毕业设计正文123.docx

摘 要步进电动机在无位置传感器和速度传感器系统中可以实现精确开环控制,同时又具有价格低廉、易于控制、定位准确和计算机接口易于实现等优点,被广泛应用于机械、仪表、工业控制等领域。然而,步进电动机系统的性能和运行品质在很大程度上取决于驱动电源的结构与性能,性能良好的驱动电源可以在最大程度上改善步进电机系统的性能,减少振荡与失步的发生,在高频运行时能够提供足够的转矩。步进电机多数采用绕组电流控制方式,这种方法可以提高供电电压,在高频运行时具有较好的绕组电流波形,而且可保证在一定频率范围内电流恒定,提高步进电动机的高频特性。步进电动机控制脉冲的环形分配多采用软件实现,与传统的逻辑硬件电路的实现方法相比,其控制更灵活、方便,而且易于进行升降速控制。本文在研究三相反应式步进电机工作原理和多种控制方法的基础上,采用AT89C51 单片机为主控制芯片设计了单片机控制系统,进行了三相步进电机驱动电源的设计，利用软件对步进电机进行控制,并采用恒电流脉宽调制方法（PWM）对各绕组进行了恒流控制。最后,搭建了驱动电源试验电路。关键词:三相步进电机；驱动电源；单片机； PWM 恒流控制AbstractStepper motor without position sensor and speed sensor in the system can realize precise open-loop control, at the same time, has low cost, easy to control, accurate positioning and computer interface advantages of easy to implement, is widely used in machinery, instrumentation, industrial control and other fields. However, stepper motor system performance and running quality to a large extent depends on the structure and performance of drive power supply, good performance of the drive power can be in the largest extent, improves the performance of the stepping motor system, reduce the happening of the oscillation and step out, the high frequency runtime can provide enough torque. Most stepper motor adopts winding current control method, this method can improve the power supply voltage, at high frequency operation has good winding current waveform, and can guarantee in a certain frequency range constant current, improve the high frequency characteristics of stepping motor. The annular distribution of step motor control pulse is used more softwareimplementation, compared with traditional logic hardware circuit realization method, its control is more flexible, convenient, and easy to control the speed.Based on the study of three-phase reactive stepping motor principle of work and a variety of control methods, on the basis of using AT89S51 control chip design with a single-chip microcomputer control system, the three-phase stepper motor drive power supply design, using the method of