动力电池焊接熔深在线监测与闭环控制

On-line monitoring and closed-loop control of power battery welding depth

摘要: 采用光学相干层析(OCT)对焊接熔深进行在线监测,研究了OCT监测技术的稳定性及焦距自适应性.结果表明:O C T监测的熔深结果与金相结果吻合度高,其误差不超过3.65%.O C T技术对焊接工况的变化不敏感,随着焊接功率、焊接速度及保护气流量的变化,O C T监测的熔深结果误差稳定在0.24%～3.65%之间.在±2.5mm的波动范围内,不同高度焊件OCT监测的熔深标准差仅0.072mm,其过程能力指数CMK达3.51.由此证明,OCT熔深监测技术具有优异的抗干扰能力及焦距自适应性,可以实现对焊接熔深的闭环控制.

Abstract: Optical coherence tomography(OCT)was used to monitor the welding depth on line.The stability and focal length adaptability of OCT were studied.The results show that the depth results of OCT are in good agreement with the metallographic results,and the error is less than 3.65%.OCT technology is not sensitive to the change of welding conditions.With the change of welding power,welding speed and protection gas flow,the error of OCT depth results is stable between 0.24%and 3.65%.Within the fluctuation range of±2.5mm,the standard deviation of OCT depth results of different height welded parts is only 0.072mm,and the process capability index CMK is 3.51.The results show that OCT depth monitoring has excellent anti-interference ability and focal length adaptability,and can realize closed-loop control of welding depth.