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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1614-1624页

作者： Yanling Lin Xiaohu Zhang Jianhui Wang Di Shi Desong Bian GEIRI North America San JoseUSA Southern Methodist University DallasUSA

This paper proposes a voltage stability constrained optimal power flow(VSC-OPF)for an unbalanced distribution system with distributed generators(DGs)based on semidefinite programming(SDP).The AC optimal power flow(ACOPF)for unbalanced distribution systems is formulated as a chordal relaxation-based SDP *** minimal singular value(MSV)of the power flow Jacobian matrix is adopted to indicate the voltage stability *** Jacobian matrix can be explicitly expressed by ACOPF state *** nonlinear constraint on the Jacobian MSV is then replaced with its maximal convex subset using linear matrix inequality(LMI),which can be incorporated in the SDP-based ACOPF formulation.A penalty technique is leveraged to improve the exactness of the SDP *** studies performed on several IEEE test systems validate the effectiveness of the proposed method.

关键词： voltage stability semidefinite programming Jacobian matrix optimal power flow

Reconstruction Residuals Based Long-term voltage stability Assessment Using Autoencoders

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Journal of Modern Power Systems and Clean Energy 2020年第6期8卷 1092-1103页

作者： Haosen Yang Robert C.Qiu Houjie Tong the Department of Electrical Engineering Center for Big Data and Artificial IntelligenceShanghai Jiaotong UniversityShanghai 200240China School of Electronic Information and Communication Huazhong University of Science and TechnologyWuhan 430000China IEEE

Real-time voltage stability assessment(VSA)has long been an extensively research *** recent years,rapidly mounting deep learning methods have pushed online VSA to a new height that large amounts of learning algorithms are applied for VSA from the perspective of measurement *** learning methods generally require a large dataset which contains measurements in both secure and insecure states,or even unstable ***,in practice,the data of insecure or unstable state is very rare,as the power system should be guaranteed to operate far away from voltage *** this circumstance,this paper proposes an autoencoder based method which merely needs data of secure state to evaluate voltage stability of a power *** principle of this method is that an autoencoder purely trained by secure data is expected to only create precise reconstruction for secure data,while it fails to rebuild data of insecure ***,the residual of reconstruction is effective in indicating ***,to develop a more accurate and robust algorithm,long short-term memory(LSTM)networks combined with fully-connected(FC)layers are used to build the autoencoder,and a moving strategy is introduced to bias the features of testing data toward the secure feature *** experiments and comparison with traditional machine learning algorithms demonstrate the effectiveness and high accuracy of the proposed method.

关键词： Reconstruction loss autoencoders voltage stability long-short-term memory(LSTM) feature moving strategy

Defect engineering of rutile TiO_(2) ceramics:Route to high voltage stability of colossal permittivity

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Journal of Materials Science & Technology 2021年第25期84卷 10-15页

作者： Yang Yu Yu Zhao Yu-Long Qiao Yu Feng Wei-Li Li Wei-Dong Fei School of Electrical and Electronic Engineering Harbin University of Science and TechnologyHarbin 150080China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Research Center of Basic Space Science Harbin Institute of TechnologyHarbin 150001China National Key Laboratory of Science and Technology on Precision Heat Processing of Metals Harbin Institute of TechnologyHarbin 150001China

Donor-acceptor co-doped rutile TiO_(2) ceramics with colossal permittivity(CP)have been extensively investigated in recent years due to their potential applications in modern *** addition to CP and low dielectric loss,voltage stability is an essential property for CP materials utilized in high-power and high-energy density storage ***,the voltage stability of CP materials based on codoped TiO_(2) does not catch enough ***,we propose a strategy to enhance the voltage stability of co-doped TiO_(2),where different ionic defect clusters are formed by two acceptor ions with different radii to localize free carriers and result in high performance CP ***(Ta+Al+La)co-doped TiO_(2) ceramic with suitable La/Al ratio exhibits colossal permittivity with excellent temperature stability as well as outstanding dc bias *** density functional theory analysis suggests that La^(3+)Al^(3+)V_(0)Ti^(3+)defect clusters and Ta^(5+)-Al^(3+)pairs are responsible for the excellent dielectric properties in(Ta+Al+La)co-doped TiO_(2).The results and mechanisms presented in this work open up a feasible route to design high performance CP materials via defect engineering.

关键词： Colossal permittivity Co-doped TiO_(2) Defect cluster voltage stability

An Adaptive Many-objective Robust Optimization Model of Dynamic Reactive Power Sources for voltage stability Enhancement

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Journal of Modern Power Systems and Clean Energy 2023年第6期11卷 1756-1769页

作者： Yuan Chi Anqi Tao Xiaolong Xu Qianggang Wang Niancheng Zhou IEEE State Key Laboratory of Power Transmission Equipment and System Security and New Technology Chongqing UniversityChongqing 400044China

The deployment of dynamic reactive power sourcecan effectively improve the voltage performance after a disturbance for a power system with increasing wind power penetration level and ubiquitous induction *** improve the voltage stability of the power system,this paper proposes an adaptive many-objective robust optimization model to deal with thedeployment issue of dynamic reactive power ***,two metrics are adopted to assess the voltage stability of the system at two different stages,and one metric is proposed to assess the tie-line reactive power ***,a robustness index isdeveloped to assess the sensitivity of a solution when subjectedto operational uncertainties,using the estimation of acceptablesensitivity region(ASR)and D-vine *** objectives areoptimized simultaneously:①total equipment investment;②adaptive short-term voltage stability evaluation;③tie-line power flow evaluation;④prioritized steady-state voltage stabilityevaluation;and⑤robustness ***,an anglebased adaptive many-objective evolutionary algorithm(MaOEA)is developed with two improvements designed for the application in a practical engineering problem:①adaptive mutationrate;and②elimination procedure without a requirement for athreshold *** proposed model is verified on a modifiedNordic 74-bus system and a real-world power *** results demonstrate the effectiveness and efficiency of theproposed model.

关键词： voltage stability reactive power planning robust many-objective optimization tie-line correlated uncertainty

A New Proximity Indicator for Assessment of voltage stability and Critical Loadability Point

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Energy Engineering 2022年第3期119卷 947-963页

作者： Chandrakant Dondariya D.K.Sakravdia Department of Electrical Engineering Ujjain Engineering CollegeUjjainIndia

This paper presents a newly developed proximity indicator for voltage stability assessment which can be used to predict critical real system load and voltages at various load buses at critical loading *** proximity indicator varies almost parabolic with total real load demand and reaches orthogonally to real load *** relation has been utilized to predict critical loading *** has been shown that two operating points are needed for estimating critical point and proper selection of operating points and variation of proximity indicator near collapse point highly affect the accuracy of *** is based on load flow equations and system real and reactive loadings have been increased in proportion with base case scenario for IEEE 14 and IEEE 25 bus test systems to demonstrate the behaviour of proposed proximity *** has been used as benchmark to check the accuracy of estimation.

关键词： voltage stability voltage collapse proximity indicator critical loading CPF

A novel method to investigate voltage stability of IEEE-14 bus wind integrated system using PSAT

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Frontiers in Energy 2020年第2期14卷 410-418页

作者： Satish KUMAR Ashwani KUMAR N.K.SHARMA Department of Electrical Engineering National Institute of Technology(NIT)KurukshetraHaryana 136119India Department of Electrical Engineering G L Bajaj Institute of Technology and ManagementGreater NoidaUtter Pradesh 201306India

The maximum demand of power utilization is increasing exponentially from base load to peak load in day to day *** power demand may be either industrial usage or household *** meet this high maximum power demand by the consumer,one of the options is the integration of renewable energy resources with conventional power generation *** the present scenario,wind energy system is one of the methods to generate power in connection with the conventional power *** the load on the conventional grid system increases,various bus voltages of the system tend to decrease,causing serious voltage drop or voltage instability within the *** view of this,identification of weak buses within the system has become *** paper presents the line indices method to identify these weak buses,so that some corrective action may be taken to compensate for this drop in *** attempt has been made to compensate these drops in voltages by integration of renewable energy *** wind energy system at one of the bus in the test system is integrated and the performance of the system is verified by calculating the power flow(PF)using the power system analysis tool box(PSAT)and line indices of the integrated test *** PF and load flow results are used to calculate line indices for the IEEE-14 bus test system which is simulated on PSAT.

