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CSEE Journal of Power and Energy Systems 2023年第5期9卷 1881-1892页

作者： Chen Lyu Wanxing Sheng Keyan Liu xinzhou dong Department of Electrical Engineering Tsinghua UniversityBeijing 100084China the China Electric Power Research Institute Beijing 100192China

A large number of load power and power output of distributed generation in an active distribution network(ADN)are uncertain,which causes the classical affine power flow method to encounter problems of interval expansion and low efficiency when applied to an *** then leads to errors of interval power flow data sources in the cyber physical system(CPS)of an *** order to improve the accuracy of interval power flow data in the CPS of an ADN,an affine power flow method of an ADN for restraining interval expansion is *** at the expansion of interval results caused by the approximation error of non-affine operations in an affine power flow method,the approximation method of the new noise source coefficient is improved,and it is proved that the improved method is superior to the classical method in restraining interval *** overcome the decrease of computational efficiency caused by new noise sources,a novel merging method of new noise sources in an iterative process is *** tests are conducted on an IEEE 33-bus,PG&E 69-bus and an actual 1180-bus system,which proves the validity of the proposed affine power flow method and its advantages in terms of computational efficiency and restraining interval expansion.

关键词： Active distribution network affine power flow interval expansion new noise source uncertainty

Islanding detection based on asymmetric tripping of feeder circuit breaker in ungrounded power distribution system

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Journal of Modern Power Systems and Clean Energy 2015年第4期3卷 526-532页

作者： Yuwei SHANG Shenxing SHI xinzhou dong State Key Laboratory of Power Systems Department of Electrical EngineeringTsinghua UniversityBeijing 100084China

An islanding detection method in ungrounded power distribution system based on single-phase operating mechanisms of the circuit breaker(CB)is proposed in this *** CB opens three phase circuits to form an island,one phase circuit is opened firstly and the other two phase circuits are opened secondly after certain *** the period when only one phase circuit is opened,negative sequence voltage with certain duration is obtained at DG side because of the asymmetric operation of the *** all three phase circuits are opened,the voltage variation direction of the two phases that are secondly disconnected from the grid follows the voltage variation direction of the firstly disconnected *** on the above voltage characteristics,an islanding detection scheme is proposed to identify genuine islanding from system *** performance of the proposed scheme is tested in PSCAD/EMTDC using a 10 kV distribution network with synchronous DG *** results demonstrate the proposed method is effective and reliable to detect islanding formation.

关键词： Distributed generation Islanding detection Circuit breaker Single-phase operating mechanisms

Novel directional comparison protection for distribution lines

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Science China(Technological Sciences) 2008年第4期51卷 353-361页

作者： dong xinzhou YUAN DingDing LU Qiang BO ZhiQian State Key Lab.of Power System Department of Electrical EngineeringTsinghua UniversityBeijing 100084China EAI AREVA Transimission&Distribution Ltd.StaffordUK 不详

For quickly clearing up a fault of distribution lines, which concerned with complex structure and operating modes, a directional comparison protection is necessary. The paper evaluated the traditional directional relay through modeling a typical distribution system and presented a novel negative sequence directional relay and a new directional comparison protection scheme specially designed for distribution systems. In the relay and the protection scheme, a particular negative sequence component has been constructed to solve the problem that there is no negative sequence component in a symmetrical fault case so that they could operate correctly in both asymmetrical fault and symmetrical fault. Extensive EMTP simulation studies proved that the protection schemes are able to provide fast and reliable responses for all fault conditions. In particular, they are able to give correct responses adapting to the change of system operation conditions, including the changing of system configuration, power flow direction, and source and tapped-offload conditions.

