Electric Power Systems Research最新文献_第10页

Hybrid transformer overload protection scheme integrating real-time thermal imaging and numerical relay coordination 结合实时热成像和数值继电器协调的混合式变压器过载保护方案

IF 4.2 3区工程技术

Electric Power Systems Research Pub Date : 2025-09-12 DOI: 10.1016/j.epsr.2025.112188

S. Tamilselvi , S. Ragul , V. Rajini , K.N Dinesh Babu

{"title":"Hybrid transformer overload protection scheme integrating real-time thermal imaging and numerical relay coordination","authors":"S. Tamilselvi , S. Ragul , V. Rajini , K.N Dinesh Babu","doi":"10.1016/j.epsr.2025.112188","DOIUrl":"10.1016/j.epsr.2025.112188","url":null,"abstract":"<div><div>Transformer thermal overload is a major threat to power system reliability, leading to insulation degradation, reduced service life, and unplanned outages. Conventional overload protection using numerical relays, such as the GE Multilin D60, relies primarily on current-based IEC 255–8 thermal models, which cannot directly monitor real-time temperature conditions and may delay fault detection. This study proposes a hybrid protection scheme in which real-time thermal imaging is used as the primary decision criterion, while the D60 numerical relay functions as a back-up overcurrent protection device. Surface temperature is measured using a FLIR E63900 infrared camera, and a Python-based image processing module with OpenCV and Tesseract OCR extracts temperature values from thermal images. These are processed through a heat transfer model to estimate internal core temperature. A Hybrid Protection Decision Controller (HPDC) receives both thermal and current data via Modbus TCP and issues a trip signal if either the thermal threshold is exceeded or the back-up relay detects overcurrent. Local alarms are triggered immediately upon thermal violations, and all events are logged to SCADA/EnerVista for diagnostics. Experimental validation on a 3 kVA single-phase transformer under varying load conditions demonstrated faster detection of overload conditions compared to relay-only protection, enabling proactive isolation and reducing the risk of insulation failure. The proposed scheme entails higher implementation costs than conventional relay-only solutions owing to the inclusion of thermal imaging hardware and advanced data processing systems; however, it remains a justified investment for critical transformers where the potential consequences of failure significantly outweigh the additional expenditure.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"251 ","pages":"Article 112188"},"PeriodicalIF":4.2,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145050214","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}

引用次数: 0

A dual-switch gain-enhanced step-up/step-down converter for fuel cell powertrain 用于燃料电池动力系统的双开关增益增强升压/降压转换器

IF 4.2 3区工程技术

Electric Power Systems Research Pub Date : 2025-09-12 DOI: 10.1016/j.epsr.2025.112240

Kai Zhou, Yuhan Jiang, Shuchun Gao

{"title":"A dual-switch gain-enhanced step-up/step-down converter for fuel cell powertrain","authors":"Kai Zhou, Yuhan Jiang, Shuchun Gao","doi":"10.1016/j.epsr.2025.112240","DOIUrl":"10.1016/j.epsr.2025.112240","url":null,"abstract":"<div><div>To address the critical demand for matching the fuel cell stack output voltage with the vehicle DC-bus voltage in fuel cell vehicles (FCVs), this paper proposes a novel dual-switch gain-enhanced step-up/step-down converter (SUDC). The SUDC integrates a three-inductor structure with synchronized dual switches, and the synergy of its two inductors supports an ultra-wide input voltage range and realizes high voltage gain even under low duty cycle conditions. Meanwhile, the synchronous on/off control of the two switches not only simplifies the design of the control system but also minimizes input and output ripple. Additionally, the converter adopts a common-ground structure and provides positive output voltage that further optimizes its compatibility with the power systems of FCVs. This paper deeply analyzes the converter’s operating mechanism in continuous current mode (CCM), quantifies the voltage stress on switching and nonlinear components, and calculates the optimal inductance and capacitance parameters. The proposed converter effectively reduces system losses and improves conversion efficiency. A 300 W prototype was fabricated for validation. Experimental results show that the output voltage remains stable during input voltage fluctuations and load switching, and a maximum efficiency of 96.93 % is achieved under full-load conditions, verifying the correctness of the theoretical analysis and parameter design.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"251 ","pages":"Article 112240"},"PeriodicalIF":4.2,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145050216","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}

