摘要
数控机床伺服系统的性能是数控机床可以达到的加工效率和加工精度的决定因素。因此在静态设计之后必须进行动态仿真和校正设计。由于PID(proportion-integral-differential)控制器具有原理简单、使用方便、适应性强和鲁棒性强等特点,采用PID控制器作为校正装置。在均匀设计的基础上,采用二阶响应面模型拟合性能指标超调量和上升时间与控制器参数之间的关系,经假设检验说明该模型显著性非常明显。利用遗传算法分别针对2个指标寻找最佳的控制器参数,计算上升时间的最小值为0.077 s,实际仿真时间为0.12 s;计算超调量的最小值为0.063%,实际仿真结果为1.24%。利用叠加等高线图,寻找同时满足2指标的最优控制器参数。说明采用响应面模型优化PID控制器参数是合理可行的。
Performances of servo system are the key factors, which determine the best process accuracy and efficiency that computer-numerical-control （CNC） machine tools can reach, and therefore it is absolutely necessary to conduct dynamic simulation and design corrector after static design. PID （proportion-integral-differential）-controller as a correction device is adopted, for it shares good performances such as simple principle, easy to use, adaptability and robustness. Based on uniform experiment design, the correlation between performance indicators （including overshoot and rise time） and PID-controller parameters is respectively fitted using second-order response surface methodology （RSM） , with high significance by hypothesis testing. Based on second-order RSM, using genetic algorithm （GA）, optimal parameter values can be calculated respectively aiming at minimum rise time and minimum overshoot, with the result of minimum rise 0. 777 seconds against actual simulation value 0.12 seconds and the result of minimum overshoot 0. 063% against actual simulation value 1.24% . Optimal parameter values both meeting the requirements of overshoot and rise time can be obtained, employing superimposed contours. This proves RSM reasonable and feasible in PID-controller parameter tuning.
出处
《机械强度》
CAS
CSCD
北大核心
2013年第3期263-269,共7页
Journal of Mechanical Strength
基金
江苏省科技支撑计划(DE2010365)资助项目~~
