust, and the many projects are designed or the better project is selected. Besides, the motor control system based on the digital signal processor (DSP) is analyzed. The hardware circuit about the DSP system is designed. The DSP control software is programmed on the field magnetic orientated control and the space vector pulse width modulation (SVPWM), that establishes the’basis for implementing the modern control principle. The method of compensating the end effect is presented. Finitely, the experiment device of measuring the thrust is designed, and the experiment data of the thrust is obtained.In conclusion, when the current of the winding is increased, the tendency of the end effect-thrust is unchangeable, the no-load end effect is the main part of the PM linear motor’s end effect. The more poles mode, the unequal pole width mode; the low-frequency slot harmonic modulation mode and the mode of changing end magnetic conductance are presented, and these designing method can efficiently weaken the end effect and decrease the wave of the thrust. The high-speed calculation function and the inner integrated peripherals of DSP are used. DSP can satisfy the real-time demand of the advanced control principle when these are implemented.更多还原