引用次数: 0

Adaptive current differential protection of line for active distribution networks considering PV output 考虑光伏出力的有功配电网线路自适应电流差动保护

IF 4.2 3区工程技术

Electric Power Systems Research Pub Date : 2025-09-12 DOI: 10.1016/j.epsr.2025.112236

Chuhong Wu, Longhua Mu, Chongkai Fang

{"title":"Adaptive current differential protection of line for active distribution networks considering PV output","authors":"Chuhong Wu, Longhua Mu, Chongkai Fang","doi":"10.1016/j.epsr.2025.112236","DOIUrl":"10.1016/j.epsr.2025.112236","url":null,"abstract":"<div><div>The mass integration of distributed photovoltaic (PV) generation has altered the fault characteristics of active distribution networks, rendering the traditional overcurrent protection schemes inadequate in meeting reliability and sensitivity. Communication-based current differential protection exhibits excellent selectivity and rapid response, making it promising for active distribution network protection. However, due to the stochastic and fluctuating nature of PV output, the measured differential current and restraining current will fluctuate accordingly, degrading the conventional current differential protection’s performance. This paper proposes an adaptive current differential protection scheme that accounts for PV output. First, the amplitude and phase characteristics of PV output current under different output levels are qualitatively analyzed, considering the low-voltage ride-through (LVRT) requirements. Subsequently, the impact of PV output levels and fault resistance on current differential protection are investigated. An adaptive current differential protection scheme is proposed, which dynamically adjusts the operating threshold according to PV output and fault resistance. A simulation model of the active distribution network is built in Matlab/Simulink to validate the proposed scheme. Simulation results prove that the proposed protection scheme can adapt to PV output levels variations and maintain robustness against high-impedance faults and T-connected loads or T-connected PV.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"251 ","pages":"Article 112236"},"PeriodicalIF":4.2,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145050212","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}

引用次数: 0

An optimal procedure for protection coordination of directional overcurrent relay: A novel methodology 定向过流继电器保护协调的优化程序：一种新方法

IF 4.2 3区工程技术

Electric Power Systems Research Pub Date : 2025-09-12 DOI: 10.1016/j.epsr.2025.112235

Hossein Karimkhan-Zand , Kazem Mazlumi , Hamed Hashemi-Dezaki , Hesam Addin Yousefian

{"title":"An optimal procedure for protection coordination of directional overcurrent relay: A novel methodology","authors":"Hossein Karimkhan-Zand , Kazem Mazlumi , Hamed Hashemi-Dezaki , Hesam Addin Yousefian","doi":"10.1016/j.epsr.2025.112235","DOIUrl":"10.1016/j.epsr.2025.112235","url":null,"abstract":"<div><div>This paper presents an innovative approach for protection coordination of directional over-current relays (DOCRs) in real distribution micro-grid via clustering and multi-objective optimization algorithm. A new clustering algorithm based on the network variation and two novel objective functions focused on main parameters of the power grids are employed to implement this study on the DOCRs. Moreover, this paper provides a new hybrid algorithm that integrates the goal attainment algorithm into the non-dominated sorting genetic algorithm III with the assistance of linear programming (LP). It is significant to highlight that there is no evidence of study on the protection coordination problem of DOCR (PCPD) with these novel objective functions, innovative clustering technique, and unique hybrid algorithm. It is crucial to point out that the PCPD has been effectively handled for two case studies, the NOAVARAN feeder and the IEEE 14 bus system, without any miss-coordination. Furthermore, the employment of the proposed hybrid algorithm achieves a substantial reduction of approximately 50–60 % in the operation time of all relays for this case study when compared to the other recommended mixed algorithms without utilizing linear programming.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"251 ","pages":"Article 112235"},"PeriodicalIF":4.2,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145050213","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}

引用次数: 0

Verification of low-frequency signal injection method for earth-fault detection 低频信号注入法在接地故障检测中的验证

IF 4.2 3区工程技术

Electric Power Systems Research Pub Date : 2025-09-11 DOI: 10.1016/j.epsr.2025.112210

