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Modeling and optimal energy management of a power split hybrid electric vehicle

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Science China(Technological Sciences) 2017年第5期60卷 713-725页

作者： SHI DeHua wang shaohua Pierluigi Pisu CHEN Long wang RuoChen wang RenGuang School of Automotive and Traffic Engineering Jiangsu University Zhenjiang 212013 China Clemson University International Center for Automotive Research Greenville SC 29607 USA China Automotive Technology and Research Center Tianjin 300300 China

With the combination of engine and two electric machines, the power split device allows higher efficiency of the engine. The operation modes of a power split HEV are analyzed, and the system dynamic model is established for HEV forward simulation and controller design. Considering the fact that the operation modes of the HEV are event-driven and the system dynamics is continuous time-driven for each mode, the structure of the controller is built and described with the hybrid automaton control theory. In this control structure, the mode selection process is depicted by the finite state machine （FSM）. The multi-mode switch controller is designed to realize power distribution. Furthermore, the vehicle mode operations are optimized, and the nonlinear model predictive control （NMPC） strategy is applied by implementing dynamic programming （DP） in the finite pre- diction horizon. Comparative simulation results demonstrate that the hybrid control structure is effective and feasible for HEV energy management design. The NMPC optimal strategy is superior in improving fuel economy.

关键词： hybrid electric vehicle power split energy management model predictive control hybrid system

Ecological Risk Assessment of World Heritage Sites Using RS and GIS:A Case Study of Huangshan Mountain, China

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Chinese Geographical Science 2022年第5期32卷 808-823页

作者： HUANG Shiman HU Qingwu wang shaohua LI Haidong School of Remote Sensing and Information Engineering Wuhan UniversityWuhan 430079China Nanjing Institute of Environ-mental Sciences Ministry of Ecology and EnvironmentNanjing 210042China

Ecological risk assessment(ERA) is an indispensable method for systematic monitoring of World Heritage Sites(WHSs) exposed to various anthropogenic factors and natural disasters. Remote sensing(RS) and geographical information systems(GIS) can eliminate many limitations in traditional ERA methods. In this study, changes in ecological risk at Huangshan Mountain, the first mixed WHS in China, over the period of 1984–2019 were explored using remote sensing images and products by considering both natural disasters and human disturbance. Results show that of the four land cover types in Huangshan Mountain, namely water, forest, building and farmland, the main land cover type is forest. During the 35 yr, lands categorised at low or relatively low ecological risk levels are dominant in Huangshan Mountain, with the lowest and highest ERIs(ecological risk index) in 1990 and 2010, respectively. The areas at the five ecological risk levels have declined as follows: relatively low > low > medium > relatively high > high. Changes in ecological risks are closely related to changes in land cover and natural disasters. Even though major natural disasters may affect the ecological risk level in the whole region, changes in land cover caused by human activities will shift the ecological risk level in some areas. Our attempts can be modified and applied to other sites, and offer policy implications for protection and preservation of WHSs.

关键词： ecological risk assessment ecological risk index(ERI) world heritage site landscape ecological index Huangshan Mountain Remote Sensing

考虑模糊聚类特性的电网运营风险自动预警系统

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电子设计工程 2025年第1期33卷 70-73,79页

作者：孙红燕王少华南方电网数字电网研究院有限公司运营监控中心广东广州510665

当前风险自动预警系统通常采用基于经验值的人工方法设置自动预警阈值,给出的是统一阈值,导致系统虚警率较高。因此,提出基于模糊聚类特性的电网运营风险自动预警系统。设计信息采集器和显示器,应用决策级融合原理和神经网络模型,整合... 详细信息

当前风险自动预警系统通常采用基于经验值的人工方法设置自动预警阈值,给出的是统一阈值,导致系统虚警率较高。因此,提出基于模糊聚类特性的电网运营风险自动预警系统。设计信息采集器和显示器,应用决策级融合原理和神经网络模型,整合实时采集的电网运营多源异构数据。从购电维度、输配电维度和售电维度入手,确定电网运营风险度量指标,得到风险度量结果。依托模糊聚类特性建立动态聚类图,对风险预警对象进行分类,分析电网运营风险的内容,作为自动预警阈值。根据预警阈值定义风险自动预警线,对比风险度量结果生成包含预警等级的自动预警信息。实验结果表明,所提系统的虚警率为2.67%,满足了电网运营风险自动预警要求。

