基于辅助变量法对激光焊接的辨识和控制

摘要

Mathematical model of Laser Welding Process has stronger nonlinearity. Accurate model cannot be obtained by conventional identification methods for Laser Welding Process. In order to remove the difficulties in modeling and controlling of laser welding process, a nonlinear identification method based on instrumental variable method was presented in this paper, and a nonlinear model for Laser Welding Process was obtained. On the basis of this model , an Adaptive Pole Placement Indirect Self-tuning Regulator Control was introduced. Simulation results show that the proposed identification method and control method are effective. The output of process can track the desired signal. The control method is simple, precise and robust to disturbances.%激光焊接过程数学模型具有较强的非线性,焊接激光系统要求稳定的动特性.通常的辨识方法无法得到精确数学模型.针对激光焊接过程非线性系统难于建模和难于控制的问题,为了提高控制焊接质量,提出了根据辅助变量法的非线性辨识方法,辨识出了具有典型非线性的焊接过程模型.还结合自适应极点配置间接自校正控制器的设计方法.仿真结果表明所提出的辨识方法和控制方法非常有效,不仅可以保证激光焊接过程跟踪指定的期望值,还具有控制算法简单,控制精度高和抗干扰能力强等优点,为系统设计提供了可靠依据.