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Robust design of static synchronous series compensator-based stabilizer for damping inter-area oscillations using quadratic mathematical programming

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第4期11卷 296-306页

作者： Mahmoud Reza SHAKARAMI Ahad KAZEMI center of excellence for power System automation and operation Department of Electrical EngineeringIran University of Science and Technology

This paper presents a procedure for designing a supplementary damping stabilizer for a static synchronous series compensator(SSSC) in multi-machine power *** objective is to shift the lightly damped inter-area modes toward the prescribed stability region.A lead-lag stabilizer is used to demonstrate this technique,in which a particular measure of stabilizer gain is considered as an objective *** of the problem for phase-lead and lag structures are *** objective function with the constraints is formed as a quadratic mathematical programming *** robust design,the parameters of the stabilizer are calculated under various operating *** types of SSSC-based stabilizer have been presented and *** results including eigenvalue analysis and the nonlinear simulations on the 4-and 50-machine power systems are pre-sented to show the effectiveness of the proposed method.

关键词： Inter-area oscillations Static synchronous series compensator(SSSC) Damping stabilizer Robust design Quadratic mathematical programming

Optimum allocation of FACTS devices in Fars Regional Electric Network using genetic algorithm based goal attainment

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 478-487页

作者： Mohsen GITIZADEH Mohsen KALANTAR center of excellence for power System automation and operation Department of Electrical Engineering Iran University of Science and TechnologyTehran 16844 Iran

This paper presents a novel approach to find optimum locations and capacity of flexible alternating current transmission system (FACTS) devices in a power system using a multi-objective optimization function. Thyristor controlled series compensators (TCSCs) and static var compensators (SVCs) are the utilized FACTS devices. Our objectives are active power loss reduction, newly introduced FACTS devices cost reduction, voltage deviation reduction, and increase on the robustness of the security margin against voltage collapse. The operational and controlling constraints, as well as load constraints, were considered in the optimum allocation. A goal attainment method based on the genetic algorithm (GA) was used to approach the global optimum. The estimated annual load profile was utilized in a sequential quadratic programming (SQP) optimization sub-problem to the optimum siting and sizing of FACTS devices. Fars Regional Electric Network was selected as a practical system to validate the performance and effectiveness of the proposed method. The entire investment of the FACTS devices was paid off and an additional 2.4% savings was made. The cost reduction of peak point power generation implies that power plant expansion can be postponed.

关键词： Flexible alternating current transmission system (FACTS) devices allocation Multi-objective optimization Geneticalgorithm (GA) Goal attainment

Optimal Day-ahead Dynamic Pricing of Grid-connected Residential Renewable Energy Resources Under Different Metering Mechanisms

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Journal of Modern power systems and Clean Energy 2023年第1期11卷 168-178页

作者： Kimia Parandeh Abed Bagheri Shahram Jadid center of excellence for power System automation and operation School of Electrical EngineeringIran University of Science and Technology(IUST)TehranIran

Nowadays,grid-connected renewable energy resources have widespread applications in the electricity ***,providing household consumers with photovoltaic(PV)systems requires bilateral interfaces to exchange energy and *** addition,residential consumers’contribution requires guaranteed privacy and secured data *** dynamic pricing is one of the incentive-based demand response methods that has substantial effects on the integration of renewable energy resources with smart grids and social *** metering mechanisms of renewable energy resources such as feed-in tariffs,net metering,and net purchase and sale are important issues in power grid operation *** this paper,optimal condition decomposition method is used for dayahead dynamic pricing of grid-connected residential renewable energy resources under different metering mechanisms:feed-intariffs,net metering,and net purchase and sale in conjunction with carbon emission *** to the stochastic nature of consumers’load and PV system products,uncertainties are considered in a two-stage decision-making *** results demonstrate that the net metering with the satisfaction average of 68%for consumers and 32%for the investigated electric company leads to 28%total load *** the case of net purchase and sale mechanism,a satisfaction average of 15%for consumers and 85%for the electric company results in 11%total load *** feed-in-tariff mechanism,in spite of increased social welfare,load reduction does not take place.

