Jin Lin^1,*, Bin Yu², Chao Chen¹, Jiezhen Cai¹, Yifan Wu², Cunping Wang³

Energy Engineering, Vol.123, No.1, 2026, DOI:10.32604/ee.2025.069310 - 27 December 2025

Abstract With the increasing integration of renewable energy, microgrids are increasingly facing stability challenges, primarily due to the lack of inherent inertia in inverter-dominated systems, which is traditionally provided by synchronous generators. To address this critical issue, Virtual Synchronous Generator (VSG) technology has emerged as a highly promising solution by emulating the inertia and damping characteristics of conventional synchronous generators. To enhance the operational efficiency of virtual synchronous generators (VSGs), this study employs small-signal modeling analysis, root locus methods, and synchronous generator power-angle characteristic analysis to comprehensively evaluate how virtual inertia and damping coefficients affect frequency… More > Graphic Abstract

Khairul Eahsun Fahim¹, Liyanage C. De Silva², Sk. A. Shezan^3,*, Md Ashraful Islam⁴, Md Shakib Hassan⁵, Hayati Yassin^1,*, Naveed Ahmad⁶

Energy Engineering, Vol.122, No.10, pp. 3985-3997, 2025, DOI:10.32604/ee.2025.066484 - 30 September 2025

Abstract Around the world, there has been a notable shift toward the use of renewable energy technology due to the growing demand for energy and the ongoing depletion of conventional resources, such as fossil fuels. Following this worldwide trend, Brunei’s government has initiated several strategic programs aimed at encouraging the establishment of energy from renewable sources in the nation’s energy mix. These initiatives are designed not only to support environmental sustainability but also to make energy from renewable sources increasingly competitive in comparison to more conventional energy sources like gas and oil, which have historically dominated… More >

Jingxian Ni, Chaomeng Wang, Shiqi Sun, Yuxuan Sun, Gang Ma^*

Energy Engineering, Vol.122, No.9, pp. 3719-3736, 2025, DOI:10.32604/ee.2025.066971 - 26 August 2025

Abstract To improve the fault diagnosis accuracy of a PV grid-connected inverter, a PV grid-connected inverter data diagnosis method based on MPA-VMD-PSO-BiLSTM is proposed. Firstly, unlike the traditional VMD algorithm which relies on manual experience to set parameters (e.g., noise tolerance, penalty parameter, number of decompositions), this paper achieves adaptive optimization of parameters through MPA algorithm to avoid the problem of feature information loss caused by manual parameter tuning, and adopts the improved VMD algorithm for feature extraction of DC-side voltage data signals of PV-grid-connected inverters; and then, adopts the PSO algorithm for the Then, the… More >

Moien A. Omar^*

Energy Engineering, Vol.122, No.2, pp. 561-576, 2025, DOI:10.32604/ee.2025.059352 - 31 January 2025

Abstract This research investigates the design and optimization of a photovoltaic (PV) water pumping system to address seasonal water demands across five locations with varying elevation heads. The system draws water from a deep well with a static water level of 30 m and a dynamic level of 50 m, serving agricultural and livestock needs. The objective of this study is to accurately size a PV system that balances energy generation and demand while minimizing grid dependency. Meanwhile, the study presents a comprehensive methodology to calculate flow rates, pumping power, daily energy consumption, and system capacity.… More >

Chao Zhou¹, Narisu Wang¹, Fuyin Ni^1,2,*, Wenchao Zhang¹

Energy Engineering, Vol.122, No.1, pp. 265-284, 2025, DOI:10.32604/ee.2024.057380 - 27 December 2024

Abstract Uneven power distribution, transient voltage, and frequency deviations are observed in the photovoltaic storage hybrid inverter during the switching between grid-connected and island modes. In response to these issues, this paper proposes a grid-connected/island switching control strategy for photovoltaic storage hybrid inverters based on the modified chimpanzee optimization algorithm. The proposed strategy incorporates coupling compensation and power differentiation elements based on the traditional droop control. Then, it combines the angular frequency and voltage amplitude adjustments provided by the phase-locked loop-free pre-synchronization control strategy. Precise pre-synchronization is achieved by regulating the virtual current to zero and… More >