关键词：模糊聚类特性电网运营风险度量自动预警

Quaternary antiferromagnetic Ba2BiFeS5 with isolated FeS4 tetrahedra

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Chinese Physics B 2019年第8期28卷 329-332页

作者： shaohua wang Xiao Zhang Hechang Lei Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials & Micro-nano Devices Renmin University of ChinaBeijing 100872China State Key Laboratory of Information Photonics and Optical Communications & School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

We report the detailed physical properties of quaternary compound Ba2BiFeS5 with the key structural ingredient of isolated FeS4 *** and heat capacity measurements clearly indicate that Ba2BiFeS5 has a paramagnetic to antiferromagnetic transition at about 30 *** calculated magnetic entropy above ordering temperature is much smaller than theoretical value for high-spin Fe^3+ion with S=5/2,implying the possible short-range antiferromagnetic fluctuation in Ba2BiFeS5.

关键词： isolated FeS4 tetrahedra antiferromagnetic transition short-range antiferromagnetic fluctuation

A Hybrid Approach to Modeling and Control of Vehicle Height for Electronically Controlled Air Suspension

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Chinese Journal of Mechanical Engineering 2016年第1期29卷 152-162页

作者： SUN Xiaoqiang CAI Yingfeng wang shaohua LIU Yanling CHEN Long School of Automotive and Traffic Engineering Jiangsu University Automotive Engineering Research Institute Jiangsu University

The control problems associated with vehicle height adjustment of electronically controlled air suspension （ECAS） still pose theoretical challenges for researchers, which manifest themselves in the publications on this subject over the last years. This paper deals with modeling and control of a vehicle height adjustment system for ECAS, which is an example of a hybrid dynamical system due to the coexistence and coupling of continuous variables and discrete events. A mixed logical dynamical （MLD） modeling approach is chosen for capturing enough details of the vehicle height adjustment process. The hybrid dynamic model is constructed on the basis of some assumptions and piecewise linear approximation for components nonlinearities. Then, the on-off statuses of solenoid valves and the piecewise approximation process are described by propositional logic, and the hybrid system is transformed into the set of linear mixed-integer equalities and inequalities, denoted as MLD model, automatically by HYSDEL. Using this model, a hybrid model predictive controller （HMPC） is tuned based on online mixed-integer quadratic optimization （MIQP）. Two different scenarios are considered in the simulation, whose results verify the height adjustment effectiveness of the proposed approach. Explicit solutions of the controller are computed to control the vehicle height adjustment system in realtime using an offline multi-parametric programming technology （MPT）, thus convert the controller into an equivalent explicit piecewise affine form. Finally, bench experiments for vehicle height lifting, holding and lowering procedures are conducted, which demonstrate that the HMPC can adjust the vehicle height by controlling the on-off statuses of solenoid valves directly. This research proposes a new modeling and control method for vehicle height adjustment of ECAS, which leads to a closed-loop system with favorable dynamical properties.

关键词： electronically controlled air suspension vehicle height control hybrid system mixed logical dynamical,model predictive control

Physical Properties of[A6Cl][Fe24Se26](A=K,Rb)with Self-Similar Structure

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Chinese Physics Letters 2020年第1期37卷 74-77页

作者： shaohua wang Qiangwei Yin Hechang Lei Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano Devices Renmin University of ChinaBeijing 100872

We have successfully synthesized two novel compounds[A6Cl][Fe24Se26](A=K,Rb).The key structural units of them are FeSe octamers,consisting of edge-shared FeSe4 *** kinds of FeSe octamer layers with different connection configurations stack along the c axis,forming a three-dimensional(3D)TiAl3-type ***,the 3D structural topology of these ocatmers in one unit cell is similar to the local atomic arrangement of themselves,i.e.,self-similarity in *** property characterizations indicate that both the compounds exhibit insulating antiferromagnetism with Neel temperatures Tn^110K and 75K for[K6Cl][Fe24Se26]and[Rb6Cl][Fe24Se26].

