Digital AC servo push & pull feeding system for CO₂ welding

A push pull feeding system with real-time control for CO₂ welding was proposed and achieved.It utilizes the motion controller to control AC servo motor with the low moment of inertia, fast response, and the buffer to connect the constant feeding part and the push & pull feeding part.The PWM feeder speed control circuit with speed negative feedback by rotate coder was designed to compensate the speed fluctuation caused by the system load and supply voltage changing.The push & puller feeding mechanism was designed to push pull the wire based on the AC servo motor.According to the characteristics of CO₂ welding with push & pull feeding system, the feeder speed curve is pre-designed.The wire motion was managed by the real-time control software written in the motion controller.The system has good ability in anti-jamming and stability.The highest feeder frequency with push & pull process can reach 90 Hz.