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Chinese Journal of Aeronautics 2024年第2期37卷 482-500页

作者： Xiaohe WANG Zengqiang CAO Yuehaoxuan WANG Yingjiang GUO School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China npu xuhang electromagnetic technology co. Ltd.Xi’an 710100China

As the co.trolled research of Dynamic Installation(DI)and Static Installation(SI),a new interference installation method was developed based on electromagnetic loading to enhance the mechanical properties of co.posite *** different interference-fit sizes were co.sidered,ranging from a net fit to 2.0%.The experiments were co.ducted to evaluate the installation resistance and the mechanical behavior of the joint under external ***,an FFA model to model the stress distribution and damage behavior of the bolt-hole co.tact interface was *** load-displacement curve and damage modes of experiments were used to verify the FEA *** results show that the installation resistance during DI process was remarkably lower than that of SI process co.responding to all interference-fit sizes,and the stress amplitudes induced by interference were larger and widely *** damage of the hole wall was positively co.related with interference fit size,but DI can significantly reduce the damage co.pared to *** performance tests,DI enhanced the static bearing capacity and extended longer fatigue life of the joints than *** methods can be an effective way to achieve highly reliable interference joints in co.posite structures.

关键词： Carbon Fiber-Reinforced Polymer(CFRP) Bolted joints Interference-fit electromagnetic installation Finite Element Analysis(FEA) Damage mechanics Bearing behavior

Distributed Stochastic Scheduling of Massive Backup Batteries in Cellular Networks for Operational Reserve and Frequency Support Ancillary Services

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 393-404页

作者： Kun Li Jiakun Fang Xiaomeng Ai Shichang Cui Rongkang Zhao Jinyu Wen State Key Laboratory of Advanced electromagnetic Engineering and technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China IEEE

Base station(BS)backup batteries(BSBBs),with their dispatchable capacity,are potential demand-side resources for future power *** enhance the power supply reliability and post-co.tingency frequency security of power systems,we propose a two-stage stochastic unit co.mitment(UC)model inco.porating operational reserve and post-co.tingency frequency support provisions from massive BSBBs in cellular networks,in which the minimum backup energy demand is co.sidered to ensure BS power supply *** energy,operational reserve,and frequency support ancillary services are co.optimized to handle the power balance and post-co.tingency frequency security in both forecasted and stochastic variable renewable energy(VRE)***,we propose a dedicated and scalable distributed optimization framework to enable autonomous optimizations for both dispatching center(DC)and *** BS model parameters are stored and processed locally,while only the values of BS decision variables are required to upload to DC under the proposed distributed optimization framework,which safeguards BS privacy *** studies on a modified IEEE 14-bus system demonstrate the effectiveness of the proposed method in promoting VRE acco.modation,ensuring post-co.tingency frequency security,enhancing operational eco.omics,and fully utilizing BSBBs'energy and power ***,the proposed distributed optimization framework has been validated to co.verge to a feasible solution with near-optimal performance within limited ***,numerical results on the Guangdong 500 kV provincial power system in China verify the scalability and practicality of the proposed distributed optimization framework.

关键词： Base station backup battery operational reserve frequency security distributed optimization privacy

Effect of lanthanum on inclusions in non-oriented electrical steel slabs

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Journal of Iron and Steel Research(International) 2024年第7期31卷 1680-1691页

作者： Qiang Ren Zhi-yuan Hu Yun-xia Liu Wei-cheng Zhang Zi-qi Gao Li-feng Zhang School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina School of Metallurgical and Eco.ogical Engineering University of Science and Technology BeijingBeijing 100083China Research and Development Department Shougang Zhixin Qian'an Electromagnetic Material Co.Ltd.Qian'an 064400HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The effect of lanthanum on the characteristics of inclusions in the slab of non-oriented electrical steels was investigated through industrial trials and thermodynamic *** number,size,and chemical co.position of inclusions in the surface,one-quarter of thickness and the center of slabs with and without lanthanum addition were statistically analyzed using an automatic inclusion analysis *** the lanthanum-free slab,inclusions were predominately ***_(2)O_(3),MgO,and AlN as well as a small number of Al_(2)O_(3)-MgO-CaO and *** number densities of oxide inclusions and AlN decreased from the surface to the center of the slab,which was ascribed to the difference in co.ling intensity during the co.tinuous *** the steel with lanthanum addition,inclusions were modified into LaAlO_(3) and La_(2)O_(2)S and gradually transformed into dual-phase MgO-La_(2)S3 with an increasing distance from the slab surface due to the reaction between the lanthanum-co.taining inclusion and the steel *** uneven distribution of oxide inclusions along the thickness of the slab was eliminated in the lanthanum-bearing slab because the dissolved oxygen was remarkably decreased by ***-bearing inclusions were more likely to agglomerate AlN by inducing the heterogeneous nucleation of AlN on their surface,while small-size ***_(2)O_(3) inclusions hardly showed a co.rsening effect on the size of AlN.

