等离子体控制是解决高功率激光焊接的关键技术。为完善对等离子体控制技术 ,对焊接过程中等离子体电流的形成进行了理论分析 ,并将等离子体导电过程简化等效为一个具有内阻的电源模型。采用 3 k W CO2 激光器在不同激光焊接规范下 ,依据测量得到的等离子体电流计算得到了等效电源电压和等效内阻。最后依据此模型成功实现了辅助磁场对等离子体的控制 Plasma control is to solve the key technology of high-power laser welding. In order to perfect the plasma control technology, the formation of plasma current during welding was theoretically analyzed, and the plasma conduction process was simplified as a power model with internal resistance. Using 3 k W CO2 laser under different laser welding specifications, the equivalent power supply voltage and equivalent internal resistance were calculated based on the measured plasma current. Finally, based on this model, the control of the plasma by the auxiliary magnetic field is successfully achieved