IEEE Transactions on Dielectrics and Electrical Insulation最新文献

{"title":"Performance Evolution and Aging Mechanism of XLPE Insulation for HVdc Cables After Different Accelerated Aging","authors":"Ying Liu;Jiazhu Yu;Meng Ma","doi":"10.1109/TDEI.2024.3517568","DOIUrl":"https://doi.org/10.1109/TDEI.2024.3517568","url":null,"abstract":"In this article, the ±200-kV crosslinked polyethylene (XLPE) cable used in Zhoushan flexible dc transmission project is targeted. Three accelerated aging schemes of continuous electrical (CE) aging, intermittent electrical (IE) aging, and electrothermal (TE) combined aging are designed, and the simulation test platform is built accordingly. The lamellar samples, cut from the XLPE insulation of the spare cable, are aged for predetermined durations under different design stresses. The samples are tested for oxidation induction time (OIT), Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), thermal stimulation current (TSC), space charge, dc conductivity, and dc dielectric strength, and the variation of various performance parameters are summarized. By analyzing the correspondence between the variation trend of each parameter and the aging process, the feature parameters that can effectively characterize dc XLPE insulation performance are determined, and the aging mechanism of dc insulation is explored. The results show that both electrical stress and thermal stress are important factors causing insulation aging, and their combined effect will significantly accelerate insulation deterioration. In addition, compared with the CE stress, the rise and fall of dc voltage will also aggravate the aging to a certain extent. Therefore, after the same time of continuous electrical stress, IE stress, and TE combined stress, the aging degree of XLPE samples increases in turn.","PeriodicalId":13247,"journal":{"name":"IEEE Transactions on Dielectrics and Electrical Insulation","volume":"32 2","pages":"1074-1083"},"PeriodicalIF":2.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143783184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experiment and Simulation of Temperature Effects on Partial Discharge and Electrical Treeing in XLPE Insulation","authors":"Yan Li;Yu Shan;Guancheng Zhen;Lingyuan Lan;Yunpeng Liu;Xiangrui Zeng;Bowen Liu","doi":"10.1109/TDEI.2024.3518484","DOIUrl":"https://doi.org/10.1109/TDEI.2024.3518484","url":null,"abstract":"Crosslinked polyethylene (XLPE) is a crucial insulating material for cables. Partial discharge (PD) and electrical treeing are key parameters for characterizing the state of XLPE. Studies have found that the temperature affects the PD and electrical treeing of XLPE. Yet, the theoretical analysis of this phenomenon is not sufficiently elaborated in-depth. To address this, this article constructs a testing platform for XLPE PD and electrical treeing, observing the development patterns of PD and electrical treeing at <inline-formula> <tex-math>$50~^{circ }$ </tex-math></inline-formula>C, <inline-formula> <tex-math>$70~^{circ }$ </tex-math></inline-formula>C, and <inline-formula> <tex-math>$90~^{circ }$ </tex-math></inline-formula>C. Experiments indicate that rising temperatures result in lower inception voltages for PDs, more frequent discharges, faster electrical tree growth, and a reduction in branching. To explore the theoretical mechanism behind the impact of temperature, this article first calculates the conductivity of cavities under different temperature conditions on a microscale using a fluid simulation model and measures the dielectric constant of XLPE at various temperatures. Then, combining a macroscale finite element simulation model, the effect of temperature on the frequency of PD occurrences is analyzed through multiscale simulation analysis. Subsequently, considering the effects of dielectric constant, critical breakdown strength, and dielectric loss tan<inline-formula> <tex-math>$delta $ </tex-math></inline-formula> at different temperatures, the phase field model is used to depict the growth of electrical trees under various temperatures. Ultimately, the simulation results show that an increase in temperature leads to a lower discharge field strength, an increase in the number of PDs, a faster growth rate of electrical trees, and a reduction in branching, which corresponds to and explains the experimental results. Temperature dependency of dielectric constant and critical breakdown strength are the key factors for the PD and electrical tree development patterns under different temperatures separately.","PeriodicalId":13247,"journal":{"name":"IEEE Transactions on Dielectrics and Electrical Insulation","volume":"32 2","pages":"674-683"},"PeriodicalIF":2.