Electric Power Systems Research最新文献

{"title":"A novel reinforcement learning-based multi-objective energy management system for multi-energy microgrids integrating electrical, hydrogen, and thermal elements","authors":"Ehsan Hosseini ,&nbsp;Pablo García-Triviño ,&nbsp;Pablo Horrillo-Quintero ,&nbsp;David Carrasco-Gonzalez ,&nbsp;Carlos A. García-Vázquez ,&nbsp;Raúl Sarrias-Mena ,&nbsp;Higinio Sánchez-Sainz ,&nbsp;Luis M. Fernández-Ramírez","doi":"10.1016/j.epsr.2025.111474","DOIUrl":"10.1016/j.epsr.2025.111474","url":null,"abstract":"<div><div>This paper presents a Reinforcement Learning (RL)-driven multi-objective function-based energy management system (RL-MOF-EMS) for optimizing the economic dispatch and lifespan of electrical, thermal, and hydrogen systems within a multi-energy microgrid (MEMG). By leveraging a discrete Deep Q-Network (DQN) agent, the RL-MOF-EMS dynamically balances energy distribution across multiple resources, ensuring optimal thermal and electrical power allocation. The system evaluates three distinct single-objective functions under different EMS strategies: 1) priority-based regulator (PBR), 2) proportional regulator (PR), and 3) particle swarm optimization (PSO). These objectives are then combined into a complex multi-objective optimization problem, solved using the RL-based DQN agent, which selects from 8 dynamic actions to enhance learning speed and accuracy. This RL approach not only accelerates decision-making but also ensures robust and real-time optimization, driving the efficient operation of MEMG systems. The performance is rigorously tested in Simulink under diverse weather conditions and fluctuating thermal and electrical demand profiles. The results are compared against an EMS based on a nonlinear MATLAB optimizer, demonstrating the effectiveness of the RL-MOF-EMS in coordinating power flows from energy sources and storages. The proposed RL-EMS outperforms the FM-EMS by achieving lower operational costs (0.704 €/h vs. 0.767 €/h) and heating costs (1.327 €/h vs. 1.484 €/h), while maintaining a higher hydrogen utilization rate (71.43 % vs. 63.15 %) and state of charge (60.83 % vs. 58.30 %). Additionally, RL-EMS demonstrates superior multi-objective balancing, with a lower overall MOF value and improved performance across key objectives, including operational efficiency, degradation minimization, and heating cost reduction.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"242 ","pages":"Article 111474"},"PeriodicalIF":3.3,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143132334","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":"Solving multi-area economic dispatch with disjoint operating regions using special ordered sets","authors":"Hossein Sharifzadeh","doi":"10.1016/j.epsr.2025.111454","DOIUrl":"10.1016/j.epsr.2025.111454","url":null,"abstract":"<div><div>Electricity market operators should solve multi-area economic dispatch (MAED) in shorter periods because of increasing net load variation from fluctuating renewables and demands. Optimization algorithms need to solve the MAED problem within a few minutes, ideally under five minutes, due to increasing net load variations. However, traditional algorithms are less effective in solving the non-convex MAED due to the non-convex characteristics of generating units, such as disjoint operating regions and throttling loss effects. This work proposes a fast, effective, and reliable method using special ordered sets (SOS) advantages to solve the non-convex MAED efficiently. The method proposed represents the DORs and TLEs using SOS type 1 (SOS1) and type 2 (SOS2), respectively, to develop an SOS-based MAED (SOS-MAED). Then, one can efficiently solve the SOS-MAED using optimization software equipped with SOS branching techniques. We test the proposed SOS-MAED in four case studies with convex and non-convex structures. The obtained results demonstrate the strength of the proposed SOS-MAED in terms of efficiency and solution quality compared with earlier algorithms. Moreover, the SOS-MAED seems faster than its equivalent mixed integer model.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"242 ","pages":"Article 111454"},"PeriodicalIF":3.3,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131125","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":"Optimal bidding strategy for price maker battery energy storage systems in energy and regulation reserves markets","authors":"Rafael Garcia T.,&nbsp;Maximiliano Martinez","doi":"10.1016/j.epsr.2025.111461","DOIUrl":"10.1016/j.epsr.2025.111461","url":null,"abstract":"<div><div>This study presents a novel methodology to address bi-level optimization challenges, specifically targeting Battery Energy Storage Systems (BESSs) in competitive energy and regulation reserve markets. The approach Incorporates non-convex constraints