Volume 18, Issue 4 (December 2022)                   IJEEE 2022, 18(4): 85-97 | Back to browse issues page

XML Print

Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:
Alizadeh Shyrayeh H, Ahmadi I, Mirzaie M, Ahmadi gorji M. Reliability Assessment of Distribution Transformers Considering Load Harmonics. IJEEE 2022; 18 (4) :85-97
URL: http://ijeee.iust.ac.ir/article-1-2534-en.html
Reliability Assessment of Distribution Transformers Considering Load Harmonics
Hassan Alizadeh Shyrayeh , Iraj Ahmadi , Mohammad Mirzaie , Masoud Ahmadi gorji
Abstract:   (1067 Views)
The progressive application of non-linear loads in distribution systems (DS) increases current harmonics flow in DS's apparatuses, especially distribution transformers (DTs). Since DTs' operating temperature rises due to the harmonics flow, their loading should be reduced such that the hot spot temperature (HST) is preserved under its permissible value. This means that DTs' available capacity is influenced by load harmonic content. In this paper, a novel formulation for DTs' failure rate in the presence of harmonics is presented as a function of load harmonic contents. Using the suggested equivalent failure rate, DTs' available capacity in harmonic polluted DS is mathematically formulated. Additionally, the presence of the harmonic increases the HST, leading to DTs' aging acceleration. Therefore, the impact of harmonic components on DTs' aging is arithmetically modeled. To evaluate the efficacy of the suggested reliability model, it is applied to three distinct DTs having respectively industrial, commercial, and residential loads. The obtained results indicate that the available capacity of DTs with the same rated capacity would be different regarding to their load harmonic contents. On the other hand, it is comprehended from the achieved results that the aging acceleration factor (Faa) of the DTs increases owing to their load harmonic contents.
Keywords: Available capacity, distribution transformer (DT), harmonics, aging, reliability assessment.
Full-Text [PDF 879 kb]   (652 Downloads)    
Type of Study: Research Paper | Subject: Harmonics
Received: 2022/05/28 | Revised: 2024/05/13 | Accepted: 2022/12/10
Rights and permissions
Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Creative Commons License
© 2022 by the authors. Licensee IUST, Tehran, Iran. This is an open access journal distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) license.