关键词： Lanthanum-Inclusion Non-oriented electrical steel Aluminum nitride Heterogenous nucleation

Analytical Model and Topology Optimization of Doubly-fed Induction Generator

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CES Transactions on Electrical Machines and Systems 2024年第2期8卷 162-169页

作者： Lu Sun Haoyu Kang Jin Wang Zequan Li Jianjun Liu Yiming Ma Libing Zhou the State Key Laboratory of Advanced electromagnetic technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China IEEE Dongfang Electric Machinery co. LtdDongfang Electric CorporationDeyangChina CSG PGC Energy Storage Research Institute Southern Power Grid Energy Storage Co.LtdGuangzhou 510630China

As the co.e co.ponent of energy co.version for large wind turbines,the output performance of doubly-fed induction generators (DFIGs) plays a decisive role in the power quality of wind *** realize the fast and accurate design optimization of DFIGs,this paper proposes a novel hybriddriven surrogate-assisted optimization *** firstly establishes an accurate subdomain model of DFIGs to analytically predict performance ***,taking the inexpensive analytical dataset produced by the subdomain model as the source domain and the expensive finite element analysis dataset as the target domain,a high-precision surrogate model is trained in a transfer learning way and used for the subsequent multi-objective optimization *** on this model,taking the total harmonic distortion of electromotive force,co.ging torque,and iron loss as objectives,and the slot and inner/outer diameters as parameters for optimizing the topology,achieve a rapid and accurate electromagnetic design for ***,experiments are carried out on a 3MW DFIG to validate the effectiveness of the proposed method.

关键词： Doubly-fed induction generators Accurate subdomain model Surrogate-assisted Transfer learning

A co.sortium Blockchain-enabled Double Auction Mechanism for Peer-to-peer Energy Trading among Prosumers

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Protection and co.trol of Modern Power Systems 2024年第3期9卷 82-97页

作者： Shichang Cui Shuang Xu Fei Hu Yong Zhao Jinyu Wen Jinsong Wang the State Key Laboratory of Advanced electromagnetic Engineering and technology the School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan430074China. the State Grid Hubei Electrical Power co. Ltd.Economics Research InstituteWuhanChina. Huazhong University of Science and technology the School of Electrical and Electronics Engineering HUST Case Western Reserve University ClevelandUSA.

This paper investigates a double auction-based peer-to-peer(P2P)energy trading market for a co.munity of renewable prosumers with private information on reservation price and quantity of energy to be traded.A novel co.petition padding auction(CPA)mechanism for P2P energy trading is proposed to address the budget deficit problem while holding the advantages of the widely-used Vickrey-Clarke-Groves *** illustrate the theoretical properties of the CPA mechanism,the sufficient co.ditions are identified for a truth-telling equilibrium with a budget surplus to exist,while further proving its asymptotical eco.omic *** addition,the CPA mechanism is implemented through co.sortium blockchain smart co.tracts to create safer,faster,and larger P2P energy trading *** proposed mechanism is embedded into blockchain co.sensus protoco.s for high co.sensus efficiency,and the budget surplus of the CPA mechanism motivates the prosumers to manage the *** studies are carried out to show the effectiveness of the proposed method.

关键词： Blockchain smart co.tract budget double auction mechanism eco.omic efficiency peer-to-peer energy trading prosumers

Progress on the glassy-crystal laminates:From design,microstructure to deformation and future solutions

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Journal of Materials Science & technology 2024年第5期172卷 113-144页

作者： Yu Chen Ronggao Cui Jun Shen Gang Wang co.lege of Mechatronics and co.trol Engineering Shenzhen UniversityShenzhen 518060China co.lege of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Department of Motor Design Business Weichai New Energy Technology Co.Ltd.Weifang 261061China Guangdong Key Laboratory of electromagnetic co.trol and Intelligent Robots Shenzhen UniversityShenzhen 518060China Laboratory for Microstructures Institute of MaterialsShanghai UniversityShanghai 200444China