inherent in real-world market models by sequentially solving each problem level, avoiding simplifications into single-level equivalents. Heuristic optimization, specifically the Particle Swarm Optimization (PSO) algorithm, is implemented to solve the complex solution space. The methodology incorporates a degradation cost model and semi-elastic demand behavior to emulate real market conditions. A performance analysis identifies optimal PSO parameters, demonstrating the methodology’s scalability for real-size transmission networks. Extensive simulations underscore the transformative role of BESSs as price-maker assets, revealing the critical impact of non-convex constraints, quantity-price bidding, and load modeling on strategy and profitability, achieving up to a 10% increase in profit compared to models that overlook these aspects.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"242 ","pages":"Article 111461"},"PeriodicalIF":3.3,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143132333","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":"Coordination of distance and positive sequence voltage-restrained overcurrent relays for protection of distribution systems with PV plants","authors":"Priyanka Mishra ,&nbsp;Ashok Kumar Pradhan ,&nbsp;Prabodh Bajpai","doi":"10.1016/j.epsr.2025.111432","DOIUrl":"10.1016/j.epsr.2025.111432","url":null,"abstract":"<div><div>Fault ride-through capability of solar photovoltaic (PV) plants limit the applicability of only current based overcurrent relays in a distribution system. Both voltage and current based positive sequence voltage-restrained overcurrent relays (psVROCRs) provide a reliable operation to such systems. However, trip time characteristics of psVROCR leads to high decision time for faults at the far end of a long distribution line. Distance relay may be a viable option for providing faster protection to long lines. Therefore, a protection technique using a combination of three-dimensional trip characteristics of psVROCR for short lines and fixed setting distance relays for long lines is proposed to reduce relay decision time, ensuring coordination in PV-connected distribution systems. A technique to resolve the coordination problem of psVROCR with variable trip time-impedance relation and the distance relay with constant trip time-impedance relation for in-zone fault in the required time frame is also devised. Mathematical analysis validates the ability of the proposed method to provide faster protection. Performance of the proposed method is tested for fault ride-through capability of solar plants, operating at different power factor modes, close-in fault in 30-bus systems, and found to be an effective solution for coordinated protection. Comparative assessment reveals the strength of proposed method.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"242 ","pages":"Article 111432"},"PeriodicalIF":3.3,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131192","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 hybrid curriculum learning and tree search approach for network topology control","authors":"G.J. Meppelink,&nbsp;A. Rajaei,&nbsp;Jochen L. Cremer","doi":"10.1016/j.epsr.2025.111455","DOIUrl":"10.1016/j.epsr.2025.111455","url":null,"abstract":"<div><div>Transmission network topology control offers cheap flexibility to system operators for mitigating grid congestion. However, finding the optimal sequence of topology actions remains a challenge due to the large number of possible actions. Although reinforcement learning (RL) approaches have attracted interest for long-term planning in large combinatorial action spaces, they encounter challenges such as training stability, sample efficiency, and unforeseen consequences of RL actions. Addressing these challenges, this paper proposes a hybrid curriculum-trained RL and Monte Carlo tree search (MCTS) approach to determine sequential topological actions for mitigating grid congestion. The curriculum-based approach stabilizes training by first pre-training a policy network through supervised imitation learning, followed by RL training. The policy network guides the MCTS to simulate promising future trajectories, mitigating unforeseen consequences and identifying long-term strategies to improve grid security. Moreover, the MCTS-verified actions are used for RL training, enhancing sample efficiency and training time. A distance factor is added to the MCTS, which improves convergence by prioritizing actions closer to congestion. Numerical results on the IEEE 118-bus system show that the proposed hybrid approach improves the timesteps survived by 30% compared to a standard RL approach, and by 5% compared to a brute-force baseline. Additionally, the inclusion of the distance factor increases the timesteps survived by 15%. These results highlight the potential of the proposed method for real-world applications of using sequential topological actions to effectively relieve grid congestion.