High impedance fault detection method for distribution networks under non-linear conditions

• Published in: International journal of electrical power & energy systems Vol. 131; p. 107041
• Main Authors: Lima, Érica Mangueira, Coelho, Rodrigo de Almeida, Brito, Núbia Silva Dantas, Souza, Benemar Alencar de
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.10.2021
• Subjects: Distribution networks; Harmonics; High impedance faults; Non-linear loads; Stockwell transform; Harmonics; Stockwell transform; Non-linear loads; High impedance faults; Distribution networks
• ISSN: 0142-0615; 1879-3517
• DOI: 10.1016/j.ijepes.2021.107041

•New HIF method for distribution networks with the presence of non-linear loads.•Online monitoring of 3rd harmonic phase angle sample-by-sample for fault detection.•Requires only a single measurement point on the substation.•Detection method not affected by system characteristics or fault location.•Overall detection rate of 99.32%, with no false positives. This paper presents a new high impedance fault (HIF) detection method considering the presence of non-linear loads in the distribution network. It adopts a cumulative error-based index to monitor the third harmonic phase angle, which is extracted with Stockwell transform and compared to a self-adaptive threshold for fault detection and classification. The proposed method requires only a single measurement device on the substation. Results show that the proposed method is able to quickly detect HIF in all simulated cases, considering several fault locations and different contact surfaces, not being affected by conditions such as fault inception angle, system loading percentage, or fault location. Additionally, results suggest that it can distinguish HIF from capacitor banks switching, low impedance faults, transformer energizing, and feeder energizing along with linear and non-linear loads switching. HIF real oscillographic records are also used for validation. The proposed method achieved a fast detection, in less than 11 cycles for most cases, and a high detection rate, over 99%, with no false positives.