Research on a 50 kW digital inverter type plasma cutting power supply

To improve energy transfer efficiency and quality controllability of plasma cutting process of thick plate, a 50 kW digital inverter type plasma cutting power supply is developed. The power supply main circuit is composed of two similar power electronic building blocks, using full-bridge high frequency inverter topology to achieve efficient energy transformation. To realize accurate digital control of the plasma cutting power supply and cooperative work of the two power electronic building blocks, the Cortex-M4 type ARM microprocessor-TM4C123GH6PGE is used as the cybernetic core of the control system. To improve the response performance and reliability of the power system, close-loop control and peak current feedback control modes are adopted. In the end, the experimental study of the performance testing and cutting of the developed prototype is carried out. The results indicate that the design is rational and feasible, and the developed high power plnsma cutting power supply works reliably with excellent performance.     

可视化人机交互系统的研制

针对数字化焊接电源人机交互需求,研制了一款可视化的人机交互系统。以基于Cortex-M3内核的ARM微处理器LM3S9B96为主控制器,以17.78 cm(7英寸)触摸显示屏AT070TN92为可视化人机交互的媒介,采用双图层TFT-LCD控制芯片RA8875作为液晶驱动器,实现了所有焊接参数的输入和过程状态信息的实时显示;开发了SD卡接口,实现了数据的可靠存储;设计了多种标准的通信接口电路,确保人机交互系统具备良好的可移植性和可扩展性。整个系统的人机界面友好,操作简单,稳定可靠。     

Underwater robot local dry welding system

To satisfy the demand for good quality underwater welding and maintenance of nuclear power stations, a set of local dry automatic welding systems has been developed. These systems were based on an underwater robot that consisted of a special high-power underwater welding power supply, diving wire feeder, mini drain cap, welding robot, and special underwater welding torch. With a digital signal controller microprocessor as its core and combined with a dual inverter topology, the welding power supply was characterized by full-digital construction and multi-waveform flexible output. A compact diving wire feeding device was designed, based on the armature voltage negative feedback and high-frequency chopping pulse width modulation.This device yielded a high-efficiency seal of the driving motor with the help of dynamic and static sealing technology. To overcome the difficulty of local protection and deslagging in the welding area, a mini drain cap (with a duplexgas structure) based on the principle of the convergent nozzle was designed. The practical tests and the underwater welding experiments revealed that the underwater robotic local dry welding system is quite feasible. That is, the system could strike the arc stably and reliably in the shallow water environment, and formed beautiful welding seams.     

基于ARM的全数字多功能方波逆变焊机

研制了一种基于ARM(advanced RISC machines)全数字多功能方波逆变焊机,主电路采用双逆变结构,前级逆变电路选用全桥拓扑,后级逆变电路采用双半桥并联结构;以基于Cortex-M3内核的LM3S8971 ARM微处理器为核心,设计了焊接过程数字化控制系统;通过电流闭环控制和数字PID调节,实现前级逆变电路的恒流特性输出,同时对后级逆变电路进行数字化低频调制,获得多种电流波形输出;设计了基于ARM+CPLD双芯结构的数字化面板,实现了人机交互的数字化.结果表明,研制的多功能逆变焊机动态性能好、控制灵活、操作便利、设计合理可行.     

水下弧焊机器人焊丝状态检测技术的研究

针对水下焊接机器人自动化焊接需求,研制了一种基于电涡流式接近开关的非接触式焊丝状态检测装置,实现了焊丝状态的非接触、实时监测。以ARM微处理器STM32F405RGT6和NPN常闭型电涡流式接近开关TCO-3040BL为核心,设计了完善的数字化检测电路;采用算数平均滤波算法和限幅滤波算法来提高采样精度和抗干扰能力。试验结果表明,该装置反应灵敏,检测耗时少于4 ms,检测端电压波动小,结果稳定、可靠,适应性强,能满足水下弧焊机器人实际应用要求。     

电力电站冷凝器钛合金管板自动焊机的研制

为提高电力电站冷凝器钛合金管板接头环形焊缝的焊接质量,研制了一种数字化、可视化以及自动化的管板焊机.为提高动态响应性能,焊接电源主电路采用了逆变频率为100 kHz的全桥拓扑结构;以基于ARM公司Cortex-M4内核的LM4F232 MCU(微控制器)为核心,设计了焊接过程数字控制系统,开发了基于模糊逻辑判断的参数自整定PI(比例积分)算法,提高了焊机对不同工况的适应性;设计了基于触摸屏和ARM微处理器的人机交互系统,实现了人机交互的数字化和可视化.系统测试以及焊接试验均表明,研制的管板焊机性能优良,能够满足冷凝器钛合金管板优质高效焊接的需求.     

水下机器人局部干法焊接系统的分析

针对核电站优质水下焊接修复需求,研制了一套局部干法水下机器人焊接系统.以DSC微处理器为核心,结合二次逆变主电路,设计了全数字多波形柔性输出的大功率水下焊接电源;采用电枢电压反馈控制、高频斩波脉宽调制及动静密封技术,开发了紧凑型潜水送丝装置;针对焊接局部保护和排渣难题,开发了基于收缩喷管原理的双气帘结构微型排水罩.集成专用水下焊枪、机器人、视觉系统等,搭建水下机器人局部干法焊接试验平台,开展水下焊接试验.结果表明,研制的局部干法焊接系统样机性能可靠,引弧成功率高,焊接过程稳定,焊缝成形美观.