【作者】 李海波；

【导师】 何雪涛；

【作者基本信息】 北京化工大学 ， 机械设计及理论， 2003， 硕士

【摘要】 步进电机是一种进行精确步进运动的机电执行元件, 它广泛地用于工业机械的数字控制。从步进电机的矩-频特性可知,启动频率越高,启动转矩越小,带动负载的能力越差。当启动频率较高时,启动时会造成失步,而停止时由于惯性作用又会发生过冲,所以在步进电机控制中必须要采取升降速控制措施。本文根据步进电机的动力学方程和矩-频特性曲线建立系统的数学模型,采用指数规律的升降速算法,对升降速的过程进行离散处理,用定时器控制发出脉冲的时间间隔,采用查表和计算相结合的方法实现了步进电机的升降速过程的控制。本系统采用单片机为核心对步进电机进行并行控制。系统的软件设计由C51语言编程来实现,系统由十一个模块构成,各个模块完成特定的功能。用单片机仿真系统,对本系统的软、硬件进行了调试。本文还设计了检测系统用于对步进电机转速和步数的检测。最后,本系统可以实现以下功能:在显示器的提示下,由键盘输入运行的步数和稳定运行的速度;由各个功能键控制系统的运行,按启动键后,步进电机按照输入的步数进行走步;如在运行期间按停止键,则步进电机停止运行。研究表明,采用指数规律的升降速曲线将大大地提高微机控制步进电机的最高工作频率,大大缩短所需的升降速时间。更多还原

【Abstract】 The stepping motor is a precision electromechanical incremental actuator. It widely uses the digital approach for control of industrial machines. According to torque vs. speed characteristic of stepping motor, the higher startup speed is, the smaller startup torque is and then the worse the capability of driving load is. When the startup speed is higher, stepping motor will lose steps. While stopping, it will also lose steps because of inertia. So, it needs to take speed control measures on control of stepping motor. Mathematic model of the system is educed by dynamics equation and torque vs. speed characteristic of stepping motor. It adopts speed control arithmetic of exponential rule and deals with process of acceleration and deceleration via discrete method. It uses Timer to control the pulse interval at the output. It adopts method of combining checking table with computation and achieves control of acceleration and deceleration. Single-chip microcomputer that is the core of system controls stepping motor. The system is programmed by C51 language. It consists of eleven modules that each of them will achieve its corresponding function. Software and hardware is debuged by the emulational system. The test system is designed to test the rotate speed and steps of stepping motor. Finally, according to the direction of LED display, running steps and speed are input by keyboard. The system’s run is controlled by functional keys. Stepping motor will run to <WP=5>the given steps if the “start” key is pressed. Meanwhile, stepping motor will stop if the “stop” key is pressed during its running. The research shows: the method of acceleration and deceleration via exponential rule will greatly improve the highest running frequency of stepping motor and shorten the acceleration and deceleration time.更多还原