Lei Han^1,*, Wanyu Ye¹, Chunfang Liu², Shihua Huang¹, Chun Chen³, Luxin Zhan³, Siyuan Liang³

Energy Engineering, Vol.122, No.12, pp. 4947-4969, 2025, DOI:10.32604/ee.2025.069040 - 27 November 2025

Abstract In contemporary medium-voltage distribution networks heavily penetrated by distributed energy resources (DERs), the harmonic components injected by power-electronic interfacing converters, together with the inherently intermittent output of renewable generation, distort the zero-sequence current and continuously reshape its frequency spectrum. As a result, single-line-to-ground (SLG) faults exhibit a pronounced, strongly non-stationary behaviour that varies with operating point, load mix and DER dispatch. Under such circumstances the performance of traditional rule-based algorithms—or methods that rely solely on steady-state frequency-domain indicators—degrades sharply, and they no longer satisfy the accuracy and universality required by practical protection systems. To overcome… More >

Jian Wang, Hui Qi, Lingyi Ji^*, Zhengya Tang, Hui Qian

Energy Engineering, Vol.122, No.11, pp. 4635-4651, 2025, DOI:10.32604/ee.2025.068667 - 27 October 2025

Abstract This paper proposes a cost-optimal energy management strategy for reconfigurable distribution networks with high penetration of renewable generation. The proposed strategy accounts for renewable generation costs, maintenance and operating expenses of energy storage systems, diesel generator operational costs, typical daily load profiles, and power balance constraints. A penalty term for power backflow is incorporated into the objective function to discourage undesirable reverse flows. The Bald Eagle Search (BES) meta-heuristic is adopted to solve the resulting constrained optimization problem. Numerical simulations under multiple load scenarios demonstrate that the proposed method effectively reduces operating cost while preventing More >

Hongsheng Su¹, Wenyao Su¹, Yulong Che^1,*, Xiping Ma², Tian Zhao¹, Limiao Ren¹

Energy Engineering, Vol.122, No.11, pp. 4777-4797, 2025, DOI:10.32604/ee.2025.068134 - 27 October 2025

Abstract Aiming at the issues of insufficient carrying capacity, limited flexibility, and weak source-network-load-storage coordination capability in distribution networks under the background of high-proportion new energy integration. This study proposes a bi-level optimization model for ADN integrating hybrid wind-solar-hydrogen-storage systems. First, an electro-hydrogen coupling system framework is constructed, including models for electrolytic hydrogen production, hydrogen storage, and fuel cells. Meanwhile, typical scenarios of wind-solar joint output are developed using Copula functions to characterize the variability of renewable energy generation. Second, a bi-level optimization model for ADN with electrolytic hydrogen production and storage systems is established: the… More >

He Wang, Shiqiang Li^*, Yiqi Liu, Jing Bian

Energy Engineering, Vol.122, No.11, pp. 4497-4521, 2025, DOI:10.32604/ee.2025.065244 - 27 October 2025

Abstract With the evolution of DC distribution networks from traditional radial topologies to more complex multi-branch structures, the number of measurement points supporting synchronous communication remains relatively limited. This poses challenges for conventional fault distance estimation methods, which are often tailored to simple topologies and are thus difficult to apply to large-scale, multi-node DC networks. To address this, a fault distance estimation method based on sparse measurement of high-frequency electrical quantities is proposed in this paper. First, a preliminary fault line identification model based on compressed sensing is constructed to effectively narrow the fault search range… More >

Qiji Dai¹, Jikai Li^2,*, Bohui Ning¹, Yutao Xu¹, Chang Liu², Xuan Zhang¹

Energy Engineering, Vol.122, No.10, pp. 4061-4080, 2025, DOI:10.32604/ee.2025.067304 - 30 September 2025

Abstract Aiming at the challenge of complex load balancing coordination for a three-phase four-leg (3P4L) based multi-ended low voltage flexible DC distribution system (M-LVDC) considering unbalanced power compensation, this paper proposes a phase-split power decoupling unbalanced compensation strategy based load balancing strategy for 3P4L based M-LVDC. Firstly, the topology and operation principle of the 3P4L-based M-LVDC system is introduced, and quasi-proportional resonant (QPR) based phase-split power current control for the 3P4L converter is proposed. Secondly, a load-balancing control strategy considering unbalanced compensation for 3P4L-based M-LVDC is presented, in which the control diagrams for each 3P4L-based converter… More >

