Electrical Characteristics of Low-Voltage AC Series Arcs According to Load Current Under Linear Load Conditions
Year: 2026
Type: article
Abstract: The electrical characteristics of low-voltage AC series arcs according to the load current (1, 3, and 5 A) were investigated under linear load conditions. A current waveform analysis identified nonlinear distortion, particularly the shoulder effect near zero-crossing regions. Frequency domain analyses using fast Fourier transform and total harmonic distortion (THD) demonstrated that harmonic current components are primarily concentrated in the low-frequency range below 3 kHz, where cumulative THD values saturate. As the load current increased, the THD delta between normal and arc conditions expanded from 1.526% to 2.084%, reflecting intensified nonlinearity. A detailed harmonic analysis revealed that the ninth harmonic maintains a consistent level deviation of approximately 15 dB, regardless of the current magnitude, serving as a robust indicator. Furthermore, the odd/even harmonic root mean square current ratio increased by up to 153.3% at 5 A, exhibiting a distinct feature for arc discrimination. This phenomenon is driven by the enhanced generation of odd harmonics and the sustained suppression of even harmonics owing to half-wave symmetry. In this research, the harmonic characteristics were quantified based on the load current, and the critical factors for effective arc fault discrimination in linear load environments were identified.
Source: Fire science and engineering
Authors: Wanguen Ji, Sunghwan Kim
Institutions: Inha University, Jeonju University
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W7160039834