Dongfang Huang^1,4, Peng Lv^1,2,3,4,*, Changlin Zhong^1,2, Xingsheng Zhou^1,2, Zhichen Liu⁴

Journal of Renewable Materials, Vol.11, No.3, pp. 1383-1400, 2023, DOI:10.32604/jrm.2022.023261

Abstract In this work, the microstructure, hydrogen storage properties, anti-oxide ability and rate limiting step of Zr(Cr_1−xCo_x)₂ (x = 0, 0.2, 0.4 and 0.6) alloys have been investigated. After studying the crystal structure, we found that all alloy samples could show C14-type phase but the alloy sample x = 0 could also show a small amount of Cr phase. Rietveld fitting showed that lattice parameter and unit cell volume of C14-type phase decreased with increasing x. After further research, it was clear that the first hydrogen absorption capacity decreased with increasing x. But introducing more Co content had a positive influence on the effective hydrogen… More >

Billel Meghni¹, Afaf Benamor², Oussama Hachana³, Ahmad Taher Azar^4,5,*, Amira Boulmaiz⁶, Salah Saad¹, El-Sayed M. El-kenawy^7,8, Nashwa Ahmad Kamal⁹, Suliman Mohamed Fati⁵, Naglaa K. Bahgaat¹⁰

CMC-Computers, Materials & Continua, Vol.74, No.2, pp. 3977-3996, 2023, DOI:10.32604/cmc.2023.029838

Abstract The integration of wind turbines (WTs) in variable speed drive systems belongs to the main factors causing low stability in electrical networks. Therefore, in order to avoid this issue, WTs hybridization with a storage system is a mandatory. This paper investigates WT system operating at variable speed. The system contains of a permanent magnet synchronous generator (PMSG) supported by a battery storage system (BSS). To enhance the quality of active and reactive power injected into the network, direct power control (DPC) scheme utilizing space-vector modulation (SVM) technique based on proportional-integral (PI) control is proposed. Meanwhile, to improve the rendition of… More >

Saeed Akbari¹, Seyed Saeed Fazel^1,*, Hamed Hashemi-Dezaki^2,3

Energy Engineering, Vol.120, No.1, pp. 69-86, 2023, DOI:10.32604/ee.2022.024121

Abstract The networking of microgrids has received significant attention in the form of a smart grid. In this paper, a set of smart railway stations, which is assumed as microgrids, is connected together. It has been tried to manage the energy exchanged between the networked microgrids to reduce received energy from the utility grid. Also, the operational costs of stations under various conditions decrease by applying the proposed method. The smart railway stations are studied in the presence of photovoltaic (PV) units, energy storage systems (ESSs), and regenerative braking strategies. Studying regenerative braking is one of the essential contributions. Moreover, the… More > Graphic Abstract

Tinnawat Hongphan¹, Matthew O. T. Cole^1,*, Chakkapong Chamroon¹, Ziv Brand²

Energy Engineering, Vol.120, No.1, pp. 147-161, 2023, DOI:10.32604/ee.2022.022821

Abstract This paper presents a theoretical and experimental study on controller design for the AMBs in a small-scale flywheel energy storage system, where the main goals are to achieve low energy consumption and improved rotordynamic stability. A H-infinity optimal control synthesis procedure is defined for the permanent-magnet-biased AMB-rotor system with 4 degrees of freedom. Through the choice of design weighting functions, notch filter characteristics are incorporated within the controller to reduce AMB current components caused by rotor vibration at the synchronous frequency and higher harmonics. Experimental tests are used to validate the controller design methodology and provide comparative results on performance… More >

Jun Zhou^1,*, Shijie Fang¹, Jinghong Peng¹, Qing Li², Guangchuan Liang^1,*

Energy Engineering, Vol.120, No.1, pp. 221-243, 2023, DOI:10.32604/ee.2022.020317

Abstract Underground energy storage is an important function of all energy supply systems, and especially concerning the seemingly eternal imbalance between production and demand. Salt rock underground energy storage, for one, is widely applied in both traditional and renewable energy fields; and this particular technique can be used to store natural gas, hydrogen, and compressed air. However, resource diversification and structural complexity make the supply system increasingly uncertain with the passing years, leading to great challenges for energy storage facilities in the present, and perhaps going into the future as well. Hence, it is necessary to research the operation stability of… More >

