【作者】 韩铮；

【导师】 张润和；

【作者基本信息】 内蒙古工业大学 ， 电力电子与电力传动， 2009， 硕士

【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,利用MATLAB/Simulink对恒流控制电路进行了仿真研究,给出了仿真结果。采用AT89S51单片机为主控制芯片设计了单片机控制系统,利用软件环分方法对步进电机进行控制,并采用恒电流脉宽调制方法对各绕组进行了恒流控制。最后,搭建了驱动电源试验电路。仿真结果表明,该系统可以在一定频率范围内实现电流恒定控制。在此基础上,确定了给定电压的变化范围和不同频率下的有效调节范围。实验结果可以看出,通过对绕组电流恒定控制大大改善了步进电机高频特性。更多还原

【Abstract】 Because of the advantages in accurate control to open-loop system without speed sensor and position sensor, and the advantages in many aspects,such as in price, control, positioning and computer interface, stepper motor are widely used in the fields of mechanical, instrument and industrial control. The performance of stepper motor system depends on a great extent on the structure and properties of the driving power. That can be improved in the maximal degree by using an qualified driving power.which can reduce the influence of concussion, out of step and provide enough torque in high-frequency operation.Today, Winding current control is a most commonly control mode at present. Power supply voltage will be improve by using this method, that sure to have a better winding current waveform which make current constant in a frequency range and have a better performance in high frequency part. A good constant-current control circuit also is the foundation of subdivision driving. The pulse annular allocation of stepper motor usually to implement by software, compared to conventionally method used logic circuit, the control more flexible,convenient and easy control in speedup and speeddown process.Based on researched stepper motor mathematical model, working principle and many control methods of three-phase reaction stepping motor. A study about constant current control circuit is made in this paper by simulation tools MATLAB/Simulink. the PI parameters are chosen and simulation results are given. The control part which adopted to realize loop distributor is designed based on microprocessor AT89S51.At the same time,a circuit about driving power is designed using a fixed frequency PWM circuit TL494 and a mosfet driver circuit IR2110. Finally, a printed circuit board has been fabricated and a experiment circuit about driving part is build.The results of the simulation to illustrate that winding current can be constant in a frequency range. Based on the results, the range of voltage variation and the range of the tuning range under a special given voltage have been defined. Under the results of the experimental, the Torque-frequency characteristic at the range of high frequency can be improved.更多还原