关键词： distribution lines negative sequence directional relay directional comparison protection

Optimizing solution of fault location using single terminal quantities

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Science China(Technological Sciences) 2008年第6期51卷 761-772页

作者： dong xinzhou SHI ShenXing CUI Tao LU Qiang State key lab.Of power system Department of Electrical EngineeringTsinghua UniversityBeijing 100084China

This paper firstly evaluated the impedance method and traveling waves method for fault location, and studied the robustness of fault location method based on im-pedance. Then it proposed an assembled fault location method for a transmission line based on single-terminal electrical quantities, in which the fault zone was firstly determined by impedance method with robustness then the accurate fault position was pinpointed by traveling waves method. EMTP (Electromagnetic Transient Pro-gram) simulations showed that the proposed method can overcome the drawbacks of impedance method and traveling waves method when either one is used alone, and improve both the accuracy and the reliability of fault location.

关键词： transmission line accurate fault location traveling waves method impedance method assembled method

Arc flash fault detection in wind farm collection feeders based on current waveform analysis

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Journal of Modern Power Systems and Clean Energy 2017年第2期5卷 211-219页

作者： Bin WANG Jiang NI Jianzhao GENG Yuanyuan LU xinzhou dong State Key Laboratory of Power System Department of Electrical EngineeringTsinghua UniversityBeijing 100084China

High impedance faults(HIFs) are easy to occur in collective feeders in wind farms and may cause the cascading of wind generators tripping. This kind of faults is difficult to be detected by traditional relay or fuse due to the limited fault current values and the situation is worse in wind farms. The mostly adopted HIF detection algorithms are based on the 3rd harmonic characteristic of the fault zero-sequence currents, whereas these 3rd harmonics are very easy to be polluted by wind power back-to-back converters. In response to this problem, the typical harmonic characteristic of HIF arc flash based on Mayr’s arc model is first analyzed, and the typical fault waveforms of HIF in wind farm are presented. Then the performance of the harmonic based HIF detection algorithm is discussed,and a novel detection algorithm is proposed from the viewpoint of time domain, focusing on the convex and concave characteristic of zero-sequence current at zerocrossing points. A HIFs detection(HIFD) prototype implementing the proposed algorithm has been *** sensitivity and security of the algorithm are proved byfield data and RTDS experiments.

关键词： Wind farm High impedance fault Arc flash Zero-sequence current Convex and concave characteristic

Characteristics of Controlled Bridge Circuit and Its Application in Magnetic Field Induction Measurement

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Tsinghua Science and Technology 2024年第4期29卷 1105-1117页

作者： Yanchu Li Qingqing Ding Mingchen Yan Jiyao Wang Jun Xu xinzhou dong Department of Electrical Engineering Tsinghua UniversityBeijing 100084China State Key Laboratory of Control and Simulation of Power System and Generation Equipments Tsinghua UniversityBeijing 100084China School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 100096China

The article designs a new type of bridge circuit with a controlled source—when the resistance on the bridge arm of the controlled source bridge circuit meets the bridge balance condition, and the bridge branch contains only one Current-Controlled Current Source (CCCS), a Voltage-Controlled Current Source (VCCS), a Current-Controlled Voltage Source (CCVS), or a Voltage-Controlled Voltage Source (VCVS), the circuit is called a controlled bridge circuit, which has the characteristics of bridge balance. Due to the relationship between the controlled source and the bridge arm, the sensitivity of the components on the bridge is higher mathematically and logically. When applied to measurement, engineering, automatic control, and other fields, the controlled bridge circuit has higher control ac-curacy. Mathematical derivation and simulation results prove the correctness of the bridge balance conclusion and the special properties of this bridge when applied to the measurement field.

关键词： bridge bircuit bridge circuit applications bridge balanced condition controlled bridge circuit magnetic field induction measurement

Smart Power Substation Development in China

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CSEE Journal of Power and Energy Systems 2016年第4期2卷 1-5页

作者： xinzhou dong Delin Wang Manyong Zhao Bin Wang Shenxing Shi Alexander Apostolov Tsinghua University Beijing 100084China National Electric Power Dispatch and Control Center Beijing 100031China Dispatcher Centre China Southern Power Grid CompanyGuangzhou 510663China Protection Automation&Control WorldLos AngelesCAUSA

Over the past decade,China has undertaken substation intellectualization of more than 2000 substation operations in three *** experience has been achieved during this developmental *** this paper,the status of smart substation development in China is systematically presented,as well as future directions of the smart substation,such as adoption of the hierarchical protection and control system.