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"242 ","pages":"Article 111455"},"PeriodicalIF":3.3,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced detection of power transformer winding faults through 3D FRA signatures and image processing techniques","authors":"Xiaozhen Zhao ,&nbsp;Ge Wu ,&nbsp;Dingqian Yang ,&nbsp;Guanghu Xu ,&nbsp;Yunqi Xing ,&nbsp;Chenguo Yao ,&nbsp;Ahmed Abu-Siada","doi":"10.1016/j.epsr.2025.111433","DOIUrl":"10.1016/j.epsr.2025.111433","url":null,"abstract":"<div><div>Power transformers may experience various winding deformations because of short circuit faults and other external factors. Frequency response analysis (FRA) technique has been the most popular method for detecting such winding deformations. However, current practices primarily focus on the magnitude response, often neglecting the phase response, which holds vital information. Furthermore, the identification and quantification of internal transformer faults largely depend on hands-on experience, leading to inconsistent interpretations of similar FRA signatures. Currently, there is no universally accepted standard for FRA interpretation. In this regard, digital image processing (DIP) technique is employed on a new three-dimensional (3D) FRA signature. The proposed new 3D signature integrates the frequency, magnitude, and phase angle of the conventional FRA signature into one 3D plot that is manipulated using DIP code to extract unique texture analysis features. These features are used to classify various faults through clustering them in a ternary diagram. The proposed technique is validated through extensive experimental analysis on a custom-made three-phase transformer. Results attest the robustness of the proposed technique.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"242 ","pages":"Article 111433"},"PeriodicalIF":3.3,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143132259","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":"Design and analysis of a peak current-limiting device using an oscillating zero-crossing circuit","authors":"Yingang Yu ,&nbsp;Tianhong Pan ,&nbsp;Jun Rui ,&nbsp;Shan Chen ,&nbsp;Yuan Fan","doi":"10.1016/j.epsr.2025.111465","DOIUrl":"10.1016/j.epsr.2025.111465","url":null,"abstract":"<div><div>Excessive short-circuit currents present a significant threat to the operational stability of equipment in the industrial and mining enterprises distribution networks. To address this challenge, a novel short-circuit current-limiting strategy is proposed in this work, which combines an LC high-frequency oscillation circuit with a power frequency current circuit in parallel. The configuration forces the short-circuit current to reach the zero-crossing point, promoting electrical disconnection in a vacuum environment. The presented strategy integrates an ultrafast vacuum circuit breaker with a mechanical breaker, which is connected in parallel with an LC oscillation circuit designed to enforce zero-crossing interruption of the main circuit. Additionally, a current-limiting reactor is utilized to effectively suppress the short-circuit current. Furthermore, the working mechanism of current-limiting device, the design of its key parameters, and the potential applications in actual distribution networks are also analyzed. Both simulation and experimental results confirm that the designed device effectively reduces the peak short-circuit currents to below 70 %, significantly mitigating their impact on distribution network equipment and greatly enhancing the operational stability of system.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"242 ","pages":"Article 111465"},"PeriodicalIF":3.3,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143132258","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":"Feasible region analysis of PV hosting capacity in active distribution networks via a two-stage optimization approach","authors":"Jian Wang ,&nbsp;Xin Xing ,&nbsp;Zhixin Fu ,&nbsp;Chen Hai ,&nbsp;Haoming Liu ,&nbsp;Qianggang Wang","doi":"10.1016/j.epsr.2025.111446","DOIUrl":"10.1016/j.epsr.2025.111446","url":null,"abstract":"<div><div>The increasing integration of distributed photovoltaic (PV) capacity gradually causes the problem of overvoltage and overload in distribution networks. To analyze the coupling of PV capacity at different buses, this study proposes a feasible region method to characterize the distributed PV hosting capacity in an active distribution network (ADN). First, the characteristics and main influencing factors of the feasible region of distributed PV capacity are analyzed. Second, an optimal power flow model for ADN is established through the linearization relaxation method. Third, a two-stage optimization model is built to characterize the feasible region of distributed PV capacity. The first-stage model determines the on-load tap changer action state at the vertex of the feasible region. The second-stage model characterizes the whole feasible region via multiparametric programming. Last, the effectiveness of the model is verified by simulating the modified PG&amp;E69 system, and the improvement effects of different adjustable resources on PV hosting capacity are compared.