关键词： structure. [Fe Se2

Electrochemical activation of oxygen atom of SnO2 to expedite efficient conversion reaction for alkaline-ion(Li+/Na+/K+)storages

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Nano Research 2023年第1期16卷 1642-1650页

作者： Yong Cheng Bingbing Chen Limin Chang Dongyu Zhang Chunli wang shaohua wang Ping Nie Limin wang Key Laboratory of Preparation and Applications of Environmental Friendly Materials(Jilin Normal University) Ministry of EducationChangchun 130103China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryCASChangchun 130022China Department of Energy Science and Engineering Nanjing Tech UniversityNanjing 210000China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

SnO2-based anode materials have attracted much attention due to high capacity and relatively mild voltage ***,limited by low initial Coulombic efficiency(ICE)and poor stability,its practical application is still ***,it has been found that compositing carbon or metal particles with SnO2 is an effective strategy to achieve high alkaline-ion *** this strategy may improve the kinetics and ICE of the electrochemical reaction,the specific mechanism has not been clearly *** this work,we found that the invalidation SnO2 may go through two steps:1)the conversion process from SnO2 to Sn and Li2O;2)the collapse of the electrode material resulted from huge volume changes during the alloyed Sn with alkaline *** address these issues,a unique robust Co-NC shell derived from ZIF-67 is introduced,in which the transited metallic Co nanoparticles could accelerate the decomposition of Sn-O and Li-O bonds,thus expedite the kinetics of conversion *** a result,the SnO2@Co-NC electrode achieves a more complete and efficient transfer between SnO2 and Sn phases,possessing a potential to achieve high alkaline-ion(Li+/Na+/K+)storages.

关键词： alkaline-ion storage SnO2 anode conversion reaction electron transfer

Progress in research on ice accretions on overhead transmission lines and its influence on mechanical and insulating performance

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Frontiers of Electrical and Electronic Engineering in China 2012年第3期7卷 326-336页

作者： shaohua wang Xingliang JIANG Zhejiang Electric Power Test and Research Institute Hangzhou 310014China College of Electrical Engineering Chongqing University Chongqing400044 China

Atmospheric ice accretion on transmission lines is of great danger to the security of service of electrical power system. This paper reviews the progress in research dealing with the formation of ice accretions on transmission lines and the effects of ice on the mechanical and electrical performance of transmission lines. The results show that ice accretions on transmission lines can be categorized into five types： glaze, hard rime, soft rime, hoar frost, and snow and sleet. In all types of ice accretions, glaze grown in a wet regime is of the greatest danger to the transmission lines. Meteorological conditions, terrain and geographic conditions, and some other factors significantly influence the ice accumulation speed and the ice amount. Drastic decrease of mechanical property and electric property as a result of severe icing is the main reason for ice accidents. The amount of ice, the asymmetrical ice accretion, and the asynchronous ice shedding can considerably change the conductor strain, conductor sag, variation amount of the span, displacement of the insulator string, and the tension difference. The amount and type of ice, the uniformity of ice accumulation, and the con- ductivity of freezing water have significant influence on the flashover voltage of ice-covered insulators.

关键词： transmission lines icing mechanical perfor-mance electrical performance

An interval finite element method based on bilevel Kriging model

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Chinese Journal of Aeronautics 2024年第12期37卷 1-11页

作者： YAO, Zhongyang wang, shaohua WU, Pengge NI, Bingyu JIANG, Chao State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle Engineering Hunan University Changsha 410082 China Flight Automatic Control Research Institute of AVIC Xi'an 710065 China Agriculture Equipment Institute of Hunan Hunan Academy of Agricultural Sciences Changsha 410125 China

This study introduces a new approach utilizing an interval finite element method combined with a bilevel Kriging model to determine the bounds of structural responses in the presence of spatial uncertainties. A notable benefit of this approach is its ability to determine the response bounds across all degrees of freedom with a small sample size, which means that it has high efficiency. Firstly, the spatially varying uncertain parameters are quantified using an interval field model, which is described by a series of standard interval variables within a truncated interval Karhunen-Loève (K-L) series expansion. Secondly, considering that the bound of structural response is a function of spatial position with the property of continuity, a surrogate model for the response bound is constructed, namely the first-level Kriging model. The training samples required for this surrogate model are obtained by establishing the second-level Kriging model. The second-level Kriging model is established to describe the structural responses at particular locations relative to the interval variables so as to facilitate the upper and lower bounds of the node response required by the first-level Kriging model. Finally, the accuracy and effectiveness of the method are verified through examples. © 2024

关键词： Interval field Spatial uncertainty Kriging model Interval finite element analysis Response bounds