Nina Stipetic , Bozidar Filipovic-Grcic , Igor Ziger , Silvio Jancin , Bruno Jurisic , Dalibor Filipovic-Grcic , Alain Xémard

引用次数: 0

A two-stage resilience enhancement method for distribution networks considering demand response 考虑需求响应的配电网两阶段弹性增强方法

IF 4.2 3区工程技术

Electric Power Systems Research Pub Date : 2025-09-11 DOI: 10.1016/j.epsr.2025.112237

Xi Chen , Jiancun Liu , Junzhi Ren , Pengfei Li , Shuonan Hou , Xuesong Zhou

引用次数: 0

Electromagnetic transients and failed upward leaders observed during lightning activity in an onshore wind farm 在陆上风电场闪电活动中观察到的电磁瞬变和失败的向上先导

IF 4.2 3区工程技术

Electric Power Systems Research Pub Date : 2025-09-11 DOI: 10.1016/j.epsr.2025.112216

Franjo Vukovic, Bozidar-Filipovic Grcic, Nina Stipetic, Bojan Franc

{"title":"Electromagnetic transients and failed upward leaders observed during lightning activity in an onshore wind farm","authors":"Franjo Vukovic, Bozidar-Filipovic Grcic, Nina Stipetic, Bojan Franc","doi":"10.1016/j.epsr.2025.112216","DOIUrl":"10.1016/j.epsr.2025.112216","url":null,"abstract":"<div><div>At a wind farm in Croatia, lightning activity is monitored across the entire site using a lightning location system, and on a single wind turbine equipped with a Rogowski-coil-based current measurement system and a high-speed camera, all independently GPS-synchronized. In addition to recording lightning flash currents on the monitored turbine, the system is frequently triggered by electromagnetic disturbances caused by nearby lightning flashes. These include direct flashes to two neighboring turbines that share the same cable connection to the substation and have interconnected grounding systems with buried bare conductor, as well as cloud-to-ground flashes to soil near cable routes, where the resulting electromagnetic fields couple onto the cables, causing surges to propagate to the monitored turbine. The camera occasionally captures failed upward connecting leaders from the monitored turbine during these lightning events. This paper presents three cases of flashes to two neighboring wind turbines and two cases of cloud-to-ground flashes to nearby soil, all of which induced electromagnetic transients that propagated to the monitored turbine. Failed upward connecting leaders were observed in some of these cases. This paper provides observational analysis, providing Rogowski measurements of electromagnetic disturbances and failed leader currents, complemented by high-speed camera and lightning location system data.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"251 ","pages":"Article 112216"},"PeriodicalIF":4.2,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145050210","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}

引用次数: 0

Spatio-temporal Graph Neural Network with Fourier features for multi-site photovoltaic power forecasting 基于傅立叶特征的时空图神经网络多站点光伏发电功率预测

IF 4.2 3区工程技术

Electric Power Systems Research Pub Date : 2025-09-11 DOI: 10.1016/j.epsr.2025.112171

Yun Su, Mengyuan Zhang, Liang Cao, Yu Chen, YingJie Tian

{"title":"Spatio-temporal Graph Neural Network with Fourier features for multi-site photovoltaic power forecasting","authors":"Yun Su, Mengyuan Zhang, Liang Cao, Yu Chen, YingJie Tian","doi":"10.1016/j.epsr.2025.112171","DOIUrl":"10.1016/j.epsr.2025.112171","url":null,"abstract":"<div><div>Multi-site photovoltaic (PV) power forecasting is crucial for modern power systems, enhancing grid stability and maximizing renewable energy utilization. However, accurate forecasting is challenging due to strong spatiotemporal dependencies, data heterogeneity, and the need for periodic pattern modeling. To address these challenges, we propose a novel forecasting framework integrating Graph Neural Networks (GNN) with Fourier-based feature extraction. First, we construct a hyper-variable graph to jointly model the spatiotemporal dependencies of multi-site PV generation and numerical weather prediction (NWP) data within a unified framework. This structure effectively captures intricate correlations across time and space. Second, we incorporate a Fourier transform module to project time-series data into the frequency domain, facilitating the extraction of key periodic features. A low-rank approximation is employed to compress representations, mitigate redundancy, and reduce computational complexity while preserving dominant periodic components and suppressing high-frequency noise. Extensive experiments on two real-world PV datasets demonstrate the effectiveness of our approach. The proposed model achieves 1-step RMSE values of 0.0267 and 0.0228, respectively, outperforming strong baselines such as LSTNet, Autoformer, and MTGNN by up to 35.3%. These results confirm the model’s superior forecasting accuracy, generalization ability, and scalability for practical deployment in modern power systems.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"251 ","pages":"Article 112171"},"PeriodicalIF":4.2,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145050208","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}