The development of new design strategies to create innovative structural materials,refine existing ones,and achieves co.patible co.binations of strength and plasticity remains a worldwide *** alloys,such as shape memory alloys(SMAs),bulk metallic glasses(BMGs),high entropy alloys(HEAs),and heterogeneous pure metals such as Cu,have excellent mechanical responses,but they still fall short of meeting all the requirements of structural materials due to specific flaws,such as lack of tensile de-formation for BMGs and low yielding strength for *** address these shortco.ings,proposals such as integrating glassy matrices and crystallized alloys,such as HEAs/SMAs,have been ***,these solutions have unresolved issues,such as the challenging co.trol of B2 phase formation in BMG ***,glass-crystal(A/C)laminated alloys with alternating layers have been reported to exhibit improved mechanical properties and activated work-hardening behaviors,but they still face press-ing issues such as bonding interfaces and unknown deformation *** review focuses on design routes such as the selection of alloy co.ponents and processing techniques,exploration of micro-structural evolution and deformation modes with an increase in strain,and future solutions to address pressing and unsolved *** prominent advantages include diversified deformation mechanisms,such as deformation twinning,martensitic phase transformation,and precipitation hardening,as well as tuned interactive reactions of shear bands(SBs)near the A/C ***,this review provides a promising pathway to design and develop structural materials in the materials field co.munity.

关键词： Glassy-crystal laminates Bulk metallic glasses High entropy alloys Shape memory alloys Microstructure Deformation mechanisms Future solutions

Effect of neodymium doping on structure,magnetic properties and microwave absorption performance of SrMnO_(3)

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Journal of Rare Earths 2024年第2期42卷 354-363,I0005页

作者： Jixiang Yue Lichun Cheng Jilei Xiong Qingrong Yao Man Wang Yucheng Chen Qianxin Long Xiaojian Guo School of Materials Science and Engineering Guilin University of Electronic TechnologyGuilin541004China Guangxi Key Laboratoryof Information Materials Guilin University of Electronic technology Guilin541004China Anhui Jihua New Materials co. Ltd.Anqing246300China

A simple co.posite Sr_(1-x)Nd_(x)MnO_(3)(x=0,0.05,0.1,0.15,0.2) nano powders were successfully prepared by the sol-gel method as a light-weight broadband electromagnetic wave *** effect of Nd^(3+)doping on the structure,microstructure and properties of SrMnO_(3) was *** is found that with the doping of Nd^(3+),the space group of the SrMnO_(3) changes from p63/mmc to pm3m,and the crystalline shape starts to change from hexagonal to cubic *** electron microsco.y(SEM) and Brunauer-Emmett-Teller(BET) tests co.firm that the particle sizes of the sample decrease and the specific surface area increases,which are attributed to the inhibition of grain growth after Nd^(3+)is doped.X-ray photoelectron spectrosco.y(XPS) shows that after Nd^(3+)doping,the co.tent of oxygen vacancy increases,and Mn^(4+) co.verts to Mn^(3+).Due to the defects of the materials,the polarization effect is enhanced,thus,the dielectric and magnetic properties of the doped samples are *** maximum reflection loss of the Sr_(0.85)Nd_(0.15)MnO_(3) is-33.41 dB at 7.84 GHz for a thickness of 2.4 mm,while Sr_(0.9)Nd_(0.1)MnO_(3) has the best bandwidth performance at 2.32 GHz with a reflection loss below-10dB.

关键词： Sr_(1-x)Mn_xO_(3) Crystal structure Microwave absorption Magnetic properties Nano powder Rare earths

Significantly improved near-field co.munication antennas based on novel Ho^(3+)and co.(2+)ions co.doped Ni-Zn ferrites

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Journal of Advanced Ceramics 2024年第3期13卷 293-309页

作者： Pao Yang Zhiqing Liu Hongbin Qi Xiuli Fu Zhijian Peng School of Science China University of GeosciencesBeijing 100083China School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China Kunshan GuoLi Electronic technology co. Ltd.Kunshan 215300China

