Article
Chemistry, Physical
Haidan Lin, Jiachang Guo, Daiyong Yang, Shouxue Li, Dan Liu, Changyan Liu, Zilong Zhang, Bolin Wang, Haifeng Zhang
Summary: The detection of dissolved gas in transformer oil is crucial for early fault diagnosis and security monitoring of power systems. Different Pd/C, Pd/C-R and Pd/NC materials were synthesized and evaluated, and it was found that nitrogen-doped Pd/NC exhibited excellent gas-sensitive performances for H-2/CO/C2H2 gases.
Review
Chemistry, Multidisciplinary
Zulbirri Faizol, Farid Zubir, Norhafezaidi Mat Saman, Mohd Hafizi Ahmad, Mohamad Kamal A. Rahim, Osman Ayop, Muzammil Jusoh, Huda A. Majid, Zubaida Yusoff
Summary: This article reviews the current methods for detecting and locating partial discharge signals in high-voltage equipment, compares their efficacy, and summarizes the future direction of research in PD detection.
APPLIED SCIENCES-BASEL
(2023)
Article
Engineering, Electrical & Electronic
Yan Zhao, Shu-Sheng Zheng, Xiao-Hu Yan, Ju Kong, Dong-Chen Liu, Ai-Xu Zhong
Summary: This article investigates the development of a PD detection sensor based on the unique propagation characteristics of PD signals within the transformer tank seam. It analyzes the influence of parameters on propagation characteristics, simulates and analyzes the frequency domain and polarization characteristics of typical defect discharge signals in the seam, and designs an ultra-wideband PD sensor. The experimental results show that the sensor can detect discharge signals more accurately compared to traditional Bow-tie antennas.
IEEE SENSORS JOURNAL
(2023)
Article
Engineering, Electrical & Electronic
Josue Rodriguez, Jose Contreras, Carlos Gaytan
Summary: This study evaluates the gas generation of a new soybean-based natural ester liquid in distribution and power transformers through lab-scale testing, and discusses predicting transformer fault types using different diagnostic methods. Results show that overheating issues in natural esters are associated with ethylene, while high energy faults and partial discharge faults are linked to acetylene and hydrogen, respectively. The Duval triangle method is confirmed as the most reliable approach for diagnosing natural ester liquids.
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION
(2021)
Article
Energy & Fuels
Jiaxin Liu, Zijian Zhao, Yuanchen Zhong, Chenchen Zhao, Guogang Zhang
Summary: This paper presents a time series forecasting model based on the SARIMA model to predict the dissolved gas concentration in power transformer oil. The SARIMA model shows the most accurate and stable performance in predicting the trend component of the gas, and considering external factors improves the accuracy of the predictions.
Article
Engineering, Multidisciplinary
T. Mariprasath, M. Ravindaran
Summary: This research conducted partial discharge tests on thermally aged liquids and solid insulating materials to analyze the withstand ability of insulating oil under applied electrical stresses. The experimental results showed that rice bran oil and sunflower oil had higher breakdown strength and fire resistance characteristics compared to mineral oil. The rate of reduction in critical properties for rice bran oil was also lower.
SADHANA-ACADEMY PROCEEDINGS IN ENGINEERING SCIENCES
(2022)
Article
Chemistry, Analytical
Yuan Tian, Hui Qiao, Tao Yao, Shuguo Gao, Lujian Dai, Jun Zhao, Ying Chen, Pengcheng Xu
Summary: A high-performance acetylene sensor was fabricated on a microhotplate chip using In2O3 as the sensing material. Pd-Ag core-shell nanoparticles were synthesized and used as catalysts to achieve high sensing response to acetylene.
Article
Chemistry, Analytical
Vijay V. Kondalkar, Jihoon Park, Keekeun Lee
Summary: This report introduces a MEMS gas sensor system for dissolved hydrogen gas analysis, providing effective monitoring of transformer operational status and maintenance of safety standards in the power grid.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Engineering, Multidisciplinary
Walid S. S. Salah, Ahmed H. H. Gad, Mahmoud A. A. Attia, Soliman M. M. Eldebeikey, Abdelhady R. R. Salama
Summary: This research presents a design for a compact double layer printed UHF antenna to detect and discriminate various types of PD activity in a power transformer. The designed antenna has a small/simple size and ultra-wide frequency passband, making it suitable for detecting different types of PD activity in power transformers.