Xin Mao^*, Hongsheng Su, Jingxiu Li

Energy Engineering, Vol.121, No.12, pp. 3929-3951, 2024, DOI:10.32604/ee.2024.057106 - 22 November 2024

Abstract The virtual synchronous generator (VSG) technology has been proposed to address the problem of system frequency and active power oscillation caused by grid-connected new energy power sources. However, the traditional voltage-current double-closed-loop control used in VSG has the disadvantages of poor disturbance immunity and insufficient dynamic response. In light of the issues above, a virtual synchronous generator voltage outer-loop control strategy based on improved linear autonomous disturbance rejection control (ILADRC) is put forth for consideration. Firstly, an improved first-order linear self-immunity control structure is established for the characteristics of the voltage outer loop; then, the… More >

Xiaohui Ye^1,*, Fucheng Tan¹, Xinli Song², Hanyang Dai², Xia Li², Shixia Mu², Shaohang Hao²

Energy Engineering, Vol.121, No.12, pp. 3689-3710, 2024, DOI:10.32604/ee.2024.055200 - 22 November 2024

Abstract Energy storage batteries can smooth the volatility of renewable energy sources. The operating conditions during power grid integration of renewable energy can affect the performance and failure risk of battery energy storage system (BESS). However, the current modeling of grid-connected BESS is overly simplistic, typically only considering state of charge (SOC) and power constraints. Detailed lithium (Li)-ion battery cell models are computationally intensive and impractical for real-time applications and may not be suitable for power grid operating conditions. Additionally, there is a lack of real-time batteries risk assessment frameworks. To address these issues, in this… More >

Cuiping Li¹, Kunqi Gao¹, Can Chen², Junhui Li^1,*, Xiaoxiao Wang², Yinchi Shao², Xingxu Zhu¹

Energy Engineering, Vol.121, No.10, pp. 2937-2959, 2024, DOI:10.32604/ee.2024.052167 - 11 September 2024

Abstract In recent years, distributed photovoltaics (DPV) has ushered in a good development situation due to the advantages of pollution-free power generation, full utilization of the ground or roof of the installation site, and balancing a large number of loads nearby. However, under the background of a large-scale DPV grid-connected to the county distribution network, an effective analysis method is needed to analyze its impact on the voltage of the distribution network in the early development stage of DPV. Therefore, a DPV orderly grid-connected method based on photovoltaics grid-connected order degree (PGOD) is proposed. This method… More >

Yue Yang¹, Jiarui Zheng¹, Long Cheng^1,*, Yongnan Zhu², Hao Wu²

Energy Engineering, Vol.121, No.3, pp. 703-728, 2024, DOI:10.32604/ee.2023.044721 - 27 February 2024

Abstract To effectively quantify the impact of distributed photovoltaic (PV) access on the distribution network, this paper proposes a comprehensive evaluation method of distributed PV grid connection combining subjective and objective combination of assignment and technique for order preference by similarity to an ideal solution (TOPSIS)—rank sum ratio (RSR) (TOPSIS-RSR) method. Based on the traditional distribution network evaluation system, a comprehensive evaluation system has been constructed. It fully considers the new development requirements of distributed PV access on the environmental friendliness and absorptive capacity of the distribution grid and comprehensively reflects the impact of distributed PV… More >

Gaber Magdy^1,2,*, Mostafa Metwally³, Adel A. Elbaset^3,4, Esam Zaki⁵

Energy Engineering, Vol.121, No.1, pp. 13-26, 2024, DOI:10.32604/ee.2023.043562 - 27 December 2023

Abstract The generation of photovoltaic (PV) solar energy is increasing continuously because it is renewable, unlimited, and clean energy. In the past, generation systems depended on non-renewable sources such as oil, coal, and gas. Therefore, this paper assesses the performance of a 51 kW PV solar power plant connected to a low-voltage grid to feed an administrative building in the 6th of October City, Egypt. The performance analysis of the considered grid-connected PV system is carried out using power system simulator for Engineering (PSS/E) software. Where the PSS/E program, monitors and uses the power analyzer that… More >