基于可编程控制器的转速测量及步进电机升降速控制研究

为了实现动设备转速的实时监测，本文通过可编程控制器(PLC)的时基中断和计数器中断功能分别实现了基于数字式频率法和频率/周期法的转速测量。通过高速脉冲输出功能研究设计出了幂函数型、直线型以及指数型升降速曲线，对步进电机进行平稳可靠的控制。以活塞式压缩机满负荷的情况为例，通过具体程序设计和实验，采用频率/周期法成功实现了对压缩机曲轴转速的实时监测；并运用直线型控制曲线，实现了步进电机平稳的升速控制。

Speed measurement and acceleration/deceleration control for a stepper motor based on a programmable logic controller

In order to achieve real-time monitoring of the speed of rotating machines,speed measurement based on digital frequency and frequency/cycle methods has been realized using the time base interrupt and speed counter interrupt function of a programmable controller.The acceleration and deceleration curves for the stepper motor including the types of power function—linear and exponential—were designed using the high-speed pulse output function to achieve smooth and stable control of the stepper motor.Taking the situation when the reciprocating compressor was in full load as an example,by means of specific program design and experiment,the real-time monitoring of the compressor crankshaft speed was realized successfully by the use of the frequency/cycle method.A smooth acceleration control for the stepper motor was then achieved by applying a linear control curve.