AIN SHAMS ENGINEERING JOURNAL
(2022)
Article
Chemistry, Physical
Lin Mu, Dachang Chen, Hao Cui
Summary: This study investigates the adsorption and sensing of dissolved gases in transformer oil on a single Pd atom doped Janus HfSeTe monolayer (Pd-HfSeTe). The results show that single Pd atom has stronger adsorption capability on the HfSeTe surface compared to bulk Pd. The doping of Pd enhances the adsorption strength of CO, C2H2, and C2H4. The electronic properties indicate that Pd-HfSeTe can detect C2H4 with higher selectivity as both resistance-type and work-function type gas sensor.
SURFACES AND INTERFACES
(2022)
Article
Chemistry, Multidisciplinary
Yang Chen, Zhentao Wang, Zhao Li, Hongquan Zheng, Jingmin Dai
Summary: The paper presents the development of an online detection setup for measuring the concentration of multicomponent gases dissolved in transformer insulating oil. The setup includes an oil-gas separation system and an optical system using TDLAS to determine gas concentration. The calibration experiments show linear results for the six target gases, with the setup providing an effective basis for online detection of dissolved gas in transformer insulating oil.
APPLIED SCIENCES-BASEL
(2021)
Article
Nanoscience & Nanotechnology
Mingcong Tang, Peipei Zhao, Lin Wang, Liang Zhu, Zhaofeng Wu, Dongzhi Zhang
Summary: This paper investigates the adsorption characteristics and sensitivity processes of Ag/Pd/Pt-doped NbSe2 monolayer on various gases in oil-immersed transformers through first-principles calculations. It is found that the Ag/Pt-NbSe2 system exhibits excellent adsorption/desorption properties for H2 at both ambient and high temperatures, while the Pd-NbSe2 system only shows great desorption properties for H2 at high temperature. Micro-nanomaterials prepared by Ag/Pd/Pt-NbSe2 are expected to be used as sensors for detecting H2, while those prepared by NbSe2 and Pd/Pt-NbSe2 can be used for CH4 and CO2 sensing.
ACS APPLIED NANO MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
Lakshmi Tharamal, P. Preetha, T. K. Sindhu
Summary: This article proposes a method to classify in-service transformer oil by assessing its level of degradation through partial discharge testing. Statistical analysis and postprocessing techniques are applied, resulting in a high level of classification accuracy. This research is of great importance for ensuring the integrity and reliability of transformer equipment.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2022)
Article
Chemistry, Physical
Vladimir Poluzanski, Nenad Kartalovic, Bosko Nikolic
Summary: This research analyzes the influence of transformer oil temperature on the accuracy of the all-acoustic non-iterative method for partial discharge location, quantifying the contribution through analytical, statistical, and Monte Carlo methods. The study reveals that the contribution varies significantly with different positions of partial discharge and acoustic sensors, proposing a procedure to control the contribution in practice.
Article
Chemistry, Analytical
Yuan Wang, Guo-ming Ma, Diya Zheng, Wei-qi Qin, Jun Jiang, Hong-yang Zhou, Chao Yan
Summary: This paper presents an optical acetylene sensing method based on HC-PCF and FLRDS, utilizing focused ion beam technique to process micro-sized channels. The FLRDS system achieves a minimum detection limit of 0.71 ppm, improving detection stability and providing a new idea for online monitoring of dissolved gases in transformer oil.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Energy & Fuels
Abdelhameed Ibrahim, El-Sayed M. El-kenawy, A. E. Kabeel, Faten Khalid Karim, Marwa M. Eid, Abdelaziz A. Abdelhamid, Sayed A. Ward, Emad M. S. El-Said, M. El-Said, Doaa Sami Khafaga
Summary: This study predicts the performance of a hybrid solar desalination system using an enhanced prediction method based on a supervised machine-learning algorithm. The hybrid system consists of a humidification-dehumidification (HDH) unit and a single-stage flashing evaporation (SSF) unit. The proposed algorithm is built upon the Al-Biruni Earth Radius (BER) and Particle Swarm Optimization (PSO) algorithms. Experimental data is used to train and evaluate the BER-PSO algorithm. The results show that the proposed method has great ability to identify the nonlinear relationship between operating circumstances and process responses, and it outperforms other analyzed models in predicting outlet temperatures and pressure drop values.