Lihu Cao^1,2, Jinsheng Sun^1,*, Bo Zhang^3,*, Nu Lu⁴, Yuqiang Xu¹

Energy Engineering, Vol.120, No.1, pp. 35-48, 2023, DOI:10.32604/ee.2022.022867

Abstract In gas storage or high-pressure gas wells, annular pressure is an unavoidable threat to safe, long-term resource production. The more complex situation, however, is multiple annular pressure, which means annular pressure happens in not only one annulus but two or more. Such a situation brings serious challenges to the identification of well integrity. However, few researches analyze the phenomenon of multiple annular pressure. Therefore, this paper studies the mechanism of multi-annular pressure to provide a foundation for its prevention and diagnosis. Firstly, the multi-annular pressure is classified according to the mechanism and field data. Then the failure mechanism and function… More >

Yifei Xiao, Shijie Zhou^*

CMES-Computer Modeling in Engineering & Sciences, Vol.135, No.1, pp. 169-185, 2023, DOI:10.32604/cmes.2022.021795

Abstract To achieve the high availability of health data in erasure-coded cloud storage systems, the data update performance in erasure coding should be continuously optimized. However, the data update performance is often bottlenecked by the constrained cross-rack bandwidth. Various techniques have been proposed in the literature to improve network bandwidth efficiency, including delta transmission, relay, and batch update. These techniques were largely proposed individually previously, and in this work, we seek to use them jointly. To mitigate the cross-rack update traffic, we propose DXR-DU which builds on four valuable techniques: (i) delta transmission, (ii) XOR-based data update, (iii) relay, and (iv)… More >

Chongyang Nie, Fankai Kong^*, Huaqiu Ding, Hongli Pan

CMES-Computer Modeling in Engineering & Sciences, Vol.135, No.1, pp. 483-510, 2023, DOI:10.32604/cmes.2022.021083

Abstract The different folding and storage forms of an inflatable boarding platform will have a direct impact on the deployment effect of the marine emergency evacuation system. This paper proposes different folding and storage methods for an inflatable boarding platform in a marine emergency evacuation system. According to the difference between the fold line and the fold direction, the numerical models of a boarding platform with partial fold, “Z” type fold and inner spiral fold are established. The platform models with three folding modes are simulated by numerical simulation. According to the numerical results of the inflation process, the displacement changes… More > Graphic Abstract

Pan Zhang, Lingling Xu^*, Xin Shi, Zemeng Guo, Jiajia Cheng

Journal of Renewable Materials, Vol.11, No.2, pp. 689-705, 2023, DOI:10.32604/jrm.2022.022232

Abstract Cold chain transportation is currently a hot research topic. Since the traditional refrigeration methods lead to the consumption of large amounts of energy, the search for new energy storage materials is a major trend. In the present contribution, n-dodecane/PMMA microencapsulated phase change materials were prepared by suspension polymerization for ice-temperature cold chain transportation and their preparation parameters were explored using the encapsulation ratio as optimization indicator. The results show that the n-dodecane-containing microcapsules have a maximum encapsulation ratio of 93.2% when using a core-to-wall ratio of 3:1, 5% of emulsifier, 30% of crosslinker, and 2000 rpm of emulsification speed. The phase… More >

Liang Luo¹, Xingmei Li¹, Kaijiang Yang¹, Mengyang Wei¹, Jiong Chen¹, Junqian Yang¹, Liang Yao^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.134, No.3, pp. 1565-1595, 2023, DOI:10.32604/cmes.2022.021198

Abstract The emergence of power dispatching automation systems has greatly improved the efficiency of power industry operations and promoted the rapid development of the power industry. However, with the convergence and increase in power data flow, the data dispatching network and the main station dispatching automation system have encountered substantial pressure. Therefore, the method of online data resolution and rapid problem identification of dispatching automation systems has been widely investigated. In this paper, we perform a comprehensive review of automated dispatching of massive dispatching data from the perspective of intelligent identification, discuss unresolved research issues and outline future directions in this… More >