# ANALYSIS OF THE STABILITY OF THE ELECTRICAL POWER SUPPLY SYSTEM OF THE WELDING ELECTRIC AND PLASMA ARC

## Keywords:

stability, power supply system, electric arc, the arc inertia

## Abstract

Purpose. Consideration of issues related to the stability problem of the "power source - electric arc" system with small disturbances and its solution in the framework of the method of small oscillations. Discussion of the choice of a mathematical model, the presentation of an effective approach to solving stability problems, based on the use of general equations of quasistationary modes for the analytical description of AC circuits.

Methodology. In methodological terms, the article is based on the well-known classical principles of the general theory of stability. Basically, stability under small perturbations is considered and methods are used that are based on the analysis of differential equations of the first (linear) approximation, which have received fruitful application and development in the theory of automatic control.

Findings. Examples of solving specific problems of stability in analytical, as well as in graphic or graphoanalytic form, are important in the formation and approval of theoretical principles. Unlike numerical solutions, they illustrate more clearly all the characteristic aspects of the problem. In particular, they are a good illustration of the distinctive side of the aperiodic stability problem that its solution depends solely on the static characteristics of the system elements and can be obtained within the framework of only finite equations, and the resistance coefficient can be used as a stability criterion.

Originality. The well-known method was further developed in relation to a new object of study - a soft-switching converter operating on an electric arc. Special attention has been paid to a clearer formulation of the problem and a more differentiated assessment of its acceptability for the given technical system.

Practical value. In connection with the continuous development of individual power supply systems, the importance of the problem of their sustainable operation is growing even more. The article can serve as a real basis for a constructive solution to the problems of the general theory of stability of new power supplies for technological loads, contribute to the creation of favorable conditions for its further fruitful development, as well as for the development of new effective methods for solving specific problems of interest to specialists in the field of power supply systems of electrotechnological installations.

## Author Biographies

### YE.M. Vereshchaho, Admiral Makarov National University of Shipbuilding

PhD in technical sciences, associate professor, associate professor of the Marine Instrument Department of the Admiral Makarov National University of Shipbuilding, Mykolayiv

### V.I. Kostiuchenko, Admiral Makarov National University of Shipbuilding

PhD in technical sciences, associate professor of the Marine Electric Power Systems Department of the Admiral Makarov National University of Shipbuilding, Mykolayiv

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2019-10-01

## How to Cite

Vereshchaho, Y., & Kostiuchenko, V. (2019). ANALYSIS OF THE STABILITY OF THE ELECTRICAL POWER SUPPLY SYSTEM OF THE WELDING ELECTRIC AND PLASMA ARC. Electrical Engineering and Power Engineering, (3), 34–41. https://doi.org/10.15588/1607-6761-2019-3-4

Electrotechnics