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DC Arc Flash Modeling and Analysis of Photovoltaic Arrays Using Magnetohydrodynamic Framework","authors":"Mohammed M. Al-Hassan Salim;Mohammad AlMuhaini","doi":"10.1109/TDEI.2024.3518482","DOIUrl":"https://doi.org/10.1109/TDEI.2024.3518482","url":null,"abstract":"Renewable energy systems remain one of the energy industry’s fastest-expanding sectors. Considering the recent global expansion of solar photovoltaic (PV) arrays and their corresponding dc installations, the risk of dc arc flashes on PV systems has raised safety concerns. It is necessary to develop realistic and precise criteria to evaluate arc flash levels in dc equipment, combining several solar PV circuits with considerable available fault currents. In contrast to the arc flash of ac systems, few research studies and industry standards have quantified the risks associated with PV systems, particularly with dc installations. This work is an attempt to contribute to standardized model development. The physical aspects of arc flash in PV systems are modeled, and then magnetohydrodynamics (MHDs) are utilized to perform the simulation. The MHD simulation was performed through ANSYS software, ANSYS Fluent, for fluid mechanic equations in conjunction with ANSYS Maxwell for electromagnetic equations. The empirical model developed by the Electric Power Research Institute (EPRI) for incident energy calculation on PV arrays and their published test results are compared to the resultant MHD simulation results and to certain other available industry models.","PeriodicalId":13247,"journal":{"name":"IEEE Transactions on Dielectrics and Electrical Insulation","volume":"32 2","pages":"641-648"},"PeriodicalIF":2.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Practice of Sensory Cooperation for Insulation Diagnosis of Electrical Apparatus: Probabilistic Identification and Risk Assessment","authors":"Kai Wang;Ming Ren;Chongxing Zhang;Ming Dong","doi":"10.1109/TDEI.2024.3515920","DOIUrl":"https://doi.org/10.1109/TDEI.2024.3515920","url":null,"abstract":"In this study, a set of algorithms is tailored to achieve insulation defect probability identification and risk assessment based on multiphysical detections of partial discharges (PDs). Initially, three types of PD detection units are integrated into the flange to achieve a relatively uniform detection distance. Also, the synchronous PD detection platform is constructed based on intelligent sensor units, achieving extraction of sequential PD impulse information. Then, the multiphysics energy release power (ERP) is extrapolated based on the amplitude of the measurement signal amplitude. Also, three ERP values are normalized to analyze the proportional relationship of energy releases at different stages of discharge, which is further mapped in a ternary power pattern. In addition, we develop a probability recognition model based on the ternary error-correcting output coding (ECOC) united with a support vector machine (SVM). Meanwhile, by introducing discharge data of the same type with different defect scales, it can be verified that the proposed model possesses significant robustness. Besides, Gaussian process regression (GPR) is applied to fit the relationship between the ternary power pattern and apparent discharge energy (ADE). Also, the risk index and risk level are defined based on the temporal information of ADE during the entire discharge process, which is incorporated with the pulse repetition rate to achieve the visualization of discharge risk assessment.","PeriodicalId":13247,"journal":{"name":"IEEE Transactions on Dielectrics and Electrical Insulation","volume":"32 1","pages":"55-62"},"PeriodicalIF":2.9,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143106315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Hygrothermal Conditions on Corona Aging of Silicone Rubber","authors":"Maoqiang Bi;Rui Qiu;Shuting Duan;Runkun Deng;Chen Xi;Tianyan Jiang","doi":"10.1109/TDEI.2024.3515916","DOIUrl":"https://doi.org/10.1109/TDEI.2024.3515916","url":null,"abstract":"In this research, high-temperature vulcanized silicone rubber is used as a sample to conduct a hygrothermal corona aging test. The physicochemical and electrical performance of the silicone rubber are tested under different hygrothermal conditions. The results show that the surface structure of the material is increasingly destroyed and even pulverized as humidity or temperature rises. Compared with the original samples, the static contact angle of the aged samples decreases significantly, and the static contact angle of the aged samples that exhibit pulverization expands compared with those unpulverized samples due to the large amount of small-molecule siloxanes contained in the pulverized layer. The main chain and side chain of the aged silicone rubber are damaged to varying degrees. The absorption peaks of Si–O–Si and Si–CH3 bonds in the aged samples that exhibit pulverization are higher than those of the samples that do not exhibit pulverization since the siloxane also contains Si–O–Si and Si–CH3 bonds. The aged