【作者】 白雪梅；

【导师】 陈克选；

【作者基本信息】 兰州理工大学 ， 材料加工工程， 2009， 硕士

【摘要】 等离子弧焊接是采用等离子弧作为高温热源的焊接方法,具有焊接速度快、工艺参数调节范围宽、热影响区窄、焊接变形小等优点。在研究开发现代化的电源和控制技术条件下,等离子弧焊技术是一种质量最佳、经济有效、重复性好的连接工艺。针对目前国内等离子弧焊接系统体积庞大笨重的现状,本文采用逆变电源,控制系统采用单片机控制技术代替传统的模拟控制技术,设计出了一套微机控制的小型化的等离子弧焊系统。主电路为两个逆变电源供电,控制系统以高性能单片机80C196KC为核心,实现对焊接过程的自动控制。文中阐述了等离子弧焊接设备的组成,并分析了各部分机械装置、气路、水路、焊枪在焊接中的作用,以及各组件在设计中应特别注意的问题;同时针对硅整流电源存在体积大可靠性差等问题,系统主电路采用两台逆变电源供电,这样既便于电弧工艺规范的调节,又增强系统的稳定性。详细阐述了所研制的等离子弧焊接系统中单片机控制系统的设计。分别就控制器的选型、单片机最小系统、开关量输入输出电路作了详细的分析,并从软硬件两个方面给予系统的阐述。同时,在等离子弧焊控制电路部分都进行了可靠性与抗干扰设计。分析了影响等离子弧焊接设备正常工作的各种干扰因素,并在原理图设计、PCB制作、信号传输以及程序编制的过程中采取了相应的软硬件抗干扰措施。最后,对等离子弧焊接系统的各个组成部分进行了调试分析,并给出了在试验过程中记录的照片。调试结果表明:所设计的等离子弧焊控制系统合理可行,工作稳定可靠,操作方便,抗干扰能力强,能够实现等离子弧焊接过程的自动控制。更多还原

【Abstract】 Plasma arc welding (PAW) is an advanced welding method, which adopts plasma arc as high temperature source. It has advantages comparing with other welding methods, such as high welding speed, narrow heat effect zone, little deformation of workpiece and so on. Plasma arc welding will become a kind of top-quality, economical and efficient joining technics in the conditions of the advanced electrical source and controlling technology.This paper introduces the PAW system controlled by microcontroller. Because the equipment of PAW used in our country now is more bulky, we put forward the conception of replacing it with the inverter and adopting single-chip technology instead of traditional analog technology in order to design a set of miniature PAW system. The main circuit is supplied by two power source. To realize controlling the welding process automatically, an advanced microcontroller 80C196KC is used for the center of control circuit.The constitution of plasma arc welding system, each component played roles in this system and some questions being attention to are introduced in this paper. Aimed at the shortcomings of widely application of silicon rectifier domestic, which makes the system more bulky and bad reliability, two inverter power sources are introduced as the power of PAW in main circuit. This designing not only gained convenience of adjusting parameter, but also enhanced stability of system.The designing of software and hardware about MCU controlling system is introduced in detailed in the paper, besides type choosing of controller, circuit of switch input and output are respectively analyzed. Hardware and software are both expatiated systematically. Meanwhile, Reliability and anti-interference designs are also involved in all PAW control circuits. Various noises probably appearing in the PAW process, as well as their mechanism, are analyzed systematically. Subsequently, in order to reduce their bad infections to great extent, some hardware and software measures are adopted while designing schematic chart, PCB board, code transferring and compiling program code.At last, through offline and online debugging of each component of the system, locale photos are attained and analyzed. The experiment results show that the combined control system has many advantages such as strong anti-interference ability, easy operation and reliable performance. It can meet the need of realizing automatic PAW process.更多还原