| The digital technology has rather superiority.The development of accuracy control and flexible automation of inverter welding power source are promoted by it,which overcome drawback of analog technology.It is said that digital technology is developmental trend of inverter welding power source.This paper introduces the concept of digitalization firstly,then analyzes the characteristics of digital inverter welding power source.According to the research trend at homeland and overseas,it is very necessary to research.The give birth to,application field and development trend of DSP are introduced briefly and its work principle,structure characteristics and select are explained in detail.This paper emphasizes on the component parts and control principle of digitalized IGBT inverter MMA/TIG wave welding power source.Main circuit,control circuit,protection circuit,drive circuit and the equipment of high frequence arc starter are respectively analyzed.The software and hardware are also interpreted.Main circuit,which applies IGBT full-bridge inverter structure,is made up of input rectifier,filter,high-frequency transformer and output rectifier circuit.The key points and the parameters of design,select of parts of apparatus are discussed particularly.High performance 16-bit DSP TMS320LF2407A is adopted as control kernel.Using universal PWM method means to control output power and output characteristic through controlling IGBT switch on time.Because TMS320LF2407 can directly generate requisite pulse waveform with dead-band. The separate two pulses trigger IGBT after they are magnified by exclusive drive module M57959L.The system samples output current in real time and bring it to DSP for A/D conversion.This paper also expound the resource distribution and the function of outer circuits.Aim to typical problems in welding process:over voltage,lack voltage,over current and over heat, a corresponding protection circuit is designed.In order to overcome the high frequency interference of high arc starter to DSP control system,the corresponding arc starter control circuit is designed,which improves the stability of the power.The installation and setup of DSP develop environment CCS2000 and using of develop tool 5100USB are illuminated.Under the exploder environment,adopt assemble language,design system software by modularize methods.The frame and function of main program,interrupt service subroutine and devises function subroutine are explained.too.Transit experiment,analyse scheme and constitute of the power,gained the primary experiment results.Corresponding data and waveforms are recorded in the experiment,and problems occurred in experiment are investigated and lodge resolvents.The experiment results show that main circuit of the inverter power source has rapid response-speed,hardware has high reliability and simpleness,software has high effect,fine transplant and strong ability of anti-jamming.The inverter power source basicly achieved the compose and require of initially design.At last,some advices on future research for the welding power are given,and they will make a found ground for tomorrow's research of digital welding power.
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