Article
Construction & Building Technology
Xinyi Hu, Juha Jokisalo, Risto Kosonen, Matti Lehtonen, Teng Shao
Summary: High heating expenses in Chinese rural houses in severe cold regions are mainly caused by high heating demand, inferior envelope performance, and low-efficiency heating equipment. This study presents cost-optimal envelope renovation solutions using simulation-based multi-optimization analysis, which can reduce CO2 emissions and lifecycle cost (LCC). The results show that intermittent and continuous heating can cut CO2 emissions by 30% and 40% respectively, and the LCC with continuous heating decreased by 8% after renovation。
Article
Energy & Fuels
Siyu Zhou, Yang Han, Karar Mahmoud, Mohamed M. F. Darwish, Matti Lehtonen, Ping Yang, Amr S. Zalhaf
Summary: Achieving sustainable development relies on integrating renewable energy sources, energy storage systems, and electric vehicles. This study presents a unified planning model that includes renewable energy-based distributed generation, energy storage systems, and electric vehicle charging stations. Multiple scenarios are generated using a Latin Hypercube Sampling method to capture the uncertainty of renewable energy and load demand. Stochastic EV charging behaviors are represented by probability density functions, and the capacity loss of energy storage systems and EV batteries is calculated using a battery degradation model based on depth of discharge. The battery degradation cost is incorporated into the objective of the planning model, and a piecewise linearization approach is used to convert the problem into a mixed-integer linear programming model. Numerical results demonstrate the significant role of exploitable capacity loss in asset planning and the preservation of battery sustainability and lifetime through considering battery degradation in the optimization model.
Article
Engineering, Electrical & Electronic
Rahman Azis Prasojo, Muhammad Akmal A. Putra, Ekojono, Meyti Eka Apriyani, Anugrah Nur Rahmanto, Sherif S. M. Ghoneim, Karar Mahmoud, Matti Lehtonen, Mohamed M. F. Darwish
Summary: Power transformers are critical and expensive assets in the power system. Dissolved gas analysis (DGA) is an important test to ensure system reliability by detecting fault types through analyzing dissolved gases in transformer oil. The graphical Duval pentagon is a widely used DGA interpretation technique, but has limitations in handling large amounts of data. This study proposes a machine-learning-based fault identification model using the Random Forest algorithm with SMOTE preprocessing, achieving high accuracy and consistency in fault diagnosis.
ELECTRIC POWER SYSTEMS RESEARCH
(2023)
Article
Thermodynamics
Siyu Zhou, Yang Han, Shuheng Chen, Ping Yang, Karar Mahmoud, Mohamed M. F. Darwish, Lehtonen Matti, Amr S. Zalhaf
Summary: This paper proposes a bi-level optimization model to optimize the planning of the distribution network, considering multiple renewable energy and energy storage system functionalities to ensure economic and reliable operation. The model comprehensively considers seasonal changes and uncertainties, including renewable energy, load fluctuation, and contingency outage. The effectiveness of the proposed model is validated through numerical studies, demonstrating improved economic and reliability for the distribution network.
