大功率双丝脉冲MIG焊双电弧干扰形成机理及双脉冲群智能优化策略

High power twin-wire pulsed MIG welding process is an effective solution to get the production efficiency increased significantly and one of the efficient welding methods. However the serious interference of twin-arc, which is caused by high-current, makes the welding process unstable and has become the prominent problems for the application of this technology. High-current twin-arc is chosen as the study object, and a thorough research on the interference law, modeling, simulation and optimization of twin-arc characterized by multi-physics coupling is presented.Firstly, theoretic analysis and calculation of multi-physics coupling character equation on electric field, magnetic and flow field of twin-arc are presented, and the shapes, movement characteristics and interaction of twin-arc are studied. Secondly, a waveform control of dual pulse is proposed to reduce the interference of twin-arc, and the dynamic and numerical simulation model of dual-pulse twin-arc is established. Finally, to aim at the character of multi-parameters of dual pulse, the numerical simulation is carried out combining with experimental investigation and a particle swarm intelligence optimization strategy is developed, which takes the interaction force as the objective function. The multi-parameters optimization of twin-arc based on dual pulse and the model for quantitative prediction of twin-arc interference based on dual pulse are developed. The project is to reveale the interference law of high-current twin-arc and to realize the optimization control of twin-arc interference based on dual pulse, and has the significance on the reduction of twin-arc interference and the improvement of high power twin-wire pulsed MIG welding system, and provides scientific basis for the design and engineering application of high power twin-wire pulsed MIG welding system.

大功率双丝脉冲MIG焊是提高焊接生产效率的有效途径，是高效化焊接的实现方法之一，然而大电流引起双电弧干扰严重，使焊接过程不稳定，成为制约其推广应用的主要瓶颈。本项目以大电流双电弧为研究对象，对以多物理场耦合为特征的双电弧干扰规律、建模、模拟和优化进行体系研究。首先理论分析和计算双电弧的电场、磁场和流场多物理场耦合特征方程组，对双电弧的形态、运动规律及相互作用规律进行研究；其次提出双脉冲波控减小双电弧相互干扰，建立双脉冲双电弧作用力的动力学数值模拟模型；最后针对双脉冲参数多的特点，应用粒子群群智能优化策略，以双电弧相互作用力为目标函数，结合工艺试验进行数值模拟，实现双电弧双脉冲多参数优化，建立基于双脉冲的双电弧干扰定量预测模型。本项目旨在揭示大电流双电弧干扰规律和实现双电弧干扰双脉冲优化控制，对减小双电弧干扰和完善大功率双丝脉冲MIG焊系统具有重要意义，可为其设计和工程化应用提供科学依据。

大功率双丝脉冲MIG焊是提高焊接生产效率的有效途径，是高效化焊接的实现方法之一，然而大电流引起双电弧干扰严重，使焊接过程不稳定，成为制约其推广应用的主要瓶颈。本项目以大电流双电弧为研究对象，对以多物理场耦合为特征的双电弧干扰规律、建模、模拟和优化进行体系研究。首先理论分析和计算双电弧的电场、磁场和流场多物理场耦合特征方程组，对双电弧的形态、运动规律及相互作用规律进行研究；其次提出双脉冲波控减小双电弧相互干扰，建立双脉冲双电弧作用力的动力学数值模拟模型；最后针对双脉冲参数多的特点，应用粒子群群智能优化策略，以双电弧相互作用力为目标函数，结合工艺试验进行数值模拟，实现双电弧双脉冲多参数优化，建立基于双脉冲的双电弧干扰定量预测模型。. 在分析双丝脉冲MIG焊原理和特征的基础上，确定了大功率双丝脉冲MIG焊电源系统总体技术方案。分析了逆变式焊接电源主电路拓扑结构，根据大功率双丝脉冲MIG焊电源输出大功率化的要求，焊接电源选用全桥逆变主电路并联拓扑结构。分析了双电弧干扰的产生原理，并针对双电弧干扰，确定了减小双电弧干扰的脉冲焊接方法和双脉冲群优化方案。. 对所研制的大功率双丝脉冲MIG焊系统进行模拟负载试验和大功率双丝脉冲MIG焊工艺试验。试验结果表明，所研制的大功率双丝脉冲MIG焊系统满足设计要求，实现了同步、交替和随机三种相位的单脉冲和双脉冲焊接，焊接效率高，双脉冲优化焊接能改善焊缝成形质量。对大功率双丝脉冲MIG焊双电弧进行高速摄像研究，通过拍摄的双电弧形态图像分析了单脉冲和双脉冲焊接工艺下的双电弧干扰情况，试验结果表明，采用脉冲焊的交替相位焊接工艺，能有效减小双电弧干扰；对于同步相位焊接方式，通过采用双脉冲优化焊接工艺，则能优化双电弧之间电弧力的分布情况，减小双电弧的相互干扰。. 本项目旨在揭示大电流双电弧干扰规律和实现双电弧干扰双脉冲优化控制，对减小双电弧干扰和完善大功率双丝脉冲MIG焊系统具有重要意义，可为其设计和工程化应用提供科学依据。