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"242 ","pages":"Article 111446"},"PeriodicalIF":3.3,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131120","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":"Maximizing hosting capacity of renewable energy sources in unbalanced distribution networks using multi-objective optimization approach","authors":"Abdallah Nazih,&nbsp;Adel A.Abou El-Ela,&nbsp;Eman S. Ali","doi":"10.1016/j.epsr.2025.111458","DOIUrl":"10.1016/j.epsr.2025.111458","url":null,"abstract":"<div><div>In this paper, an effective optimization method is proposed based on whale optimization algorithm (WOA) to maximize renewable energy sources hosting capacity (HC) under uncertain conditions in unbalanced distribution networks. Therefore, multi-objective optimization problem is formulated to maximize distributed generators (DGs) HC besides maximizing losses and voltage unbalance reduction percentages. Matrix-based backward/forward sweep method is utilized for implementing the power flow computations in unbalanced networks. Photovoltaic (PV) and wind turbines (WT) DGs are optimally allocated by determining DGs sizes, locations, power factors and connection phases. Uncertainty of PV, WT and load demands are considered. Reduction criterion is employed to reduce numerous numbers of uncertain scenarios. The proposed WOA is evaluated with IEEE 13-node and 123-node unbalanced test feeders at different cases studied to validate its effectiveness. In IEEE 13-node system, HC reaches 3.421 MW with reduction in losses and voltage unbalance by 64.75 % and 15.03 %, respectively. In IEEE 123-node system, HC reaches 2.541 MW with reduction in losses and voltage unbalance by 61.64 % and 3.68 %, respectively. Moreover, Wilcoxon statistical tests are performed, and a comparative study is demonstrated with well-known metaheuristic algorithm to verify the proposed WOA performance. Attained results emphasize the efficacy and appliance of proposed WOA.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"242 ","pages":"Article 111458"},"PeriodicalIF":3.3,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131121","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":"Review of insulation monitoring and fault locating devices for ungrounded low voltage network: Commercial products, patents, research and innovation","authors":"Azharudin Mukhtaruddin ,&nbsp;Muhammad Mokhzaini Azizan ,&nbsp;Mohd Faris Ariffin","doi":"10.1016/j.epsr.2025.111464","DOIUrl":"10.1016/j.epsr.2025.111464","url":null,"abstract":"<div><div>Ungrounded or isolated-earth (IT) systems for electrical supply networks offer guaranteed continuity under fault conditions but require the installation of permanent insulation monitoring devices (IMDs). These devices are critical for monitoring and alerting when faults occur, as unaddressed faults can lead to dangerous network conditions. This comprehensive review examines the current state and future directions of IMD and fault-locating device (IMD-FLD) technologies. The paper analyses three primary aspects; evaluates three common insulation monitoring technologies applied in products from several leading manufacturers, with a particular focus on fault location capabilities; a discussion granted patents provides insight into the technological evolution and current innovations in IMD and IMD-FLD systems; and finally, we review selected current research that shows potential for advancing IMD and IMD-FLD technology. By synthesising insights from commercial products, patents, and academic research, this paper identifies key trends and technological gaps in IMD and FLD development. Our analysis reveals significant opportunities to enhance the functionality and effectiveness of these devices, particularly in fault location capabilities. We conclude by proposing potential directions for future innovations that could address current limitations and improve the reliability and safety of IT systems. This comprehensive review provides valuable insights for researchers, engineers, and industry professionals working on electrical system safety and reliability in ungrounded networks.</div></div>","PeriodicalId":50547,"journal":{"name":"Electric Power Systems Research","volume":"242 ","pages":"Article 111464"},"PeriodicalIF":3.3,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}