基于模糊理论的数控伺服系统仿真研究

Simulation on CNC servo system based on fuzzy theory

在数控伺服系统中,当系统参数发生变化或者受到外界干扰时,采用PID控制容易导致过大的超调甚至引起震荡,从而使系统的动静态性能变差。本文提出一种模糊PID控制器,它结合了PID控制和模糊控制的优点,具有较好的自适应和抗干扰能力。以本研究所研制的数控高速铣齿机Z轴位置伺服系统为研究对象,在Matlab中分别采用PID和模糊PID控制进行仿真。结果表明,模糊PID控制器具有较强的鲁棒性和抗干扰能力,更能满足数控伺服系统的性能要求。

Variation of the system parameters and external disturbances always happen in the CNC servo system. With a PID controller, it may lead to large overshoot even oscillation, then the steady state and dynamic state performance will be worse. In this paper, a fuzzy-PID controller was proposed,and it incorporated the advantages of PID control and fuzzy control ,which had good performance of adaptation and disturbance rejection. Based on the z-axis position servo system of a high-speed milling machine researched on our institute, simulations were carried out in Matlab with PID controller and fuzzy-PID controller. The results show that the system has stronger robustness and disturbance rejection with the latter, which can meet the performance requirements of the CNC servo system better.