Fast-frequency pulse TIG welding system

Abstract

The invention provides a fast-frequency pulse TIG welding system. The welding system is characterized in that the system comprises a fast-frequency pulse TIG welding power source; the fast-frequency pulse TIG welding power source comprises a main circuit, a control circuit and a human-computer interaction system; the main circuit comprises a power frequency rectification filtration module, a pulsecurrent main circuit, a base value current main circuit and a high-frequency current switching circuit; the pulse current main circuit comprises a SiC full-bridge current inverting converting moduleI, a high-frequency voltage transformation module I and a SiC rectification smoothing module I, wherein the SiC full-bridge current inverting converting module I, the high-frequency voltage transformation module I and the SiC rectification smoothing module I are sequentially connected; the base value current main circuit comprises a SiC full-bridge current inverting converting module II, a high-frequency voltage transformation module II and a SiC rectification smoothing module II, wherein the SiC full-bridge current inverting converting module II, the high-frequency voltage transformation module II and the SiC rectification smoothing module II are sequentially connected; the high-frequency current switching circuit comprises a high-frequency switching module and an anti-backward-pouring module which are connected in sequence; and the SiC full-bridge current inverting converting module I comprises a SiC power switch tube. The welding system is high in inversion frequency, good in dynamic characteristic and stability, and can reduce the power tube switch loss.

Description

technical field [0001] The invention relates to the technical field of welding equipment, and more specifically, relates to a fast-frequency pulse TIG welding system. Background technique [0002] In the field of welding, tungsten argon arc welding (TIG welding for short) has been widely used for its advantages of stable arc, zero spatter, high welding quality and wide range of weldable metals. Pulse TIG welding technology, which began in the mid-1960s, superimposes pulse current with a certain frequency on the basis of traditional DC arc welding. The peak current can keep the arc stable and accelerate the melting of the base metal to form a molten pool, while the base current It can control the input of heat and maintain the continuous burning of the arc, so that the molten pool is cooled and crystallized, and the two cycle alternately to form a weld with good performance. At present, the high-frequency pulse TIG shrinks the arc through the electromagnetic field generated ...

AI Technical Summary

Problems solved by technology

However, there is still a large gap between the industrialization level of domestic fast-frequency pulse TIG welding equipment and developed countries. Welding power supplies generally use Si-based IGBTs as the main device for power conversion, while the switching performance of traditional Si-based power devices has been reduced. It is close to the theoretical limit determined by its material properties, which to a certain extent restricts several key indicators in the welding power source that affect the reliability of fast-frequency pulse TIG welding, such as inverter frequency and response speed, making the overall size too large and the dynamic characteristics insufficient. good

In addition, due to the addition of high-frequency current modulation, the fast-frequency pulse TIG welding technology will generate strong electromagnetic interference to the welding power source, which is prone to problems such as unstable welding current and poor arc control effect in high-frequency bands.

Therefore, fast frequency pulse TIG welding technology has not been widely used in China

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