Yunzhao Wu¹, Guanglin Sha¹, Qing Duan¹, Xinwei Cong¹, Lu Liu¹, Ning Zhou², Yingjie Zhou^3,*

Energy Engineering, Vol.122, No.3, pp. 1093-1112, 2025, DOI:10.32604/ee.2025.060349 - 07 March 2025

Abstract To enhance energy interaction among low-voltage stations (LVSs) and reduce the line loss of the distribution network, a novel operation mode of the micro-pumped storage system (mPSS) has been proposed based on the common reservoir. First, some operation modes of mPSS are analyzed, which include the separated reservoir mode (SRM) and common reservoir mode (CRM). Then, based on the SRM, and CRM, an energy mutual assistance control model between LVSs has been built to optimize energy loss. Finally, in the simulation, compared to the model without pumped storage in the LVS, the SRM and CLRM… More > Graphic Abstract

Kai Shi, Dongyang Yang^*

Energy Engineering, Vol.122, No.2, pp. 471-492, 2025, DOI:10.32604/ee.2025.059651 - 31 January 2025

Abstract The rapid development of new energy power generation technology and the transformation of power electronics in the core equipment of source-grid-load drives the power system towards the “double-high” development pattern of “high proportion of renewable energy” and “high proportion of power electronic equipment”. To enhance the transient performance of AC/DC hybrid microgrid (HMG) in the context of “double-high,” a type virtual synchronous generator (-VSG) control strategy is applied to bidirectional interface converter (BIC) to address the issues of lacking inertia and poor disturbance immunity caused by the high penetration rate of power electronic equipment and… More >

Yuanxiang Luo^*, Linshu Cai, Nan Zhang

Energy Engineering, Vol.122, No.2, pp. 765-783, 2025, DOI:10.32604/ee.2024.058426 - 31 January 2025

Abstract Large-scale new energy grid connection leads to the weakening of the system frequency regulation capability, and the system frequency stability is facing unprecedented challenges. In order to solve rapid frequency fluctuation caused by new energy units, this paper proposes a new energy power system frequency regulation strategy with multiple units including the doubly-fed pumped storage unit (DFPSU). Firstly, based on the model predictive control (MPC) theory, the state space equations are established by considering the operating characteristics of the units and the dynamic behavior of the system; secondly, the proportional-differential control link is introduced to… More > Graphic Abstract

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 >

Yun Zhang^1,*, Zifen Han², Biao Tian¹, Ning Chen², Yi Fan³

Energy Engineering, Vol.122, No.1, pp. 167-184, 2025, DOI:10.32604/ee.2024.056190 - 27 December 2024

Abstract The new energy power generation is becoming increasingly important in the power system. Such as photovoltaic power generation has become a research hotspot, however, due to the characteristics of light radiation changes, photovoltaic power generation is unstable and random, resulting in a low utilization rate and directly affecting the stability of the power grid. To solve this problem, this paper proposes a coordinated control strategy for a new energy power generation system with a hybrid energy storage unit based on the lithium iron phosphate-supercapacitor hybrid energy storage unit. Firstly, the variational mode decomposition algorithm is… 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 >

Weiru Wang¹, Yulong Cao^1,*, Yanxu Wang¹, Jiale You¹, Guangnan Zhang¹, Yu Xiao²

Energy Engineering, Vol.121, No.12, pp. 3801-3823, 2024, DOI:10.32604/ee.2024.055398 - 22 November 2024

Abstract To ensure frequency stability in power systems with high wind penetration, the doubly-fed induction generator (DFIG) is often used with the frequency fast response control (FFRC) to participate in frequency response. However, a certain output power suppression amount (OPSA) is generated during frequency support, resulting in the frequency modulation (FM) capability of DFIG not being fully utilised, and the system’s unbalanced power will be increased during speed recovery, resulting in a second frequency drop (SFD) in the system. Firstly, the frequency response characteristics of the power system with DFIG containing FFRC are analysed. Then, based… More >

Mingxuan Chen¹, Jun Jia², Baoping Zhang¹, Leiyan Han³, Mengbo Ji^3,4, Zhangtao Yu¹, Dongfang Li¹, Wenyong Wang¹, Hongjing Jia¹, Huachi Xu^2,*

Energy Engineering, Vol.121, No.10, pp. 3055-3074, 2024, DOI:10.32604/ee.2024.051524 - 11 September 2024

Abstract The rise in hydrogen production powered by renewable energy is driving the field toward the adoption of systems comprising multiple alkaline water electrolyzers. These setups present various operational modes: independent operation and multi-electrolyzer parallelization, each with distinct advantages and challenges. This study introduces an innovative configuration that incorporates a mutual lye mixer among electrolyzers, establishing a weakly coupled system that combines the advantages of two modes. This approach enables efficient heat utilization for faster hot-startup and maintains heat conservation post-lye interconnection, while preserving the option for independent operation after decoupling. A specialized thermal exchange model… More >

Yuanjun Dai, Haonan Li, Baohua Li^*

Energy Engineering, Vol.121, No.6, pp. 1607-1636, 2024, DOI:10.32604/ee.2024.047255 - 21 May 2024

Abstract This paper addresses the micro wind-hydrogen coupled system, aiming to improve the power tracking capability of micro wind farms, the regulation capability of hydrogen storage systems, and to mitigate the volatility of wind power generation. A predictive control strategy for the micro wind-hydrogen coupled system is proposed based on the ultra-short-term wind power prediction, the hydrogen storage state division interval, and the daily scheduled output of wind power generation. The control strategy maximizes the power tracking capability, the regulation capability of the hydrogen storage system, and the fluctuation of the joint output of the wind-hydrogen… More >

Feng Zhao, Jinshuo Zhang^*, Xiaoqiang Chen, Ying Wang

Energy Engineering, Vol.121, No.2, pp. 339-358, 2024, DOI:10.32604/ee.2023.043082 - 25 January 2024

Abstract In the DC microgrid, the lack of inertia and damping in power electronic converters results in poor stability of DC bus voltage and low inertia of the DC microgrid during fluctuations in load and photovoltaic power. To address this issue, the application of a virtual synchronous generator (VSG) in grid-connected inverters control is referenced and proposes a control strategy called the analogous virtual synchronous generator (AVSG) control strategy for the interface DC/DC converter of the battery in the microgrid. Besides, a flexible parameter adaptive control method is introduced to further enhance the inertial behavior of… More >