Editorial Material
Engineering, Electrical & Electronic
Mohamed M. F. Darwish, Mahmoud Elsisi, Mostafa M. Fouda, Diaa-Eldin A. Mansour, Matti Lehtonen
IET GENERATION TRANSMISSION & DISTRIBUTION
(2023)
Article
Engineering, Electrical & Electronic
Naveed Qammar, Ammar Arshad, Robert John Miller, Karar Mahmoud, Matti Lehtonen
Summary: This article proposes a framework to find the hosting capacity (HC) for a grid and applies it to 503 simulated LV distribution feeders in Finland to determine their HCs and the most effective network parameters in defining a specific HC. Different machine learning models were implemented on generated data, with logistic regression, KNN, and SVM achieving accuracy values of 0.89, 0.84, and 0.81, respectively. The findings show that this machine learning-based technique allows distribution network operators to find the HC without using deterministic or probabilistic approaches.
IET GENERATION TRANSMISSION & DISTRIBUTION
(2023)
Review
Engineering, Electrical & Electronic
Diaa-Eldin A. Mansour, Mohamed Numair, Amr S. Zalhaf, Rawda Ramadan, Mohamed M. F. Darwish, Qi Huang, Mohamed G. Hussien, Omar Abdel-Rahim
Summary: This paper reviews the applications of Internet of Things (IoT) and digital twin technology in electrical power systems. The paper discusses the role of IoT systems and the digital twin structure in smart grids, as well as the use of IoT and digital twin technology for energy management in various applications such as smart homes, smart buildings, smart grids, smart industries, smart transportation, and smart cities. The paper also explores the applications of IoT and digital twin technology for condition monitoring and diagnosis in electrical power systems, as well as their applications in power electronic systems. Finally, the paper discusses the challenges and opportunities of applying IoT and digital twin technology to electrical power systems and provides recommendations for future research.
IET GENERATION TRANSMISSION & DISTRIBUTION
(2023)
Article
Physics, Multidisciplinary
Gamal M. Mahmoud, Hesham Khalaf, Mohamed M. Darwish, Tarek M. Abed-Elhameed
Summary: In this paper, the generalization of combination synchronization (GCS) of chaotic dynamical models with integer, fractional and distributed-orders is studied for the first time. The definition and scheme of GCS using tracking control technique among two drive integer and fractional-order models and one response distributed-order model are presented. A theorem is established to provide the analytical formula for the control functions to achieve GCS. Numerical calculations support the analytic results and an example is given to validate the effectiveness of the control functions. Additionally, the chaos desynchronization of fractional-order and distributed-order hyperchaotic strongly coupled Lorenz models is also studied. Encryption and decryption of color image based on GCS are introduced, and information entropy, pixel correlation analysis, and histograms are used to evaluate the experimental results of color image encryption.
Article
Chemistry, Analytical
Hesham S. Karaman, Diaa-Eldin A. Mansour, Matti Lehtonen, Mohamed M. F. Darwish
Summary: Mineral oil is commonly used as an insulating liquid in power transformers, but for environmental reasons, natural ester oil has been introduced as a potential alternative. This study investigated the effects of mixing natural ester oil with aged mineral oil, and found that a mixture of 90% natural ester oil and 10% mineral oil aged for 6 days showed the best performance, with approximately 43% and 48% improvement in dielectric strength and relative permittivity, respectively, compared to fresh mineral oil.
Article
Computer Science, Information Systems
Osama E. Gouda, Adel Z. El Dein, Elsayed Tag-Eldin, Matti Lehtonen, Mohamed M. F. Darwish
Summary: One important objective of this article is to present a novel approach to study the current density and ground surface potential around the area surrounding earthed and isolated systems in the event of a line-to-earth fault. The present study is done in the case of uniform and two layers of soil. A grounded system is usually implemented with rods and/or grounding grids, and the impact of both on step and touch potentials and current density are investigated, discussed, and adapted.
Article
Computer Science, Information Systems
Nagwa F. Ibrahim, Karar Mahmoud, Matti Lehtonen, Mohamed M. F. Darwish
Summary: This paper proposes a novel variable-current-t-reference calculation method to minimize power fluctuations and current harmonics in grid-connected solar systems. The controller regulates constructive and destructive sequences in a static framework, improving dynamic performance and enabling the selection of suitable controls in the presence of network defects. The study also suggests comparing different MPPT methodologies to maximize energy output. The simulation results validate the proposed computation approach.
