基于模糊和PI控制的MIG焊接电源设计  

Design of Fuzzy and PI Control Based MIG Welding Power Source

作　　者：庞清乐[1] 王永强[1] 

机构地区：[1]山东工商学院信息与电子工程学院,山东烟台264005

出　　处：《控制工程》2012年第3期507-510,534,共5页Control Engineering of China

基　　金：国家自然科学基金(50777040);中国博士后科学基金(20090461204);山东省自然科学基金(ZR2010EL030)

摘　　要：针对模拟控制和单片机控制的脉冲MIG(Metal Inert Gas)弧焊电源控制系统灵活性差、控制精度低和可靠性差等缺点,设计了基于模糊和PI控制的MIG焊接电源控制系统。为了提高焊接电流的控制精度,控制焊接电流的PI参数在一个周期的不同阶段应该是不同,所以该系统的焊接电流控制采用变参数PI控制方法。在不同焊接条件下的PI参数由专家系统确定。为了提高电弧弧长的稳定性,电弧电压控制采用模糊控制方法。模糊控制和变参数PI控制算法分别由数字信号控制器(DSC)和现场可编程门阵列(FPGA)实现。最后,介绍了系统的硬件电路设计和软件流程。利用焊接铝板对该系统进行了测试,测试结果表明,基于模糊和PI控制的MIG焊接电源控制系统动态响应快、可靠性高、弧长控制稳定。A Control system based on fuzzy and PI control for pulsed MIG （ Metal Inert Gas ） arc welding power source is designed, which aims at improving some deficiencies in the control system based on analogous control technology and single - chip control technology, such as poor flexibility, control precision and reliability. To improve the control precision of welding cmTent, the PI parameters should be adjusted in different sections of a period. So the PI controllers with varying parameters is applied to control the welding current. The parameters of PI controller in different welding conditions are determined by an expert system. To improve stability of arc length control, a fuzzy controller is used to realize the arc voltage control. In the proposed control system, a digital signal controller （DSC） and a field programmable gate array （FPGA） realize fuzzy control algorithm and varying parameter PI control algorithm, respectively. Finally, the hardware circuit and the flow chart of the control system are described. The system is verified by welding aluminum board experiment. The experimental results show that the proposed hybrid control system based on fuzzy and PI controllers for MIG welding power source demonstrates some advantages on quicker response, better reliability and stability.

关 键 词：模糊控制 PI控制 MIG焊接电源 DSC FPGA 

分 类 号：TP27[自动化与计算机技术—检测技术与自动化装置]