Design Of Inverter Arc Welding Power Supply Based On DSP

The inverter arc welders have many advantages such as small volume, light weight, high efficiency and flexible control capability. The digital control technique, particularly the availability of the high speed digital signal processor (DSP), enhanced the performance of the inverter arc welders. The features are attractive and draw great attention from wide range of engineers and researchers.The thesis presents an inverter welder of 4.5KVA, mainly focuses on power circuit design and digital control implement.The main circuit is based on AC-DC-AC-DC conversion to achieve high efficiency, stable arc, high density power conversion and low noise. For high conversion frequency, the force-commutated power switch of IGBT is used; for high efficiency no-crystal ferromagnetic material is used as the inverter transformer for reducing the ferromagnetic losses.Without the control circuit, the main circuit can't work. And the control circuit is around a TMS320LF2407 DSP. The A/D conversion, the PID control method and PWM signal generation built in the DSP chip is well utilized, to form closed loop feedback control. Meanwhile, the PID controller is simulated and programmed to stabilize the arc current as the setting value.Finally, the test model is implemented, the experimental verification shows that the model is of high performance and has the features of flexible control, convenient debugging, high reliability, and worth to develop for manufacturing.