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An improved initial rotor position estimation method using high-frequency pulsating voltage injection for PMSM

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Defence Technology（防务技术） 2024年第3期33卷 19-29页

作者： Yang Jiang Ming Cheng school of Electrical engineering Southeast UniversityNanjing 210096China

High frequency pulsating voltage injection method is a good candidate for detecting the initial rotor position of permanent magnet synchronous ***,traditional methods require a large number of filters,which leads to the deterioration of system stability and dynamic *** order to solve these problems,a new signal demodulation method is proposed in this *** proposed new method can directly obtain the amplitude of high-frequency current,thus eliminating the use of filters,improving system stability and dynamic performance and saving the work of adjusting filter *** addition,a new magnetic polarity detection method is proposed,which is robust to current measurement ***,experiments verify the effectiveness of the method.

关键词： Initial position detection Signal demodulation algorithm Magnetic polarity detection Filter elimination

Deterministic and Robust Volt-var Control Methods of Power System Based on Convex Deep Learning

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 719-729页

作者： Qing Ma Changhong Deng the school of Electrical engineering and Automation Wuhan UniversityWuhanChina

Volt-var control(VVC)is essentially a non-convex optimization problem due to the non-convexity of power flow(PF)constraints,resulting in the difficulty in obtaining the optimum without convexity *** existing second-order cone method for the convexity conversion often leads to a sharp increase in PF constraints and optimization variables,which in turn increases the optimization difficulty or even leads to optimization *** paper first proposes a deterministic VVC method based on convex deep learning power flow(DLPF).This method uses the input convex neural network(ICNN)to establish a single convex mapping between state parameters and node voltage to complete the convexity conversion while the optimization variables only correspond to reactive power equipment,which can ensure the global optimum with extremely fast computation *** cope with the impact brought by the uncertainty of distributed energy and omit the additional worst scenario search of traditional robust VVC,this paper proposes robust VVC method based on convex deep learning interval power flow(DLIPF),which continues to adopt ICNN to establish another convex mapping between state parameters and node voltage *** DLIPF with DLPF,this method decreases the modeling and optimization difficulty of robust VVC *** results on 30-bus,118-bus,and 200-bus systems prove the correctness and rapidity of the proposed methods.

关键词： Volt-var control convexity conversion convex deep learning power flow

A novel three-inflection-point sliding mode control framework for forward-tilting morphing aerospace vehicle with performance constraints and actuator faults

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Chinese Journal of Aeronautics 2024年第8期37卷 293-310页

作者： Xinkai LI Lei DOU Hongli ZHANG Yue MENG school of Electrical engineering Xinjiang UniversityUrumqi 830047China

A prescribed performance control scheme based on the three-inflection-point hyperbolic function and predefined time performance function is proposed to solve the trajectory tracking problem of the forward-tilting morphing aerospace vehicle with time-varying actuator *** accurately estimate the loss degree of actuator faults,an immersion and invariance observer based on the predefined time dynamic scale factor is designed to estimate and compensate it.A composite dynamic sliding mode surface is designed using a three-inflection-point hyperbolic function,and a novel three-inflection-point sliding mode control framework is *** convergent domain of the sliding manifold is adjusted by parameters,and the system error convergence is controllable.A transfer function is designed to eliminate the sensitivity of the three-inflection-point hyperbolic sliding mode to the unknown initial state,and combined with the barrier Lyapunov function,and the performance constraint of the system is *** global asymptotic stability of the system is demonstrated using a strict mathematical *** effectiveness and superiority of the proposed control scheme are proven by simulation experiments.

关键词： Morphing aerospace vehicle Actuator faults Immersion and invariance Three-inflection-point sliding mode control Prescribed performance control

Preparation of PrFe_(x)Co_(1-x)O_(3)/Mt catalyst and study on degradation of 2-hydroxybenzoic acid wastewater by catalytic wet peroxide oxidation

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Chinese Journal of Chemical engineering 2024年第1期65卷 286-297页

作者： Binxia Zhao Yijia Gao Tiancheng Hun Xiaoxiao Fan Nan Shao Xiaoqian Chen school of Chemical engineering Northwest UniversityXi'an 710069China

In this study,the perovskite nanocomposite PrFe_(x)Co_(1-x)O_(3)(Pr(S))was successfully synthesized by the sol-gel method;PrFe_(x)Co_(1-x)O_(3)/Al-pillared montmorillonite(Pr(S)/Mt)catalysts were prepared by impregnation(D)method and solid-melting(G)method,respectively,with Pr(S)as the active component and Al-pillared montmorillonite as the *** catalysts were applied to treat the 2-hydroxybenzoic acid(2-HA)-simulated wastewater by catalytic wet peroxide oxidation(CWPO)technique,and the chemical oxygen demand(COD)removal rate and the 2-HA degradation rate were used as indicators to evaluate the catalytic *** results of the experiment indicated that the solid-melting method was more conducive to preparing the catalyst when the Co/Fe molar ratio of 7:3 and the optimal structural properties of the catalysts were *** influence of operating parameters,including reaction temperature,catalyst dosage,H_(2)O_(2)dosage,pH,and initial 2-HA concentration,were optimized for the degradation of 2-HA by *** results showed that 97.64%of 2-HA degradation and 75.23%of COD removal rate were achieved under more suitable experimental *** addition,after the catalyst was used five times,the degradation rate of 2-HA could still reach 76.93%,which implied the high stability and reusability of the *** high catalytic activity of the catalyst was due to the doping of Co into PrFeO_(3),which could promote the generation of HO·,and the high stability could be attributed to the loading of Pr(S)onto Al-Mt,which reduced the leaching of reactive *** study of reaction mechanism and kinetics showed that the whole degradation process conformed to the pseudo-firstorder kinetic equation,and the Langmuir-Hinshelwood method was applied to demonstrate that catalysis was dominant in the degradation process.

关键词： Montmorillonite Perovskite Catalytic wet peroxide oxidation(CWPO) 2-Hydroxybenzoic acid

In Situ Coupling of Highly Dispersed Ni/Fe Metal-NC Sites and N-Doped 3D Carbon Fibers Toward Free-Standing Bifunctional Cathode for Flexible Zinc-Air Battery

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Energy & Environmental Materials 2024年第1期7卷 125-134页

作者： Chenglong Lai Mengjun Li Yi Shen Min Zhou Wei Wang Kai Jiang Haomiao Li Kangli Wang State Key Laboratory of Advanced Electromagnetic engineering and Technology School of Electrical and Electronic Engineering Huazhong University of Science and Technology school of Materials Science and engineering Huazhong University of Science and Technology engineering Research Center of Power Safety and Efficiency Ministry of Education

Designing flexible free-standing air-electrode with efficient OER/ORR performance is of vital importance for the application of Zinc-air batteries in flexible ***,a flexible free-standing electrode(Ni/Fe-NC/NCF/CC) is synthesized by in-situ coupling of binary Ni/Fe-NC nanocubes and N-doped carbon nanofibers(NCF) rooted on carbon cloth.

关键词： binary Ni/Fe-NC sites in-situ coupling synergistic catalytic effect Zn-air battery

MoS2 as a cocatalyst applied in advanced oxidation processes for enhancing degradation of organic pollutants: a review

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Tungsten 2024年第3期6卷 473-487页

作者： Ming-Hao Fan Cong-Hui Wang Xiang Yu Jun Ding Ao-Qi Xiao Yue Li Wei-Ya Huang school of Material Science and engineering Henan Polytechnic University school of Chemical and Printing-Dyeing engineering Henan International Joint Laboratory of Rare Earth Composite Materials Henan University of Engineering school of Chemistry and Chemical engineering Jiangxi University of Science and Technology Department of Chemical and Environmental engineering University of Cincinnati

Fenton technology,as a typical advanced oxidation processes（AOPs）,can generate reactive oxygen species（ROS） of strong oxidation capacity to degrade organic pollutants,which has attracted wide ***,it is accompanied by the slow Fe3+/Fe2+cycle rate,easy to generate iron sludge and so ***,it has been proven that the inorganic cocatalysts represented by MoS2can effectively solve the above ***,MoS2can accelerate the activation of peroxy mono sulfate（PMS） and peroxodisulfate（PDS） by Fe2+.In this paper,MoS2as the cocatalyst in H2O2+Fe2+,PMS+Fe2+and PDS+Fe2+were comprehensively ***,the cycling processes of Fe3+/Fe2+in different systems,the cocatalytic effect of MoS2by the exposed active sites,the ROS generation mechanism as well as the microscopic mechanism during the reaction were elaborated *** results indicate that the reductive active sites on the surface of MoS2can promote the regeneration of Fe2+through the cycle between Fe3+/Fe2+and Mo4+/Mo5+/Mo6+.Thus,ROS such as ·OH,SO4·-and1O2with strong oxidizing property can be produced to improve the degradation efficiency of organic *** last,the challenges and developments of MoS2cocatalysts in AOPs for practical applications were *** review contributes to a deeper understanding of the cocatalytic effect of two-dimensional metal sulfides in AOPs and facilitates their industrial application.

