Article
Engineering, Electrical & Electronic
Yuhang Pan, Song Han, Chao Zhou, Xi Guo
Summary: This paper presents the switching transient model and analysis for an electronic on-load tap-changers (EOLTC) applied to a Sen transformer (ST). The study includes steady-state voltage and current, evaluation of current and voltage transients, dimensioning of the EOLTC and voltage spike protection. Case studies with different power factors show the influence on overlap time.
INTERNATIONAL JOURNAL OF ELECTRICAL POWER & ENERGY SYSTEMS
(2021)
Review
Engineering, Electrical & Electronic
Mohd Syukri Ali, Ab Halim Abu Bakar, Azimah Omar, Amirul Syafiq Abdul Jaafar, Siti Hajar Mohamed
Summary: This review paper summarizes the discoveries made about dissolved gas analysis (DGA) conventional methods around the decade. It provides a brief introduction of DGA and reviews various fault detection methods such as the Key Gases Method, Duval Triangle Method, Duval Pentagon Method, and Ratio Methods. The paper highlights the importance of enhancing the reliability and accuracy of each DGA method in the diagnostic process to prevent further damage to transformers.
ELECTRIC POWER SYSTEMS RESEARCH
(2023)
Article
Engineering, Electrical & Electronic
Irfan Mulyawan Malik, Anurag Sharma, R. T. Naayagi
Summary: This article proposes a comprehensive three-stage fuzzy logic approach for dissolved gas analysis (DGA) of transformer oil. By utilizing current and historical data, it emulates best practices in transformer health analysis, achieving accurate fault identification with the added benefits of time and cost savings.
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION
(2023)
Article
Engineering, Electrical & Electronic
Ibrahim B. M. Taha, Sobhy S. Dessouky, Sherif S. M. Ghoneim
Summary: DGA is utilized for diagnosing transformer faults, but lacks severity determination. By using thermodynamic theory and varying decomposing materials, two scenarios are established to enhance accuracy in predicting fault types and severity classes based on 446 samples. The proposed model shows higher accuracy compared to other DGA methods for diagnosing transformer faults and predicting fault severity.
ELECTRIC POWER SYSTEMS RESEARCH
(2021)
Article
Engineering, Electrical & Electronic
Chenguang Yan, Peng Zhang, Ya Xu, Sumei Liu, Tengyu An
Summary: This paper presents a bidirectional field-circuit coupling method for modeling inter-tap faults and verifies its effectiveness. Further simulation and analysis results reveal the variation characteristics of leakage flux and short-circuit current under inter-tap faults.
IET GENERATION TRANSMISSION & DISTRIBUTION
(2022)
Article
Engineering, Electrical & Electronic
Jorge Alfredo Ardila-Rey, Matias Patricio Cerda-Luna, Carlos Beltran Munoz, Bruno Albuquerque de Castro, Suganya Govindarajan
Summary: The electricity sector heavily relies on oil-filled electricity equipment，especially power transformers. Many of these assets have surpassed their useful life or are nearing the end of it, raising concerns about their condition. The monitoring and diagnosis of failures in liquid insulation systems play a crucial role in extending the lifespan of these equipment. However, current measurement systems have limitations, leading to the development of new measurement methods that can provide a more accurate diagnosis without technical-economic restrictions. The article introduces a novel system that utilizes an electronic nose equipped with gas sensors to measure dissolved gases in liquid insulation systems. This innovative approach shows great promise for routine monitoring and diagnosis, offering an efficient and cost-effective solution.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2023)
Article
Engineering, Electrical & Electronic
Dionysios Moutevelis, Javier Roldan-Perez, Milan Prodanovic, Santiago Sanchez-Acevedo
Summary: This article analyzes the parameter stability and power transfer limits of active distribution networks with power converters and load tap changers using bifurcation theory. The results show the impact of converter parameters and limits on system stability, as well as the importance of reactive power support from converters in improving stability margins.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2022)
Article
Engineering, Electrical & Electronic
Yan Yan, Hongzhong Ma, Miaowen Wen, Shuping Dang, Honghua Xu
Summary: This paper proposes a feature selection method for identifying mechanical faults in OLTCs in smart grids with EVs. By combining multi-feature fusion with the K-nearest neighbors algorithm and the improved whale optimization algorithm, it improves accuracy and can speed up the promotion of EVs and the establishment of intelligent transportation environments.