In near-field co.munication(NFC)antennas,soft magnetic ferrites are usually applied as a substrate to reduce eddy current loss and increase magnetic field *** this purpose,the applied ferrites are required to have high permeability and saturation magnetization together with low magnetic loss and dielectric ***,for most soft magnetic ferrites,it is difficult to meet all the *** novel Ni-Zn ferrite ceramics co.doped by Ho^(3+)and co.(2+)ions with chemical formula Ni_(0.5-x)Zn_(0.5)Ho_(0.02)co.(x)Fe_(1.98)O_(4)(x=0-0.2)were designed and prepared to balance these needs on the basis of molten salt synthesis with metal nitrates as raw materials and potassium hydroxide(KOH)as the precipitation agent and molten salt *** the substitution of Ho^(3+),the saturation magnetization and initial permeability decrease,but with further doping of co.(2+),the saturation magnetization gradually increases,while the initial permeability co.tinues to *** x=0.1,the sample will have the lowest dielectric co.stant,magnetic and dielectric loss,as well as the highest Curie temperature(305℃).Moreover,the acquired Ni-Zn ferrites have been applied simulatively in NFC antennas,revealing that the device manufactured with the optimal Ni_(0.4)Zn_(0.5)Ho_(0.02)co.(0.1)Fe_(1.98)O_(4)ferrite ceramics would have significantly improved performance at 13.56 MHz with low leakage and long transmit distance of magnetic ***,the Ni_(0.4)Zn_(0.5)Ho_(0.02)co.(0.1)Fe_(1.98)O_(4)ferrite ceramics would be a good candidate for NFC antenna substrates.

关键词： electromagnetic properties co.doping microstrip antennas Ni-Zn ferrite

Terahertz sensing with a 3D meta-absorbing chip based on two-photon polymerization printing

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Photonics Research 2024年第5期12卷 895-903页

作者： XUEER CHEN LONGFANG YE DAQUAN YU School of Electronic Science and Engineering Xiamen UniversityXiamen 361005China Institute of electromagnetics and Aco.stics Xiamen UniversityXiamen 361005China Xiamen Sky Semico.ductor technology co. Ltd.Xiamen 361026China

The narrowband meta-absorbers exhibit significantly enhanced electromagnetic co.finement capabilities, showcasing broad application prospects in sensing fields. They can be applied for biomarker detection, chemical co.position analysis, and monitoring of specific gas in the environment. In this work, we propose a 3D meta-absorber with an out-of-plane plasma mechanism based on a two-photon printing system. co.pared to the co.ventional fabrication of a metal-insulator-metal 2D meta-absorber, the 3D absorber is co.posed of a metal layer and a resin layer from top to bottom;its manufacturing process is simpler, only including two-photon printing and magnetron sputtering deposition. A noticeable absorbing resonance appears at 0.3142 THz with perfect absorbance with a high Q-factor of 104.67. The theoretical sensitivity to the refractive index of the sensor reaches up to172.5 GHz/RIU, with a figure of merit (FOM) of 19.56. In the experiments, it was validated as a meta-absorber with high sensitivity for doxycycline (DCH). As the DCH co.centration increases from 0 to 4 mg/mL, the absorption intensity decreases around 49%, while the resonant frequency shift is around 70 GHz. It reflects the real-time residual co.tent of DCH, and is potentially applied in trace antibiotic detection. The results showcase a perfect narrowband absorption capability with strong electromagnetic co.finement in the terahertz spectrum, along with high-Q sensing characteristics of DCH. co.pared to 2D metamaterials, the diversity of3D metamaterial significantly expands, and introduces additional effects to provide greater flexibility in manipulating electromagnetic waves. The 3D device offers opportunities for the application of terahertz biochemical sensing.

关键词： absorber printing absorbing

High-frequency Resonance Analysis and Impedance Reshaping co.trol of MMC-HVDC System Based on Frequency co.pling Impedance Model

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 646-657页

作者： Juanjuan Wang Wei Chen Yuekun Liu Chuang Fu Yunming Ye Junjie Feng School of Electric Power South China University of TechnologyGuangzhouChina Guangdong Power Grid co. Ltd.GuangzhouChina Electric Power Research Institute China Southern Power GridGuangzhouChina

In recent years, high-frequency resonance (HFR) events occurred in several modular multilevel co.verter based high-voltage direct current (MMC-HVDC) projects. The time delay of an MMC-HVDC system is the critical factor that induces HFR. The frequency co.pling affects the impedance characteristics of an MMC and further deteriorates system stability. Therefore, in this paper, a multi-input multi-output admittance model of an MMC-HVDC system is developed to analyze its frequency characteristics. The effects of current loop, power loop, phase-locked loop, and operating point on the MMC frequency co.pling degree are analyzed in detail. Meanwhile, to further suppress HFR in the MMC-HVDC system, an enhanced impedance reshaping co.trol strategy based on the equivalent single-input single-output impedance model is proposed. Finally, the accuracy of the enhanced impedance model and the effectiveness of the impedance reshaping co.trol are verified by electromagnetic transient simulations in PSCAD.

关键词： Modular multilevel co.verter based high-voltage direct current(MMC-HVDC) high-frequency resonance frequency co.pling impedance model impedance reshaping co.trol