material combines with a large number of polar groups, leading to an enhanced polarity of the silicone rubber molecules and more dielectric loss of the material. The surface resistivity and volume resistivity of the aged samples are 6.5% and 70.3% of those of the original samples at 80 °C and 95%, respectively, showing that corona discharge mainly damages the surface, rather than the interior of the material.","PeriodicalId":13247,"journal":{"name":"IEEE Transactions on Dielectrics and Electrical Insulation","volume":"32 2","pages":"992-1000"},"PeriodicalIF":2.9,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Condition Diagnosis of Composite Insulator Based on Knowledge Graph","authors":"Hua Jin;Yufang Zhang;Yuxuan Jia;Zhikang Yuan;Youping Tu","doi":"10.1109/TDEI.2024.3510219","DOIUrl":"https://doi.org/10.1109/TDEI.2024.3510219","url":null,"abstract":"Composite insulators have been widely used in power transmission system for the lightweight, high strength, and great hydrophobicity. However, the aging of the polymers in composite insulators is a key issue affecting the reliable operation, posing challenges for the condition diagnosis of composite insulators. Knowledge graph is an emerging technique for structuring existing experience and knowledge, which shows promising prospects on maintenance efficiency enhancement for composite insulators. This article introduces the condition diagnosis approach for composite insulators based on knowledge graph. First, the annotated corpus of composite insulator was constructed based on the technical reports, handbooks, open published articles, and standards. This work defined nine types of entities and nine types of relations. Then, the a lite bidirectional encoder representations from transformer (ALBERT)–bidirectional long short-term memory (BiLSTM)–conditional random field (CRF) model and the ALBERT-bidirectional gated recurrent unit (BiGRU)–attention model are employed to realize the entities and relations recognition and the <inline-formula> <tex-math>${F}1$ </tex-math></inline-formula> scores of which reach 92.49% and 92.36%, respectively, exhibiting better performance than any other models. At last, the first knowledge graph on composite insulator was constructed. There are 820 entity-relation–entity triplets, covering the basic information, environmental conditions, test methods, fault mechanisms, and so on. This work will provide an artificial intelligence tool for condition diagnosis of composite insulators.","PeriodicalId":13247,"journal":{"name":"IEEE Transactions on Dielectrics and Electrical Insulation","volume":"32 1","pages":"28-35"},"PeriodicalIF":2.9,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143106312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal Aging Comparison of Alternative Liquids for Oil-Paper High-Voltage Insulation in Current Transformers","authors":"Anthony Jeanneton;Christophe Perrier;Abderrahmane Beroual","doi":"10.1109/TDEI.2024.3508612","DOIUrl":"https://doi.org/10.1109/TDEI.2024.3508612","url":null,"abstract":"This article is aimed at the comparison of the long-term behavior of insulation systems using mineral oils to that with alternative liquids, biodegradable hydrocarbons, and ester oils, under thermal stress. The different types of oil are aged in the presence of enameled copper and Kraft paper under sealed conditions. Oil degradation is monitored by relevant aging markers, such as water content, breakdown voltage, dielectric dissipation factor (DDF), and acidity. Paper degradation is monitored through the tensile strength. The end-of-life criterion is based on paper mechanical properties. The experimental results confirm that the sealed conditions prevent oil from aging (no oxidation nor hydrolysis) and that the use of biodegradable hydrocarbon oils could be similar to that of mineral oil and that the use of esters could improve the aging behavior of paper.","PeriodicalId":13247,"journal":{"name":"IEEE Transactions on Dielectrics and Electrical Insulation","volume":"32 2","pages":"1123-1128"},"PeriodicalIF":2.9,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143783185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Partial Discharge Aging of Epoxy Insulation at Different High-Frequency Pulse Parameters and Environmental Stresses","authors":"Xingyu Shang;Lei Pang;Qinhao Bu;Qiaogen Zhang","doi":"10.1109/TDEI.2024.3502581","DOIUrl":"https://doi.org/10.1109/TDEI.2024.3502581","url":null,"abstract":"The voltage stress on high-frequency transformers (HFTs) features higher levels of repetition frequency, operating voltage, voltage dV/dt, and grid voltage superposition, which challenges the epoxy insulation of HFTs exposed to partial discharges (PDs). Wide ranges of voltage parameters (frequency, voltage, rising edge, and dc bias) and environmental stresses (temperature, humidity, gas, and pressure) are applied to the sphere-gap-insulation-plate structure for PD aging analysis. New patterns are found in this study. For example, the shape of the rising edge affects the lifetime, and the influences of humidity and dc bias are nonmonotonic. Surface charge decay and voltage dV/dt have key effects on the discharge pattern. Early failures with pulse frequencies of 50 and 100 kHz are attributed to the interaction of humidity and electric field. The erosion rate is lower at oxygen-free ambient, while higher with CO2 gas. PD parameters (PD number, PD amplitude, PD delay, PD ignition voltage, and PD frequency) and phase-resolved PD (PRPD) patterns are measured with the ultrahigh-frequency (UHF) method and discussed for all aging conditions. Cumulative PD amplitude and cumulative PD energy have a good correlation to experimental lifetime values. However, due to the transition of the PD regime, the fit model has less explainability on the influence of voltage, humidity, gas, and pressure on the lifetime, which is rarely revealed before.","PeriodicalId":13247,"journal":{"name":"IEEE Transactions on Dielectrics and Electrical Insulation","volume":"32 1","pages":"45-54"},"PeriodicalIF":2.9,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143106314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Crosslinking Agent Content on Dielectric Properties of PP Films Modified by EB Irradiation for HVDC Capacitor","authors":"Meng Xiao;Yuyan Chen;Haoliang Liu;Boxue Du","doi":"10.1109/TDEI.2024.3502000","DOIUrl":"https://doi.org/10.1109/TDEI.2024.3502000","url":null,"abstract":"The decline in breakdown strength and the rise in dielectric loss of polypropylene (PP) film at high temperatures are the key factors restricting the application of metalized film capacitors (MFCs). This article proposed a modification method using electron-beam (EB) irradiation to improve the high-temperature insulation performance of PP film for capacitors. The influence of crosslinking agent contents on the dielectric properties of irradiated crosslinked PP is investigated. The results show that the conductivity of EB-irradiated films doped with 0–2 wt% pentaerythritol triacrylate (PETA) is reduced by 26.9%–60.8% and the breakdown strength is enhanced by 2.8%–21.2% at <inline-formula> <tex-math>$125~^{circ }$ </tex-math></inline-formula>C, resulting in better dielectric properties compared to pure PP films. The formation of a 3-D network structure by crosslinking can inhibit the thermal motion of molecular chains and improve their thermal stability, consequently limiting the transport behavior of carriers. Irradiation crosslinking modification can improve the high-temperature dielectric properties of PP films. This research provides a valuable reference for the crosslinking modification of PP films serving in MFCs.","PeriodicalId":13247,"journal":{"name":"IEEE Transactions on Dielectrics and Electrical Insulation","volume":"32 2","pages":"734-741"},"PeriodicalIF":2.9,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accelerated Laboratory Aging of Synthetic Ester Dielectric Liquid","authors":"Veronika Haramija;Dijana Vrsaljko;Vedran Ðurina;Domagoj Vrsaljko","doi":"10.1109/TDEI.2024.3501995","DOIUrl":"https://doi.org/10.1109/TDEI.2024.3501995","url":null,"abstract":"Synthetic esters are liquids used in the lubricant industry, but also in the electrical industry for insulation and heat transfer. In this work, the synthetic ester is exposed to high temperatures to initiate and propagate the degradation reactions, study the degradation process, and investigate the effect of paper and water on thermal degradation. After 672 h of thermal exposure, there is no sludge, but the color of the samples is significantly changed. Fourier transform infrared spectroscopy (FTIR) is used to assess the occurrence of degradation products, the neutralization value is used to determine the total acidity, and the relative permittivity is used to correlate the influence of degradation products on the dielectric properties of the synthetic ester. Nuclear magnetic resonance (NMR) and color analysis are used to investigate the appearance and composition of the degradation products of seven selected samples. The NMR study shows that the change observed in the FTIR spectra, the neutralization value, and the relative permittivity as a function of aging conditions correspond very well with the size and shape of the 1 H NMR peak of 3.51 ppm, confirming that the formation of alcohols, ethers, and cross-links is responsible for the aging of the ester. It is found that the color change is misleading when it comes to the degradation of the synthetic ester dielectric liquid.","PeriodicalId":13247,"journal":{"name":"IEEE Transactions on Dielectrics and Electrical Insulation","volume":"32 1","pages":"367-374"},"PeriodicalIF":2.9,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143106308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}