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IEEE Conference on Energy Internet and Energy System Integration (EI2)

作者： Yi Xu Jianhua Li Xiangjun Zeng Kun Yu Xiaotao Che Fang Liu Hunan Province Key Laboratory of Smart Grids Operation and Control Changsha University of Science & Technology Changsha China State Grid Luoyang Power Supply Company Luoyang China

ISBN: (数字)9781728131375

ISBN: (纸本)9781728131382

The premise of reliable arc extinguishing performance by current transfer arc extinguishing technology is to accurately identify the fault phase. This paper analyzes the neutral point voltage and the relative ground voltage variation law when single-line-to-ground (SLG) fault occurs, and obtains a SLG fault phase selection method. Then, an improved scheme for the fault-phase misjudgment and anti-phase short circuit of the current transfer arc-extinguishing device is proposed to improve its reliability. Finally, the action flow of the current transfer arc extinguishing device is described. The feasibility of the principle of current transfer arc suppression technology and the rationality of the action flow are verified by simulation analysis. The results show that the current transfer arc extinguishing technology can theoretically achieve the purpose of quickly eliminating the arc grounding fault, and help to improve the power supply reliability of the power distribution system.

关键词： Circuit faults Grounding Switches Power supplies Capacitance Monitoring Accidents

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Vertically integrated outdoor in-site line protection based on SoC technique

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全球能源互联网（英文版） 2019年第2期1卷 179-186页

作者： Tonghua Wu Yuping Zheng Yutao Qiu Xiaoping Zhang Gang Yao Jimin Chai Xiaofan Hou College of Energy and Electrical Engineering Hehai University Nanjing 210098 China NARI Group Corporation/State Grid Electric Power Research Institute Nanjing 211106 China State Key Laboratory of Smart Grid Protection and Control Nanjing 211106 China State Grid Zhejiang Electric Power Corporation Hangzhou 310007 China Electrical and System Engineering University of Birmingham Birmingham B152TT UK NARI Group Corporation/State Grid Electric Power Research Institute Nanjing 211106 China State Key Laboratory of Smart Grid Protection and Control Nanjing 211106 China College of Energy and Electrical Engineering Hehai University Nanjing 210098 China

By focusing on the problems of speed, reliability, operation and maintenance in the practical application of line protection in conventional and smart substations, we propose system architecture and a technical scheme for in-site (similar in meaning to on-site or near-process) line protection based on vertical integration and outdoor installation. The functions of the single-bay merging unit, relay protection, and intelligent terminal are vertically integrated to reduce the number and types of devices, simplify the configuration, reduce signal transmission, and shorten the protection action time. In addition, this vertically integrated device is applied to provide data acquisition and control execution support for substation-area protection, security and stability of devices, and other substation-area devices. The vital performance outputs are tested and compared. Finally, the experimental results verify that the proposed scheme is feasible and the technology is advanced.

关键词： Line protection In-site relay protection Merging unit Vertical integration

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Passgrid: Towards graph-supplemented textual shoulder surfing resistant authentication 1

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5th International Symposium on Security and Privacy in Social Networks and Big Data, SocialSec 2019

作者： Zhou, Teng Liu, Liang Wang, Haifeng Li, Wenjuan Jiang, Chong College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing China NARI Technology Co. Ltd. State Key Laboratory of Smart Grid Protection and Control in China Nanjing China Department of Computer Science City University of Hong Kong Hong Kong School of Computer Science Guangzhou University Guangzhou China

ISBN: (数字)9789811507588

ISBN: (纸本)9789811507571

With the rapid development of intelligent mobile devices and network applications, user authentication plays an important role to help protect people’s privacy and sensitive information. A large number of authentication textual and graphical schemes have been proposed in the literature, but the majority of them are vulnerable to shoulder surfing attacks, or have to sacrifice usability. Motivated by this challenge, we propose a graph-supplemented textual shoulder surfing resistant authentication system, called Passgrid. With a series of one-time login indicators and cyclic movable blocks with textual elements, Passgrid prevents attackers from guessing the passwords even with the help of a camera. To reduce users’ workload, they only have to memorize one set of the password. Our user study shows that Passgrid can achieve good performance regarding security and usability, i.e., average login time consumption of 22s with a small password length. © Springer Nature Singapore Pte Ltd. 2019.

关键词： Authentication

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Adaptive algorithm for rapidly optimising the generator-tripping control

Adaptive algorithm for rapidly optimising the generator-trip...

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作者： Huang, Tiangang Xue, Yusheng Xue, Feng Zhao, Junhua Zhang, Jianmin NARI Group Corporation State Grid Electric Power Research Institute Nanjing211106 China School of Electrical Engineering Southeast University Nanjing210096 China State Key Laboratory of Smart Grid Protection and Control Nanjing211106 China School of Science and Engineering Chinese University of Hong Kong Shenzhen518100 China College of Automation Hangzhou Dianzi University Hangzhou310018 China

The fast optimisation of transient stability emergency control (TSEC) strategy is a key factor of online safeguard for AC-DC interconnected systems. An engineering applicable TSEC algorithm has to obtain the disturbed trajectories of the system by numerical integration, and then do quantised stability knowledge mining. Theoretical analysis and simulation verification reveal that the premise is to identify the unstable mode correctly, and then emergency control decision can be optimised according to the cost performance of the actions. Small integral step is usually needed for accuracy. In order to coordinate the accuracy and computational burden intelligently, this study proposes an algorithm for optimising generator-tripping control, which can adaptively reduce computational burden. If the unstable mode is insensitive to the change of fault parameters (e.g. fault clearing time), this case's time-varying property is more likely to be weak. Only for such cases, large-step Taylor series expansions (LSTSE) can be taken to replace small-step numerical integration (SSNI) and search for the optimal result. Based on its time-varying property, each case can get disturbed trajectories using LSTSE or SSNI adaptively and obtain optimal solution. The excellent performance of this algorithm is verified by simulation of nine Chinese regional power systems under various operating conditions. © 2019 Institution of Engineering and *** right reserved.

关键词： Adaptive algorithms

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Vertically integrated outdoor in-site line protection based on SoC technique

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Global Energy Interconnection 2018年第2期1卷 179-186页

作者： Tonghua Wu Yuping Zheng Yutao Qiu Xiaoping Zhang Gang Yao Jimin Chai Xiaofan Hou College of Energy and Electrical Engineering Hehai University NARI Group Corporation/State Grid Electric Power Research Institute State Key Laboratory of Smart Grid Protection and Control State Grid Zhejiang Electric Power Corporation Electrical and System Engineering University of Birmingham

By focusing on the problems of speed, reliability, operation and maintenance in the practical application of line protection in conventional and smart substations, we propose system architecture and a technical scheme for in-site(similar in meaning to on-site or near-process) line protection based on vertical integration and outdoor installation. The functions of the single-bay merging unit, relay protection, and intelligent terminal are vertically integrated to reduce the number and types of devices, simplify the configuration, reduce signal transmission, and shorten the protection action time. In addition, this vertically integrated device is applied to provide data acquisition and control execution support for substation-area protection, security and stability of devices, and other substation-area devices. The vital performance outputs are tested and compared. Finally, the experimental results verify that the proposed scheme is feasible and the technology is advanced.

关键词： Line protection In-site relay protection Merging unit Vertical integration

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LCC-HVDC supplementary controller design based on global fast terminal sliding mode control 2

LCC-HVDC supplementary controller design based on global fas...

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2nd IEEE International Conference on Energy Internet, ICEI 2018

作者： Liu, Qipu Sun, Guoqiang Nong, Weizhi Lin, Zijie Tang, Xiaochen Yang, Jia College of Energy and Electrical Engineering Hohai University Nanjing China State Key Laboratory of Smart Grid Protection and Control NARI Group Corporation Nanjing China

ISBN: (纸本)9781538641316

Conventional LCC-HVDC is a non-linear, tightly coupled system. Since the performance of PI control varies from different operation conditions, the optimal of parameter tuning is only achieved under steady state. To improve dynamic performance and stability of system, A novel HVDC nonlinear supplementary controller based on Terminal sliding mode theorem has been proposed. First, the steady state mathematical model of the LCC-HVDC system is built, the approach of state feedback exact linearization is adopted to change the nonlinear model into a linear one, the decoupled relationship between the control variables are investigated;then based on sliding mode control method, the constant current and constant voltage control in rectifier and inverter has been achieved, respectively. The variables converge to equilibrium point fast and exactly. Finally, the strategy is demonstrated through Matlab/Simulink software, the simulation results show that the controller is capable of tracing the reference, and the robustness with respect to parameters' perturbations is satisfied. The controller contributes significantly toward improving transient performance comparing to conventional PI control and restraining commutation failure. © 2018 IEEE.

关键词： controllers

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Reliability analysis of security and stability control system with typical structure in power grids

Reliability analysis of security and stability control syste...

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IEEE General Meeting Power& Energy Society

作者： Xijian Dong Chanan Singh Heping Jia Bijun Li State Key Laboratory of Smart Grid Protection and Control NARI Group Corporation Nanjing China Texas A&M University College Station USA State Grid Economic and Technological Research Institute Co. LTD. Beijing China

The security and stability control system (SSCS) is the second line of defense for prevention of security breach and control of power systems in China. With the development of smart grid technologies, it has been becoming more complex with an increasing trend of reliability requirements. In this paper, a typical application of SSCS in the power grid and its optimized design for ensuring its correct action are introduced. The Markov process model is developed to evaluate the availability of the proposed SSCS. The concept and algorithm of integrity for the SSCS are proposed with the consideration of equipment availability and functional reliability. Combined with the conclusion of the integrity calculation, useful suggestions for the design of SSCS are provided.

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混合多端直流输电系统保护方法研究

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Engineering 2021年第8期7卷 65-88页

作者：郑玉平何佳伟李斌吴通华戴魏李晔 State Key Laboratory of Smart Grid Protection and Control State Grid Electric Power Research Institute (NARI Group Corporation) College of Energy and Electrical Engineering Hohai University Key Laboratory of Smart Grid of Ministry of Education Tianjin University

近年来，混合多端直流输电系统快速发展。但是，在混合直流系统中应用的电压源换流器（voltage-source converter, VSC）出口不再需要直流滤波器。此外，考虑到其直流故障电流可被换流器自身有效抑制，直流线路两端也不再需要安装限流... 详细信息

近年来，混合多端直流输电系统快速发展。但是，在混合直流系统中应用的电压源换流器（voltage-source converter, VSC）出口不再需要直流滤波器。此外，考虑到其直流故障电流可被换流器自身有效抑制，直流线路两端也不再需要安装限流电抗器。这意味着线路两端边界缺失，导致应用于常规高压直流输电（line commutated converter based high-voltage direct current, LCC-HVDC）系统和柔性直流（VSC-HVDC）电网的单端量保护均无法适用于混合多端直流输电系统。为此，本文提出了一种适用于混合多端直流输电系统的单端量保护新原理，该方法主要基于暂态信息和主动注入思想实现故障辨识。与应用于LCCHVDC和VSC-HVDC系统的单端量保护相比，所提方法无需依赖线路两端的边界元件，因此更加适用于混合多端直流系统。大量的仿真算例充分验证了所提方法的可行性和优越性。

关键词：混合多端直流输电系统单端量保护暂态量信息主动注入

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Research on low/high voltage ride through of PV gridconnected system based on control-hardware-in-the-loop

Research on low/high voltage ride through of PV gridconnecte...

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2019 Tsinghua International Doctoral Forum

作者： Shuang Li Gangquan Si Kai Qu Guoqing He State Key Laboratory of Electrical Insulation and Power Equipment Shaanxi Key Laboratory of Smart Grid School of Electrical Engineering Xi'an Jiaotong University Xi'an Shaanxi Province China State Key Laboratory of Operation and Control of Renewable Energy & Storage Systems China Electric Power Research Institute Haidian District Beijing China

ISBN: (纸本)9781839533907

Fault ride-through capability is one of the important grid-connection indexes for large-scale generation of PV power and other renewable energy, which is of great significance for the safe and stable operation of the grid. In order to improve the fault ride-through capability of PV grid-connected inverter, a comprehensive control strategy of LVRT/HVRT of PV gridconnected inverter based on conventional control scheme is proposed in this paper. Meanwhile, the LVRT/HVRT test platform of PV grid-connected inverter was built by using the simulation technology of RT-LAB hardware-in-the-loop. Firstly, based on the eHS (electric hardware solver) technology of RT-LAB real-time simulation software, a set of PV grid-connected inverter semi-physical simulation system was built, mainly including PV simulator, PV inverter, filter circuit, three-phase controlled voltage source, etc. Then, according to the technical specification of PV grid-connected inverter, the fault ridethrough control strategy of PV grid-connected inverter under the condition of voltage drop/rise symmetrically is proposed. Finally, the simulation tests of LVRT/HVRT were carried out on the simulation platform with the controller of PV inverter. Simulation results show that the proposed control strategy meets the grid-connected requirements during LVRT/HVRT. In addition, it has good dynamic and static characteristics.

关键词： PV grid-connected inverter control-hardware-in-the-loop LVRT HVRT Polydnaviridae Inventors ride-through control strategy

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A method of automatic generation of daily work report for power dispatching based on RoBERTa

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IOP Conference Series: Materials Science and Engineering 2020年第1期853卷

作者： Jie Li Tao Zhang Hao Li Jixiang Lu Jinjun Lu Ziqi Li State Grid Jiangsu Electric Power Co. LTD Technology Research Center of NARI Group Corporation Nanjing China State Key Laboratory of Intelligent Power Grid Protection and Operation Control Nanjing China

Power dispatching operators need to read a large number of power dispatching logs every day and arrange them into daily work reports. It takes them a lot of time to do information extraction and transfer that information into work reports. In order to reduce the workload of power dispatching operators, we propose an intelligent method for automatic generation of daily work reports in this paper by adopting RoBERTa, which is an improved version of BERT. With the outstanding performance of RoBERTa in semantic analysis and entity recognition, the workload of power dispatching operators is reduced approximately 50% through our proposed method, which means the efficiency is greatly improved.

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