数控机床的准闭环控制技术

针对以步进电机作为驱动电机的数控机床开环系统存在的一些问题,诸如伺服精度低、失步误差不能补偿等,文章提出了一种新的控制技术--准闭环控制.采用这种控制方式,可以获得类似闭环系统的控制精度和开环系统的稳定性.文章选用MCS-51单片机作为控制核心,直线光栅测量位移,在普通车床上建立了一种新型的准闭环控制系统.实践表明,该系统的控制精度高、稳定性好、性价比高.它适合于经济型数控机床,应用前景十分广泛.

Quasi-close Loop Control Technique for CNC Machine Tools

In view of the problems existing in open loop system of CNC machine tools with stepper motor as driving motor, such as lower servo precision, without compensation for step-losing of stepper motor and so on, this paper presents a new technique called quasi-close loop control. With the help of the method, the control accuracy similar to that of close loop system can be obtained and the system has the same stability as that of open loop system. With MCS-51 single-chip microcomputer as control unit and grating scales measuring displacement, a new type of quasi-close loop control system is built on universal lathe. The practice shows that quasi-close loop control system has advantages such as high control accuracy, good stability and high ratio of performance to price. It is suited to economical CNC machine tools and has wide application prospects.