| 2026 №05 (09) |
DOI of Article 10.37434/as2026.05.01 |
2026 №05 (02) |
"Avtomatychne Zvaryuvannya" (Automatic Welding), #5, 2026, pp. 3-9
Optimization of the pulsed current waveform and parameters in HFPC TIG welding
I.V. Krivtsun1
, V.F. Demchenko1, D.A. Nomirovskii2, O. Mokrov3, D.V. Kovalenko1
1E.O. Paton Electric Welding Institute of the NAS of Ukraine
11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.
Е-mail: d_v_kovalenko@ukr.net
2Taras Shevchenko National University of Kyiv. 60 Volodymyrska Str., 01033 Kyiv, Ukraine
3RWTH Aachen University, ISF – Welding and Joining Institute Pontstr. 49, 52062 Aachen, Germany
Experimental studies have shown that high frequency pulsed modulation of welding current allows for an increase in penetration capacity of the welding process with refractory cathode. This effect is attributed to intensified convective flows in the weld pool, excited by the force action of a high-frequency electromagnetic field. The article examines the problem of determining the shape and parameters of welding current pulses that maximize the force exerted by the modulated current on the weld pool metal. The square of the effective value of the welding current is taken as an integral measure of the force action of the electromagnetic field on the molten metal of the weld pool. The difference between the squares of the effective and average values of the modulated current, which characterizes the excess of the force action of the arc with pulsed current modulation over the force action of the direct current arc, is taken as a criterion for optimizing the shape of the current pulse. The problem of variational calculus on finding such a current pulse shape, at which the maximum of the specified difference is achieved, is solved. Two optimization methods are considered: at a given modulation amplitude and at a given average value of the modulated current. It is rigorously shown mathematically that in the first case the optimal pulse shape is a square wave, in the second case it is a rectangular current pulse, the duty cycle and amplitude of which are determined by the value of the maximum current of the welding generator. The optimization of parameters of current pulses of trapezoidal and triangular shapes generated by existing welding current generators has been carried out. The proposed theory can serve as a guideline in the development of effective pulse current generators, as well as in the design of the modes of the tungsten inert gas welding process with high-frequency pulsed modulation of welding current, in order to increase the penetration depth and improve welding productivity. 12 Ref., 2 Tabl., 4 Fig.
Keywords: TIG welding, arc plasma, weld pool, electromagnetic force, direct current, pulsed current, mean and RMS values, wave form, duty cycle, amplitude, frequency
Received: 17.12.2025
Received in revised form: 03.02.2026
Accepted: 30.09.2026
Posted online: 20.10.2026
References
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This article is licensed under a Creative Commons Attribution Non-Commercial 4.0 International (CC-BY-NC).
Suggested Citation
I.V. Krivtsun, V.F. Demchenko, D.A. Nomirovskii, O. Mokrov, D.V. Kovalenko (2026) Optimization of the pulsed current waveform and parameters in HFPC TIG welding. Automatic Welding, 05, 3-9. https://doi.org/10.37434/as2026.05.01Advertising in this issue:
