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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 597-607页

作者： Dawei Liao Fei Gao Daniel J.Rogers Wentao Huang Dong Liu houjun tang Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghaiChina Department of Engineering Science University of OxfordOxford OX12JDU.K. IEEE

This paper introduces a distributed secondary control scheme for achieving current sharing and average voltage regulation objectives in a DC *** proposed scheme employs a dynamic diffusion algorithm(DDA)instead of the consensus algorithm to enable distributed communication among *** help understand DDA,the relation of DDA and other diffusion algorithms is discussed in detail and its superiority is shown by comparison with diffusion and consensus ***,considering the discrete nature and different sampling time of the digital controller and communication network,a z-domain model of the entire DC microgrid is *** influence of communication and secondary control parameters on the system stability is *** on the established model,the tolerable communication rates are ***-time simulations conducted on the OPAL-RT platform validate the effectiveness of the proposed scheme,showcasing its advantages in terms of convergence speed and stability.

关键词： Cooperative control DC microgrid diffusion algorithm discrete-time modeling distributed secondary control

Direct adaptive control for nonlinear uncertain system based on control Lyapunov function method

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Journal of Systems Engineering and Electronics 2006年第3期17卷 619-623页

作者： Chen Yimei Han Zhengzhi tang houjun Dept. of Automation Tianjin Polytechnic Univ. Tianjin 300160 P. R. China School of Electronic Information & Electrical Engineering Shanghai Jiaotong Univ. Shanghai 200030 P. R. China

The problem of adaptive stabilization of a class of multi-input nonlinear systems with unknown parameters both in the state vector-field and the input vector-field has been considered. By employing the control Lyapunov function method, a direct adaptive controller is designed to complete the global adaptive stability of the uncertain system. At the same time, the controller is also verified to possess the optimality. Example and simulations are provided to illustrate the effectiveness of the proposed method.

关键词： adaptive control control Lyapunov function nonlinear uncertain system optimality.

TYRE DYNAMICS MODELLING OF VEHICLE BASED ON SUPPORT VECTOR MACHINES

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Chinese Journal of Mechanical Engineering 2006年第4期19卷 558-565页

作者： ZHENG Shuibo tang houjun HAN Zhengzhi ZHANG Yong School of Electronic Information and Electrical Engineering Shanghai Jiaotong University Shanghai 200030 China Institute of Automotive Engineering Shanghai Jiaotong University Shanghai 200030 China

Various methods of tyre modelling are implemented from pure theoretical to empirical or semi-empirical models based on experimental results. A new way of representing tyre data obtained from measurements is presented via support vector machines （SVMs）. The feasibility of applying SVMs to steady-state tyre modelling is investigated by comparison with three-layer backpropagation （BP） neural network at pure slip and combined slip. The results indicate SVMs outperform the BP neural network in modelling the tyre characteristics with better generalization performance. The SVMsqyre is implemented in 8-DOF vehicle model for vehicle dynamics simulation by means of the PAC 2002 Magic Formula as reference. The SVMs-tyre can be a competitive and accurate method to model a tyre for vehicle dynamics simuLation.

关键词： Support vector machines(SVMs) Backpropagation(BP) neural network Tyre model Regression estimation Magic formula

Solving large-scale multiclass learning problems via an efficient support vector classifier

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Journal of Systems Engineering and Electronics 2006年第4期17卷 910-915页

作者： Zheng Shuibo tang houjun Han Zhengzhi Zhang Haoran School of Electrical and Information Engineering Shanghai Jiaotong Univ. Shanghai 200030 R R. China Dept. of Electronic Engineering Zhejiang Normal Univ. Jinhua 321004 P. R. China

Support vector machines （SVMs） are initially designed for binary classification. How to effectively extend them for multiclass classification is still an ongoing research topic. A multiclass classifier is constructed by combining SVM^light algorithm with directed acyclic graph SVM （DAGSVM） method, named DAGSVM^light A new method is proposed to select the working set which is identical to the working set selected by SVM^light approach. Experimental results indicate DAGSVM^light is competitive with DAGSMO. It is more suitable for practice use. It may be an especially useful tool for large-scale multiclass classification problems and lead to more widespread use of SVMs in the engineering community due to its good performance.

关键词： support vector machines (SVMs) multiclass classification decomposition method SVM^light sequential minimal optimization (SMO).

Response Time of Reactive Power Based on Different Definitions and Algorithms

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Journal of Modern Power Systems and Clean Energy 2021年第2期9卷 440-449页

作者： Taixun Fang Qiwen Zhou Fengfeng Ding Xiaodan Wu Zhao Li houjun tang NR Electric Co. Ltd.NanjingChina the Key Laboratory of Control of Power Transmission and Transformation Ministry of EducationShanghai Jiao Tong UniversityShanghaiChina

Dynamic reactive power compensation equipment typically requires a fast response to output the necessary reactive *** term"dynamic response time of reactive power"is often used but has never been clearly *** paper summarizes the reactive power calculations under different definitions and algorithms and considers these calculations in terms of signal processing to simulate and analyze the step *** paper subsequently focuses on the widely used instantaneous reactive power algorithm and finally concludes that the dynamic reactive power response time closely depends on the reactive power calculation method *** single-phase instantaneous reactive power algorithm has the fastest response *** reactive power response time of dynamic reactive devices in power systems is a minimum of a quarter of one cycle time for the well-known and widely used single-phase reactive power algorithms.

关键词： Response time reactive power instantaneous reactive power Hilbert transform phase shift synchronous reference frame

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致密油田注水吞吐采出程度影响因素实验研究

当代化工 2024年第4期53卷 897-900页

作者：杨宏拓唐后军李留杰郭粉转孙建陕西延长石油(集团)有限责任公司研究院陕西西安710065 西安石油大学陕西西安710065

为探索致密油藏注水吞吐提高采收率影响因素,以鄂尔多斯盆地长8致密油储层为研究对象,开展了长岩心室内吞吐实验,研究了渗透率、闷井时间、注入水量、注水速度、吞吐周期、注入压力对长8致密油储层采出程度的影响因素。结果表明:对于致... 详细信息

为探索致密油藏注水吞吐提高采收率影响因素,以鄂尔多斯盆地长8致密油储层为研究对象,开展了长岩心室内吞吐实验,研究了渗透率、闷井时间、注入水量、注水速度、吞吐周期、注入压力对长8致密油储层采出程度的影响因素。结果表明:对于致密油长8储层,基质渗透率影响注水吞吐效果,渗透率越大,注水吞吐采出程度越高;原油与基质中的流体交换效率受油焖井时间影响,焖井时间越长,流体交换越充分,最终采出程度越高,但焖井时间存在临界值;注水量、注水速度是地层能量的有效补充,影响吞吐的最终采出程度,注水速度越低,越容易发挥毛细管力的渗吸作用,吞吐效果越好,注水量存在临界值,超过临界值后容易形成优势通道,影响采出效果;注入压力影响岩心内部渗吸作用发生的范围,从而影响最终采出程度,注入压力越高,注入水进入的孔隙越多,渗吸发生的范围越大,吞吐效果越好。研究成果对致密油高效补充能量开发提供借鉴。

关键词：鄂尔多斯盆地致密油储层注水吞吐长岩心驱替

Contemporary Trends in Power Electronics Converters for Charging Solutions of Electric Vehicles

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CSEE Journal of Power and Energy Systems 2020年第4期6卷 911-929页

作者： Salman Habib Muhammad Mansoor Khan Farukh Abbas Abdar Ali Muhammad Talib Faiz Farheen Ehsan houjun tang School of Electronic Information and Electrical Engineeringand Key Laboratory of Control of Power Transmission and ConversionShanghai Jiao Tong UniversityShanghai 200240China Department of Electrical Engineering University of Engineering and TechnologyLahore 54890Pakistan School of International and Public Affairs Shanghai Jiao Tong UniversityShanghai 200240China

Electrifying the transport sector requires new possibilities for power electronics converters to attain reliable and efficient charging solutions for electric vehicles(EVs).With the continuous development in power electronics converters,the desire to reduce gasoline consumption and to increase the battery capacity for more electric range is achievable for EVs in the near *** main interface between the power network and EV battery system is a power electronics converter,therefore,there is a considerable need of new power converters with low cost and high reliability for the advance charging mechanism of *** rapid growth in power converter topologies brings substantial opportunities in EV charging *** view of this fact,this paper investigates the significant aspects,current progress,and challenges associated with several power converters to suggest further improvements in charging systems of *** particular,an extensive analysis of front-end as well as back-end converter configurations is ***,the comparative properties of resonant converter topologies along with other DCDC converters are discussed in ***,isolated,and non-isolated topologies with soft switching techniques are classified and rigorously analyzed with a view to their respective issues and *** is foreseen that this paper would be a valuable addition and a worthy source of information for researchers exploring the area of power converter topologies for charging solutions of EVs.

