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Based on the phase space reconstruction of welding current in short-circuiting transfer arc welding under carbon dioxide, the approximate entropy of welding current and its standard deviation have been calculated and analyzed at different welding speeds and different electrode extensions respectively. The experimental and calculated results show that at a certain arc voltage, wire feeding rate and gas flow rate, welding speed and electrode extension have significant effects not only on the approximate entropy of welding current, but also on the stability of welding process. Further analysis proves that when the welding speed and electrode extension are in an appropriate range respectively, the welding current approximate entropy attains maximum and its standard deviation minimum. Just under such circumstances, the welding process is in the most stable state. 相似文献
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对于焊接过程中常出现各种干扰,焊接条件时有变化的TIG自动焊而言,改进传感方法和控制技术是提高焊缝质量闭环控制系统控制效果的两大途径。本文在对采用CCD摄像机正面拍摄熔池图像并用微机进行图象处理,以及对参数在线自整定PID控制原理的研究基础上,设计了一种TIG焊参数在线自整定PID熔宽闭环控制系统。实验结果表明,该系统具有良好的控制特性和对焊接条件变化的适应性,可用于TIG焊焊缝质量的实时控制。 相似文献
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针对短路过渡工型CO2电弧焊系统存在本晨线性的特点,采用目前国际控制领域内应用最广的MATLAB软件,建立了“弧焊逆变器一非线性负载”系统的数字仿真模型。该模型以组合图形方式,直观、有效地表征了各一并了的特性。通过系统仿真定量地了C2电弧焊动态过程,给出功电时接电流随时间变化的仿真波形的短路过渡型CO2电弧焊系统的相平面图。应用德国产Hannover-XII型焊接过程动态分析仪所获得的实测数据与计 相似文献
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A digital arc welding power supply was designed with the advanced reduced instruction set computer machine (ARM) and embedded real-time multi-task operating system micro C/OS- Ⅱ. The ARM, with its powerful calculating speed and complete peripheral equipments, is very suitable to work as the controller of the digital power supply. The micro C/OS- Ⅱ transplanted in ARM, helps to improve the respondent speed against various welding signals, as well as the reliability of the controlling software. The welding process consists of nine tasks. The tasks of great significance on reliability of the welder, for example, the A/D conversion of current and voltage, enjoy top priority. To avoid simultaneous-sharing on A/D converter and LCD module, two semaphores are introduced in to ensure the smooth performance of the welding power supply. Proven by experiments ,the ARM and the micro C/OS- Ⅱ can greatly improve both the respondent speed and the reliability of the digital welder. 相似文献
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Based on the high speed video system with electrical signals collecting and wavelet analyzing, the welding processes under three different median currents with the same median time were detected. The experimental results show that, when the median current is higher, the input peak energy is lower. And the droplet transfer is almost in spray mode. The welding process is the stablest. 相似文献
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