| The combination of inverter technology and soft-switching technology makes the welding power to carry out high frequency, light weight and big capacity. But the adoption of the digital signal processor(DSP) makes power supply really to head into numeral, makes the anti- interference ability of the power supply, compute ability, real-time ability and integrated level to get an improvement to a large extent. The main purpose of this paper lies in researching a numeral soft-switching welding inverter based on DSP.This paper firstly introduces the development history, actuality about the arc- welding inverter and forecasts the foreground and trend of it. In the meantime, we discuss the characteristics of welding power supply, and then we give the design ideas of numeral welding power, introduce the design methods of main circuit and control circuit of it in detail. A full-bridge configuration which cooperates with high frequency transformer and commutator is used to be main circuit, and IGBT is the primary switch component. The leading leg achieves ZVS, and the lagging leg is ZCS by the combination of soft-switching and inverter technology, which gets over the drawback of FB-ZVS-PWM circuit. The run-state of main circuit is analysed. The parameters of transformer and resonant components are calculated. The input and output rectifier is designed. We take UC3879 as the core of PWM controlling to carry out soft-switching and TMS320LF2407A as the core of all controlling system. The peripheral circuits are given in the paper. These circuits include the microprocessor circuit, the circuit used to give parameters and to show them, the PWM circuit and the safeguard circuit. The control strategy adopts Fuzzy-PID control, it's design method is shown in the paper.For the main circuit and control circuit in the paper, we construct the simulated model through Matlab/Simulink tools, and give the simulated waves. In order to protect the reliability of the system, we used many anti-jamming measures.
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