关键词： Cocatalyst Fenton reaction Degradation of organic pollutant Molybdenum disufide Reactive oxygen species

Numerical study of steady flow characteristics of a rear variable-area bypass injector with alternating area regulator

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Chinese Journal of Aeronautics 2024年第5期37卷 180-198页

作者： Runfu LIU Zhenyao LI Huiliu ZHANG Qixing WANG Yue HUANG Yancheng YOU school of Aerospace engineering Xiamen UniversityXiamen 361000China

The mixing effectiveness of the airflow between the inner and outer bypass inlets of a Rear Variable-Area Bypass Injector(RVABI)is the key to the afterburner performance of variable cycle *** paper describes an optimized RVABI design based on an alternating area regulator to improve the velocity/temperature uniformity of the incoming flow at the *** with a classical RVABI,numerical simulations show that the proposed alternating RVABI performs better in terms of thermal mixing efficiency and total pressure loss in different variable cycle engine *** the increasing air contact area between the inner and outer bypass of alternating structure RVABI,and a larger streamwise vortex in the inner bypass inlet due to the proposed alternating lobe structure in the RVABI contribute to the significantly increase of mixing ***,the alternating regulator induces strong streamwise vortex,which helps to improve the airflow mixing with its vortex-induced *** interaction between the streamwise vortex and azimuthal vortex further promises the velocity/temperature uniformity after the *** the increase of alternating lobe’s height ratio,the covering area of the streamwise vortex and the azimuthal vortex is enlarged,which further enhances the thermal mixing efficiency of the *** design gives an insight into the future design and optimization of RVABI.

关键词： Alternating area regulator Lobed mixer Variable cycle engine Rear Variable-Area Bypass Injector(RVABI) Streamwise vortex

Formatted PVDF in lamellar composite solid electrolyte for solidstate lithium metal battery

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Nano Research 2024年第6期17卷 5159-5167页

作者： Xinji Zhang Yafang Zhang Shiyue Zhou Jingchuan Dang Chenye Wang Wenjia Wu Jingtao Wang school of Chemical engineering Zhengzhou UniversityZhengzhou 450001China

Solid polymer electrolytes(SPEs)hold great application potential for solid-state lithium metal battery because of the excellent interfacial contact and processibility,but being hampered by the poor room-temperature conductivity(~10^(−7)S·cm^(−1))and low lithium-ion transference number(tLi+).Here,a lamellar composite solid electrolyte(Vr-NH_(2)@polyvinylidene fluoride(PVDF)LCSE)withβ-conformation PVDF is fabricated by confining PVDF in the interlayer channel of-NH_(2)modified vermiculite lamellar *** demonstrate that the conformation of PVDF can be manipulated by the nanoconfinement effect and the interaction from channel *** presence of-NH_(2)groups could induce the formation ofβ-conformation PVDF through electrostatic interaction,which serves as continuous and rapid lithium-ion transfer *** a result,a high room-temperature ionic conductivity of 1.77×10^(−4)S·cm^(−1)is achieved,1-2 orders of magnitude higher than most ***,Vr-NH_(2)@PVDF LCSE shows a high tLi+of 0.68 because of the high dielectric constant,~3 times of that of PVDF SPE,and surpassing most of reported *** LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)||Li cell assembled by Vr-NH_(2)@PVDF LCSE obtains a discharge specific capacity of 137.1 mAh·g^(−1)after 150 cycles with a capacity retention rate of 93%at 1 C and 25℃.This study may pave a new avenue for high-performance SPEs.

关键词： solid-state lithium metal battery lamellar composite solid electrolyte β-conformation polyvinylidene fluoride(PVDF) room-temperature ionic conductivity lithium-ion transference number

H∞ Robustness for Distributed Control in Autonomous Microgrids Considering Cyber Disturbances

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 696-706页

作者： Ge Cao Guannan Lou Wei Gu Lina Sheng school of Electrical engineering Southeast UniversityNanjing 210096China

The physical connections and logical relationships between microgrids and communication networks allow microgrids to develop into typical cyber-physical systems(CPSs).With the extensive use of open communication mechanisms,the impact of cyber disturbances in public communication networks cannot be *** this paper,a parameter optimal method for a distributed secondary controller based on the robust control theory and consensus algorithm is presented to enhance the robustness of a secondary control system under data disturbance,parameter perturbation,and time ***,a distributed secondary control strategy of microgrids is demonstrated that coordinates frequency and voltage restoration and power ***,considering the impact of cyber events on the secondary control,a distributed robust controller gain design method is proposed to satisfy the H∞ performance *** solution of the distributed robust control is transformed into a linear matrix in equation problem and latency margin is simultaneously ***,a test microgrid CPS is simulated with and without time delay to investigate the impact of cyber events on system operational states and the effectiveness and robustness of the proposed method.

关键词： Cyber disturbance cyber-physical lsystem distributed control microgrid robust H∞control