Variable-polarity arc welding power source and its control method

Abstract

The invention provides a variable polarity arc welding power source and a control method thereof, belonging to the field of welding technology. The polarity-changing arc welding power supply includes: welding current setting unit, current detection unit, controller and inverter power supply circuit; welding current setting unit, current detection unit and inverter power supply circuit are electrically connected to the controller respectively, and the welding current setting unit The setting unit is used to set the ideal welding current, and the current detection unit is used to detect the actual welding current. The controller includes: a polarity judging unit, used to judge the polarity of the control stage according to the actual welding current detected by the current detection unit; The actual welding current is used to control the output welding current of the inverter power circuit. The invention can adopt different control parameters to control according to different polarity control stages, effectively solves the problem that the two polarity waveforms cannot be taken into account when the parameters are fixed, and realizes precise control of variable polarity arc welding.

Description

[technical field] [0001] The invention relates to the field of welding technology, in particular to a variable polarity arc welding power source and a control method thereof. [Background technique] [0002] Variable polarity arc welding is widely used in the welding process of aluminum and aluminum alloys. Variable polarity arc welding includes AC tungsten argon arc welding (TIG) and so on. For the variable polarity arc welding power supply, when the positive half-wave control is applied to the electrode, the positive voltage is applied to the electrode, the base metal is negative, and the current flows from the electrode to the base metal; when the negative half-wave control is applied, the positive voltage is applied to the base metal, the electrode is negative, and the current Flow from the base metal to the electrode. Due to the large difference between the discharge ability of the variable polarity arc welding electrode to the base metal and the discharge capacity of ...

AI Technical Summary

Problems solved by technology

Due to the large difference between the discharge ability of the variable polarity arc welding electrode to the base metal and the discharge capacity of the base metal to the electrode, it is difficult to achieve consistent control of the positive and negative half waves of the variable polarity arc welding during polarity variable welding, so that it cannot be realized The stable arc performance of variable polarity welding can easily lead to serious welding burnout, unstable welding arc, poor weld formation, and spatter in welding

[0003] At present, the variable polarity arc welding power supply is controlled by fixed control parameters, and the difference between the discharge capacity of the electrode to the base metal and the discharge capacity of the base metal to the electrode is not considered in the control. Therefore, the above-mentioned shortcomings are common.

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