Xin Zhang^1,*, Shixing Zhang¹, Lina Chen², Jihong Zhang¹, Peihong Yang¹, Zilei Zhang¹, Xiaoming Zhang¹

Energy Engineering, Vol.122, No.9, pp. 3647-3679, 2025, DOI:10.32604/ee.2025.067035 - 26 August 2025

Abstract A park hydrogen-doped integrated energy system (PHIES) can maximize energy utilization as a system with multiple supplies. To realize win-win cooperation between the PHIES and active distribution network (ADN), the cooperative operation problem of multi-PHIES connected to the same ADN is studied. A low-carbon hybrid game coordination strategy for multi-PHIES accessing ADN based on dynamic carbon base price is proposed in the paper. Firstly, multi-PHIES are constructed to form a PHIES alliance, including a hydrogen-doped gas turbine (HGT), hydrogen-doped gas boiler (HGB), power to gas and carbon capture system (P2G-CCS), and other equipment. Secondly, a… More > Graphic Abstract

Nisa Nacar Çıkan^*

CMES-Computer Modeling in Engineering & Sciences, Vol.143, No.3, pp. 3279-3327, 2025, DOI:10.32604/cmes.2025.065442 - 30 June 2025

Abstract This study addresses the critical challenge of reconfiguration in unbalanced power distribution networks (UPDNs), focusing on the complex 123-Bus test system. Three scenarios are investigated: (1) simultaneous power loss reduction and voltage profile improvement, (2) minimization of voltage and current unbalance indices under various operational cases, and (3) multi-objective optimization using Pareto front analysis to concurrently optimize voltage unbalance index, active power loss, and current unbalance index. Unlike previous research that oftensimplified system components, this work maintains all equipment, including capacitor banks, transformers, and voltage regulators, to ensure realistic results. The study evaluates twelve metaheuristic More >

Tareq Hamadneh¹, Belal Batiha², Frank Werner^3,*, Mehrdad Ahmadi Kamarposhti^4,*, Ilhami Colak⁵, El Manaa Barhoumi⁶

CMES-Computer Modeling in Engineering & Sciences, Vol.143, No.2, pp. 1519-1548, 2025, DOI:10.32604/cmes.2025.063571 - 30 May 2025

Abstract Reconfiguration, as well as optimal utilization of distributed generation sources and capacitor banks, are highly effective methods for reducing losses and improving the voltage profile, or in other words, the power quality in the power distribution system. Researchers have considered the use of distributed generation resources in recent years. There are numerous advantages to utilizing these resources, the most significant of which are the reduction of network losses and enhancement of voltage stability. Non-dominated Sorting Genetic Algorithm II (NSGA-II), Multi-Objective Particle Swarm Optimization (MOPSO), and Intersect Mutation Differential Evolution (IMDE) algorithms are used in this… More >

Jiran Zhu¹, Silin He¹, Chun Chen^2,*, Li Zhou², Hongqing Li¹, Di Zhang¹, Fenglin Hua¹, Tianhao Zhu²

Energy Engineering, Vol.122, No.6, pp. 2465-2483, 2025, DOI:10.32604/ee.2025.065453 - 29 May 2025

Abstract In the islanded operation of distribution networks, due to the mismatch of line impedance at the inverter output, conventional droop control leads to inaccurate power sharing according to capacity, resulting in voltage and frequency fluctuations under minor external disturbances. To address this issue, this paper introduces an enhanced scheme for power sharing and voltage-frequency control. First, to solve the power distribution problem, we propose an adaptive virtual impedance control based on multi-agent consensus, which allows for precise active and reactive power allocation without requiring feeder impedance knowledge. Moreover, a novel consensus-based voltage and frequency control More >

Huanan Yu, Chunhe Ye, Shiqiang Li^*, He Wang, Jing Bian, Jinling Li

Energy Engineering, Vol.122, No.6, pp. 2417-2448, 2025, DOI:10.32604/ee.2025.061214 - 29 May 2025

Abstract With the increasing integration of large-scale distributed energy resources into the grid, traditional distribution network optimization and dispatch methods struggle to address the challenges posed by both generation and load. Accounting for these issues, this paper proposes a multi-timescale coordinated optimization dispatch method for distribution networks. First, the probability box theory was employed to determine the uncertainty intervals of generation and load forecasts, based on which, the requirements for flexibility dispatch and capacity constraints of the grid were calculated and analyzed. Subsequently, a multi-timescale optimization framework was constructed, incorporating the generation and load forecast uncertainties. More >