引用次数: 0

PMU measurements enabled real-time adaptive load modeling framework PMU测量支持实时自适应负载建模框架

IF 4.2 3区工程技术

Electric Power Systems Research Pub Date : 2025-09-10 DOI: 10.1016/j.epsr.2025.112182

Manish Pandit, Ranjana Sodhi

{"title":"PMU measurements enabled real-time adaptive load modeling framework","authors":"Manish Pandit, Ranjana Sodhi","doi":"10.1016/j.epsr.2025.112182","DOIUrl":"10.1016/j.epsr.2025.112182","url":null,"abstract":"<div><div>Accurate load modeling plays a critical role in analyzing dynamic voltage stability events, such as Fault-Induced Dynamic Voltage Recovery (FIDVR), which may escalate into system-wide instability. Two important considerations in this context are the structure of the load model and the method used for parameter estimation. While significant progress has been made in developing advanced load models that account for renewable integration, demand response, etc., parameter estimation techniques remain comparatively underexplored. To address this gap, a Statistical Similarity Index (SSI)-based adaptive windowing scheme is introduced to identify faulty measurement intervals and, in turn, guide the selection of an appropriate load model structure. Specifically, a composite load model is employed during transient conditions, whereas a simpler ZIP model is used under steady-state conditions. Parameter estimation is carried out using Adam’s Stochastic Gradient Descent (ASGD) to obtain initial values, which are subsequently refined through Sequential Quadratic Programming (SQP). Simulation studies on a two-bus test system and the IEEE 39-bus network demonstrate the superior performance of the proposed method compared to conventional nonlinear algorithms, such as the Levenberg–Marquardt algorithm. Furthermore, real-time validation on RTDS and dSPACE1104 platforms confirms its suitability for practical applications.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"251 ","pages":"Article 112182"},"PeriodicalIF":4.2,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145027824","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}

引用次数: 0

An improved control method for limiting current in VSC-HVDC system under unbalanced conditions 一种改进的不平衡状态下vdc - hvdc限流控制方法

IF 4.2 3区工程技术

Electric Power Systems Research Pub Date : 2025-09-10 DOI: 10.1016/j.epsr.2025.112184

Mahmudreza Changizian , Pegah Hamedani , Amirreza Mizani

{"title":"An improved control method for limiting current in VSC-HVDC system under unbalanced conditions","authors":"Mahmudreza Changizian , Pegah Hamedani , Amirreza Mizani","doi":"10.1016/j.epsr.2025.112184","DOIUrl":"10.1016/j.epsr.2025.112184","url":null,"abstract":"<div><div>An increase in the current of the converter's switching valves beyond their rated value and fluctuations in the DC-link voltage during unbalanced fault conditions are among the most significant challenges in voltage source converter-based high voltage direct current (VSC-HVDC) systems. These issues can significantly reduce the reliability of the system. Existing methods to address these problems tend to increase the complexity of the control system and involve high computational demands. Additionally, their performance may not be suitable for all common transformer configurations in VSC-HVDC systems. In unbalanced fault scenarios, this work proposes a straightforward way to manage the current and minimize DC-link voltage variations. The suggested approach successfully regulates the current across all typical transformer winding connections to the appropriate value. The studied system is simulated under double line-to-ground and single line-to-ground fault conditions in PSCAD/EMTDC. The results confirm the effectiveness of the proposed control method across all common transformer configurations in both two-terminal and multi-terminal VSC-HVDC systems.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"251 ","pages":"Article 112184"},"PeriodicalIF":4.2,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145027830","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}

引用次数: 0