IEEE SENSORS JOURNAL
(2021)
Article
Engineering, Mechanical
Wongon Kim, Sunuwe Kim, Jingyo Jeong, Hyunjae Kim, Hyeonchan Lee, Byeng D. Youn
Summary: This study proposes a digital twin approach for OLTCs using pre-processing of the vibration signal, data-driven dynamic model updating, and optimization-based operating condition estimation. The proposed method effectively estimates the mechanical state and faulty operating condition, overcoming the shortcomings of traditional methods. Numerical and experimental results validate the effectiveness of the proposed approach.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Xingzu Yang, Shuaibing Li, Yi Cui, Yongqiang Kang, Zongying Li, Hongwei Li, Haiying Dong
Summary: This paper analyzes the effect of sliding speed on the electrical conductivity and friction properties of an on-load tap changer's contact pair. The study found that increasing sliding speed leads to an increase in contact resistance and changes in wear mechanisms. Non-mechanical factors play a significant role in the deterioration of the contact surface.
Article
Computer Science, Information Systems
Muhammad Aslam, Inzamam Ul Haq, Muhammad Saad Rehan, Abdul Basit, Muhammad Arif, Muhammad Iftikhar Khan, Muhammad Sadiq, Muhammad Naeem Arbab
Summary: The paper presents a comparative analysis of different thermal models for predicting the hotspot temperature and top oil temperature of power transformers, as well as proposes a new thermal model for monitoring transformer operation in real-time. The model is experimentally validated and found to be in good agreement with actual field data.
Article
Engineering, Electrical & Electronic
Zhenhuan Ding, Xiaoge Huang, Zhao Liu, Ziang Zhang
Summary: This paper proposes a two-level scheduling algorithm to address voltage regulation in power distribution systems by coordinating the customer-owned BESS and utility-owned LTCs. The algorithm aims to find the optimal operation scheduling that maximizes economic payback and satisfies system operation rules. Simulation results on IEEE distribution test feeders validate the effectiveness of the proposed algorithm.
IEEE TRANSACTIONS ON POWER DELIVERY
(2022)
Article
Energy & Fuels
Bonginkosi A. A. Thango
Summary: This paper discusses the issue of fault prediction in electrical power transformers and proposes a unique classification algorithm, Binary Classification Support Vector Machine (BCSVM), which achieves better results compared to conventional methods.
Article
Computer Science, Information Systems
Christof Riedmann, Uwe Schichler, Wolfgang Hausler, Wolfgang Neuhold
Summary: Dissolved gas analysis (DGA) is commonly used for assessing and monitoring the condition of transformers. Gas losses at the phase interface can distort the interpretation basis for DGA and lead to false assessments. This study investigates the influences on gas losses and proposes a model for consideration in condition assessments. The results demonstrate the effects of geometry and temperature on gas losses, and show the potential for correcting degassing using the developed model within certain limits. Methodologies for determining the model are also discussed.
Article
Chemistry, Physical
Peipei Zhao, Mingcong Tang, Dongzhi Zhang
Summary: This paper performs simulations to investigate the sensing performance of different metal-modified PdSe2 for five dissolved gases in transformer oil. The results show that Rh-PdSe2 has the best desorption for H-2 at room temperature and can be used as a candidate material for H-2 detection. PdSe2 also shows good adsorption and desorption performance for H-2 and C2H2 at high temperatures, making it suitable for gas detection in high-temperature environments. This work provides a theoretical basis and preliminary ideas for experimenters.
APPLIED SURFACE SCIENCE
(2022)
