Research On Integrated And High Power Factor Arc-welding Inverter Power Supply

As a major21st century manufacturing processing technology, welding becomes veryimportant in the national economy. Uncontrolled diode-rectifiers are usually adopted as theprimary stage of general arc welding inverter supply，These circuits are lead to the inputcurrent distorts seriously，so we need to take measures to eliminate harmonics and dopower factor correction. At the mean while, they will reduce the power factor of weldingsupply, increase the demand of supply power capacity. With the implementation ofinternational standards related to harmonics, arc welding power source must be resolvedharmonic pollution in order to make a breakthrough in China’s weldingindustry. High-frequency PWM rectifier can provide low harmonic sinusoidal input current,power factor can be adjusted to solve the conventional rectifier to the power grid caused bypollution, so we choose three-phase voltage source inverter welding rectifier as the inputrectifier to solve the current harmonics and power factor problems.This paper introduces the principle of voltage-source PWM Rectifier, selectsthree-phase voltage-controlled inverter as the main circuit, and establishes mathematicalmodels of three-phase inverter. Describes the static characteristics of the rectifier andoperating range of the mathematical description.Clarify the carrier pulse-width modulationand space vector modulation of the relationship, that the carrier injection pulse widthmodulation based on the zero-sequence component can be equivalent to the space vectormodulation, space vector modulation can improve the utilization of the DC voltage. Studiedthe double closed loop control method of three phase voltage type PWM rectifier based onSVPWM, and use simulation to verify the theoretical analysis is correct. Designed athree-phase voltage-type PWM rectifier of the main circuit parameters, the calculation ofthe engineering parameters of the dual closed-loop controller, vector modulation currentcontrol mode makes the rectifier has a good dynamic characteristics. To meet the load arcwelding power source characteristics, the load current feed-forward options for resolvingthe mutation load output voltage of DC side impact problem. In addition, the arc weldingpower supply device for an integrated simulation of the control scheme used in thefeasibility to achieve high power factor, low current harmonics to meet the relevantstandards. Pre-built prototype high frequency rectifier experiment, combined with the existinginverter arc welding power supply to carry out experiments. The results validate thefunction of three-phase voltage-type rectifier, inverter welding power source prototypeof good performance, to meet the relevant standards.