关键词： Batteries chargers converter topologies electric vehicles(EVs) power electronics plug-in hybrid electric vehicles(PHEVs)

ExaHDF5: Delivering Efficient Parallel I/O on Exascale Computing Systems

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Journal of Computer Science & Technology 2020年第1期35卷 145-160页

作者： Suren Byna M.Scot Breitenfeld Bin Dong Quincey Koziol Elena Pourmal Dana Robinson Jerome Soumagne houjun tang Venkatram Vishwanath Richard Warren Lawrence Berkeley National Laboratory BerkeleyCA 94597U.S.A The HDF Group ChampaignIL 61820U.S.A Argonne National Laboratory LemontIL 60439U.S.A

Scientific applications at exascale generate and analyze massive amounts of data.A critical requirement of these applications is the capability to access and manage this data efficiently on exascale *** I/O,the key technology enables moving data between compute nodes and storage,faces monumental challenges from new applications,memory,and storage architectures considered in the designs of exascale *** the storage hierarchy is expanding to include node-local persistent memory,burst buffers,etc.,as well as disk-based storage,data movement among these layers must be *** I/O libraries of the future should be capable of handling file sizes of many terabytes and *** this paper,we describe new capabilities we have developed in Hierarchical Data Format version 5(HDF5),the most popular parallel I/O library for scientific ***5 is one of the most used libraries at the leadership computing facilities for performing parallel I/O on existing HPC *** state-of-the-art features we describe include:Virtual Object Layer(VOL),Data Elevator,asynchronous I/O,full-featured single-writer and multiple-reader(Full SWMR),and parallel *** this paper,we introduce these features,their implementations,and the performance and feature benefits to applications and other libraries.

关键词： parallel I/O Hierarchical Data Format version 5(HDF5) I/O performance virtual object layer HDF5 optimizations

A framework for stochastic estimation of electric vehicle charging behavior for risk assessment of distribution networks

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Frontiers in Energy 2020年第2期14卷 298-317页

作者： Salman HABIB Muhammad Mansoor KHAN Farukh ABBAS Muhammad NUMAN Yaqoob ALI houjun tang Xuhui YAN Key Laboratory of Control of Power Transmission and Transformation of the Ministry of Education School of ElectronicInformation and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Electrical Engineering University of Engineering and TechnologyLahore 54890Pakistan State Grid Liyang Power Supply Company Liyang 213300China

Power systems are being transformed to enhance the *** paper contributes to the knowledge regarding the operational process of future power networks by developing a realistic and stochastic charging model of electric vehicles(EVs).Large-scale integration of EVs into residential distribution networks(RDNs)is an evolving issue of paramount significance for utility *** voltages prevent effective and reliable operation of *** EV loads require a stochastic approach to predict EVs charging demand,consequently,a probabilistic model is developed to account several realistic aspects comprising charging time,battery capacity,driving mileage,state-of-charge,traveling frequency,charging power,and time-of-use mechanism under peak and off-peak charging *** attempt is made to examine risks associated with RDNs by applying a stochastic model of EVs charging *** output of EV stochastic model obtained from Monte-Carlo simulations is utilized to evaluate the power quality parameters of *** equipment capability of RDNs must be evaluated to determine the potential *** specifications of RDNs including voltage unbalance factor,voltage behavior,domestic transformer limits and feeder losses are assessed in context to EV charging scenarios with various charging power levels at different penetration ***,the impact assessment of EVs on RDNs is found to majorly rely on the type and location of a power network.

关键词： electric vehicles(EVs) residential distribution networks(RDNs) voltage unbalance factor(VUF) state-of charge(SOC) time-of-use(TOU)

一种适用于延长油田长7页岩油水平井产量预测的改进经验模型

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非常规油气 2024年第4期11卷 106-114页

作者：李留杰唐后军郭粉转杨宏拓罗麟梁卫卫肖胜东凃兴平张天龙陕西延长石油(集团)有限责任公司研究院西安710065

延长油田长7陆相页岩油水平井产量前期快速递减、后期缓慢递减。在采用常见的页岩油气经验模型YM-SEPD和Duong法拟合月产和累产数据的基础上,通过定义“截距累产”,引入新的中间变量,在线性拟合中间变量时将拟合月产改为拟合累产,提出... 详细信息

延长油田长7陆相页岩油水平井产量前期快速递减、后期缓慢递减。在采用常见的页岩油气经验模型YM-SEPD和Duong法拟合月产和累产数据的基础上,通过定义“截距累产”,引入新的中间变量,在线性拟合中间变量时将拟合月产改为拟合累产,提出了一种新的改进Duong模型,并与另外一种改进Duong模型(WK-Duong模型)进行了对比。结果表明:1)YM-SEPD和Duong模型受月产数据波动影响较大,其中YM-SEPD累产拟合误差的正负值随时间的增加而改变,而Duong模型拟合误差逐渐增大;2)采用WK-Duong模型拟合关键参数q_(1)时,认为拟合直线截距为0,与延长油田陆相页岩油实际生产情况不符,影响拟合精度;3)新的改进Duong法通过拟合累产与相关参数关系,减小了月产数据波动对线性拟合的影响,优化了后续求解过程,与其他几种方法相比拟合精度最高。改进后的Duong方法可用于准确拟合和预测延长油田长7页岩油水平井产量,对陆相页岩油的产量评价具有参考意义。

关键词：延长油田长7 陆相页岩油产量预测经验模型改进Duong模型