关键词： voltage stability line indices power system analysis tool box(PSAT) wind system line loading power flow(PF)

voltage stability analysis based on short circuit capacity

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Voltage stability analysis based on short circuit capacity

Investigation of Connecting Wind Turbine to Radial Distribution System on voltage stability Using SI Index and λ - V Curves

第30届中国控制与决策会议

作者： Cheng Xueting Wang Tan Liu Xinyuan Pi Jun Meng Tao Wang Zhipeng State Grid Shanxi Electric Power Research Institute State Grid Shanxi Electric Power Company

voltage stability has been seriously affected in many countries, and the problem of voltage stability has become increasingly prominent with the gradual expansion of interconnection scale and the rapid growth of power demand. Aiming at the problem of voltage stability, taking the Shanxi power grid as an example, the paper demonstrates the short-circuit capacity and voltage stability of the bus.

关键词： voltage stability short circuit capacity

来源： cnki会议评论

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Smart Grid and Renewable Energy 2016年第1期7卷 16-45页

作者： Gamal Abd El-Azeem Mahmoud Eyad Saeed Solimanx Oda Department of Electrical Engineering Faculty of Engineering Suez Canal University Ismailia Egypt

The growth of wind energy penetration level in distribution system raises the concern about its impact on the operation of the power system, especially voltage stability and power loss. Among the major concerns, this paper studied the impact of connecting wind Turbine (WT) in radial distribution system with different penetration levels and different power factor (lead and lag) on power system voltage stability and power loss reduction. Load flow calculation was carried out using forward-backward sweep method. The analysis proceeds on 9- and 33-bus radial distribution systems. Results show that voltage stability enhancement and power loss reduction should be considered as WT installation objective.

关键词： Power Loss Radial Distribution System Si Index voltage stability Optimal Size and Location of Wind Turbine

Improving voltage stability of Power System by Optimal Location of FACTS Devices Using Bio-Inspired Algorithms

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Circuits and Systems 2016年第6期7卷 805-813页

作者： Archana Naganathan Vidhyapriya Ranganathan Department of Information Technology PSG College of Technology Coimbatore India

Power system operations can be optimized using power electronics based FACTS devices. The location of these devices at appropriate transmission line plays a major role in their performance. In this paper, two bio-inspired algorithms are used to optimally locate two FACTS devices: UPFC and STATCOM, so as to reduce the voltage collapse and real power losses. Particle swarm optimization and BAT algorithms are chosen as their behaviour is similar. VCPI index is used as a metric to calculate the voltage collapse scenario of the power system. The algorithm is tested on two benchmark power systems: IEEE 118 and the Indian UPSEB 75 bus system. Performance metrics are compared with the system without FACTS devices. Application of PSO and BAT algorithms to optimally locate the FACTS devices reduces the VCPI index and real power losses in the system.

关键词： BAT FACTS Optimal Location PSO STATCOM UPFC voltage stability

Analysis of grid-connected voltage stability of FSCWT based on bifurcation theory

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Journal of Measurement Science and Instrumentation 2018年第1期9卷 16-24页

作者： HE Ai-huan ZHANG Rui-ping DONG Hai-ying School of Automation and Electrical Engineering Lanzhou Jiaotong UniversityLanzhou 730070China School of Energy and Power Engineering Lanzhou Jiaotong UniversityWuwei 733000China

This paper studies on the change mechanisms of the voltage stability caused by the grid connection of front-end speed-controlled wind turbines(FSCWT)integrating into power *** of all,the differential algebraic equations describing the dynamic characteristics of wind turbines are ***,under the guidance of IEEE3 node system model,the influence of the angular velocity of wind turbines,the reactive power and the active power at load bus on the voltage stability of grid-connection has been analyzed by using bifurcation ***,the method of linear-state feedback control has been applied to the original system in accordance with the bifurcation phenomenon of grid-connected voltage caused by the increase in the active power at load *** shows that voltage at the grid-connected point would be changed with the fluctuation of turbines angular *** increasing its reactive power can enhance voltage at the grid-connected point;problem of bifurcation at the grid-connected point can be delayed when increasing the gain k s of feedback controller within a certain range.

关键词： bifurcation theory power system front-end speed controlled wind turbines(FSCWT) voltage stability