关键词： Backup protection optimization data sharing IEC61850 protection and control integration smart power substation wide area protection

Analysis on the fault characteristics of three-phase short-circuit for half-wavelength AC transmission lines

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Global Energy Interconnection 2018年第2期1卷 115-121页

作者： Xuankun Song Teng Feng Liu Han Travis MSmith xinzhou dong Wenxuan Liu Rui Zhang State Grid Economic and Technological Research Institute CO. LTD. Oak Ridge National Laboratory Tsinghua University

Half-wavelength AC transmission(HWACT) is an ultra-long distance AC transmission technology, whose electrical distance is close to half-wavelength at the system power frequency. It is very important for the construction and operation of HWACT to analyze its fault features and corresponding protection technology. In this paper, the steady-state voltage and current characteristics of the bus bar and fault point and the steady-state overvoltage distribution along the line will be analyzed when a three-phase symmetrical short-circuit fault occurs on an HWACT line. On this basis, the threephase fault characteristics for longer transmission lines are also studied.

关键词： Half-wavelength AC transmission Fault characteristics Three-phase short-circuit Fault distance Overvoltage

Research on Multi-Scale Modeling of Grid-Connected Distributed Photovoltaic Power Generation

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Energy and Power Engineering 2017年第4期9卷 127-140页

作者： Chen Lv Wanxing Sheng Keyan Liu xinzhou dong China Electric Power Research Institute Haidian District Beijing China Department of Electrical Engineering Tsinghua University Beijing China

The complexity of distribution network model mainly depends on the model scale of grid-connected distributed photovoltaic (PV) power generation. Therefore, the simulation performance of multi-scale PV model is the key factor of the simulation accuracy in the specific operating scenarios of distribution network. In this paper, a multi-scale model of grid connected PV distributed generation system is proposed based on the mathematical model of grid-connected distributed PV power generation. It is analyzed that differences of simulation performance, such as adaptability of simulation step size, accuracy of output and the effect on voltage profile of distribution network, between PV models with different scales in IEEE 33 node example. Simulation results indicate that the multi-scale model is effective in improving the accuracy and efficiency of simulation under different operating conditions of distribution network.

关键词： PV Distributed Generation Multi-Scale Modeling Simulation Step Size Output Power Voltage Profile

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具有抗过渡电阻能力的多相补偿距离继电器

中国电机工程学报 2014年第19期34卷 3220-3225页

作者：崔柳董新洲电力系统及发电设备控制和仿真国家重点实验室(清华大学电机系) 北京市海淀区100084

多相补偿距离继电器不受系统振荡影响,但抗过渡电阻能力差,为此,提出一种具有抗过渡电阻能力的多相补偿距离继电器。通过对多相补偿距离继电器动作方程的分析,找到了过渡电阻在该动作方程中的作用项。整定点的零序电压具有同该作用项极... 详细信息

多相补偿距离继电器不受系统振荡影响,但抗过渡电阻能力差,为此,提出一种具有抗过渡电阻能力的多相补偿距离继电器。通过对多相补偿距离继电器动作方程的分析,找到了过渡电阻在该动作方程中的作用项。整定点的零序电压具有同该作用项极相似的形式。通过在动作方程中引入整定点的零序电压,同时用保护整定点的电压代替故障点故障前电压,可提取该作用项。进而利用线路阻抗角和该项的实虚部,可减小或消除过渡电阻对多相补偿距离继电器的影响。基于以上原理,提出一种具有抗过度电阻能力的多相补偿距离继电器。理论分析和仿真计算证明了所提继电器具有良好的抗过渡电阻能力。

关键词：距离保护过渡电阻多相补偿距离继电器单相接地故障误差分析