铝合金脉冲MIG焊干伸长二自由度PID控制

摘要

Dual freedom PID control of wire dry extension in pulse MIG welding of aluminum alloy was investigated. On the basis of designed response of ratio of wire feeding velocity to its dry extension to stepinput and subsequently obtained identification model, the controlling effect with dual freedom PID algorithm and conventional PID algorithm was simulated and compared in the case of optimal parameters. On the basis of simulation result and by using Matlab/Simulink and xPcTarget to set up the real-time objective environment, the welding was performed. A dual freedom PID welding control system was established and real-time control was investigated. Its result showed that in the process of pulse MIG welding of aluminum alloy the dual freedom PID controller exhibited a higher precision and faster response, and the stability of wire dry extension could effectively be controlled, meeting the requirement of stability in the process of aluminum alloy welding.%针对铝合金脉冲MIG焊接过程中干伸长的二自由度PID控制进行研究.在设计送丝速度阶跃对干伸长响应,获得辨识模型的基础上,分别采用二自由度PID和常规PID算法,在最佳参数条件下对其控制效果进行对比仿真.在仿真结果的基础上利用Matlab/Simulink、采用xPCTarget的实时目标环境进行焊接,建立基于二自由度PID的焊接控制系统并进行实时控制研究.结果表明:在铝合金脉冲MIG焊接过程中,二自由度PID控制器具有更高的精度和更快的响应速度,可以有效地控制焊丝干伸长的稳定性,能满足焊接过程的稳定.