Study On Novel Half-bridge Soft-switching Inverter Arc Welding Power Source

Inverter arc welding power source is a kind of welding equipment that transformsAC from the power grid into low-voltage and large-current DC with the aid of powerelectronics PWM converter circuit. As new generation of power devices, soft-switching circuit topologies, digital control and intelligent control technologies aredeveloping, inverter arc welding power source has been further improved in highefficiency and energy saving, light weight, integrated, real-time control, consistencyand reliability.This paper utilizes the new full-control type power device, the soft-switchingtechnology, digital intelligent control and other advanced technologies for design andresearch of a new inverter arc welding power source. Base on comparative analysis ofthe converter topology and work principle of traditional inverter arc welding powersource, a novel half-bridge soft-switching DC-DC converter topology of the inverterarc welding power source is studied in this paper. The innovative aspects of this paperis the research of novel half-bridge soft-switching DC-DC converter topology andvoltage Fuzzy-PI compound controller. Switching frequency of the novel half-bridgesoft-switching DC-DC converter is greatly improved and the welding performance iseffectively ameliorated. In order to meet the optimal control requirements of thestrong nonlinear and time-varying inverter arc welding power source, a kind ofvoltage Fuzzy-PI compound controller whose parameters achieve on-line real-timeadaptive tuning to realize the optimal control of inverter arc welding power source isdesigned based on peak-current mode of double closed-loop control system.In order to verify the feasibility and correctness of the novel half-bridge soft-switching inverter arc welding power source and to analyze the relationship betweenthe physical quantities and power devices switching performance of the new half-bridge soft-switching DC-DC converter, a novel half-bridge soft-switching DC-DCconverter inverter arc welding power source Matlab simulation model with fuzzy-PIcompound control double closed-loop control system is established in this paper.Themain circuit and control circuit of the novel half-bridge soft-switching inverter arcwelding power source is optimally designed. The main circuit design is focused onrealizing soft-switching work, at the same time, the selection and parametercalculation of power switch IGBT, high frequency transformer, high frequency rectifier diodes and other main components. The design of control circuit hardwarecircuit includes DSP control unit based on dsPIC30F6010A, voltage and currentsampling circuit, IGBT drive circuit and protection circuit. The design of controlsoftware program utilizes C language and assembly language mixed programming inthe DSP integrated development environment provided by Microchip. Finally, theexperimental prototype platform is developed for experimental study, experimentalresults verify that the novel half-bridge soft-swithing inverter arc welding powersource can effectively overcome the lack of traditional hard-switching inverter arcwelding power source like large switching losses and achieve flexible, intelligent anddigital control of inverter arc welding power source. The novel half-bridge soft-switching inverter arc welding power source that has obvious advantages such as lowenergy loss and high welding process quality is further demonstrated through thestudy of this paper, which has a good prospect of application.