Research Of The ARC Welding Power Supply System With Presetting And Controlling Parameters

The system of welding parameters presetting and controlling is, presetting welding current, welding voltage and other parameters according to the corresponding welding carft before welding, in the welding process,using appropriate software to adjust the output of arc welding power source, making sure that the real-time welding parameters and the preset parameters keep consistent. In allusion to the control features of automatic arc welder and the requirements of welding processes, the arc welding power supply system with presetting parameters which with PIC24FJ64GA002 as the control core and supplemented by external circuit was designed in this paper. Peripheral circuits include power supply circuit of digital of analog circuit, sampled signal isolated circuit of welding current and voltage, the circuit of D/A conversion and signal output, the circuit of parameter display and adjust, the microcontroller reset circuit and the signal conversion circuit.And the paper is detailed the work process of sampled signal isolated circuit of welding current and voltage, the circuit of D/A conversion and signal output and the circuit of parameter display and adjust, tested the sampled signal isolated circuit of welding current and voltage, checked the linearity of optical isolation circuit to ensure the accuracy of the input signal.To ensure the preset and control parameters system can work smoothly, there not only needs the hardware, but also needs the software programs which make the hardwares operation under the requirement. So, this paper uses C language to programming to realize that the acquisition of the welding current/voltage parameters, parameters conversion process, displaying parameters in real time and adjusting parameters at any time, PID algorithm controlling,the use of microcontroller PWM to achieve D/A conversion. There are the details of software programs for each module, and corresponding experiments were done to ensure the normal function of each module. For achiveing the best control precision, the method of critical ratio was used to dertermine the PID algorithm controlling parameters which was fine-tuned based on the actual control process. Furthermore,to assure the stability and accuracy of the control system, it was designed a variety of software and hardware protective measures so as to improve the anti-interference abilities of this system.Finally, the preset and control parameters system was debugged based on arc welding power source. It was proved that the acquisition, real-time display and real-time adjustment for the welding parameters, achieved the purpose of the parameters presetting, had a good general, and should continue to develop applications.