关键词： Dynamic pricing renewable energy resources feed-in-tariffs net metering net purchase and sale stochastic decision-making

Calculating the transient behavior of grounding systems using inverse Laplace transform

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第3期12卷 250-262页

作者： Nabiollah RAMEZANI Seyed Mohammad SHAHRTASH Behshahr Branch Iran University of Science and TechnologyBehshahr 47137Iran center of excellence for power systems automation and operation Department of Electrical EngineeringIran University of Science and TechnologyTehran 16844Iran

This paper deals with a unified and novel approach for analyzing the frequency and time domain performance of grounding *** proposed procedure is based on solving the full set of Maxwell's equations in the frequency domain,and enables the exact computation of very near fields at the surface of the grounding grid,as well as far fields,by simple and accurate closed-form expressions for solving Sommerfeld *** addition,the soil ionization is easily considered in the proposed *** frequency domain responses are converted to the time domain by fast inverse Laplace *** results are validated and have shown acceptable accuracy.

关键词： Electromagnetic field Near-field computation High frequency performance Soil ionization Grounding system Fast inverse Laplace transform

High-precision magnetic field measurement system based on a coherent population trapping magnetometer onboard the SATech-01 satellite

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Science China Technological Sciences 2025年

作者： Hongbo XUE Wei SONG Haoran ZHAO Yiteng ZHANG Shanzhi YE Jindong WANG Ran TAO Peng SANG Keli CHEN Xingzi BI Bingjun CHENG Bin ZHOU Yongliang XUE Yingying TANG Liu LIU Jinsong LI Xiaocheng ZHU Baoquan LI Jinguo LIU Wen CHEN Xiaofeng ZHANG Yonghe ZHANG Lei LI State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences Key Laboratory of Solar Activity and Space Weather National Space Science Center Chinese Academy of Sciences Key Laboratory of Electronics and Information Technology for Space systems National Space Science Center Chinese Academy of Sciences State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Innovation Academy for Microsatellites Chinese Academy of Sciences

On July 27, 2022, a high-precision system for measuring the magnetic field based on a coherent population trapping magnetometer（referred to as the CPT system） was launched onboard the Space Advanced Technology demonstration satellite（SATech-01） by a ZK-1A rocket. The payload comprises a scalar coherent population trapping magnetometer（CPTM）, triaxial anisotropic magnetoresistance magnetometer（AMRM）, and nano star tracker mounted on a non-magnetic telescopic tubular mast. This configuration enables synchronized measurement of scalar and vector geomagnetic fields, as well as the attitude,making the payload with its compact sensors suitable for applications on miniature satellite platforms. On November 7, 2022,the novel telescopic tubular mast was deployed in orbit, extending to a length of 5.28 m. The CPTM, an absolute scalar magnetometer with an omnidirectional sensor, is the first China-developed quantum/atomic magnetometer successfully operating in space. In orbit, the CPTM has sensitivity of ～10 pT/Hz1/2and can automatically operate under complex magnetic field variations. The difference between the scalar fields obtained using the CPTM and CHAOS model has a mean deviation of–3.73 n T and a standard deviation of 26.11 nT（1σ）, without on-orbit calibration or correction. The miniaturized AMRM has a sensitivity of ～0.3 n T/Hz1/2and maintains stable and reliable operation in orbit. The low-power and miniaturized nano star tracker has a measurement uncertainty of 14.23″（1σ） in orbit. The mission has realized the on-orbit technical verification of the integrated and synchronized detection of the vector magnetic field and attitude and fully validated the system's performance,automation level, and reliability.

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Low-cost sensorless control of four-switch,brushless DC motor drive with direct back-EMF detection

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第2期10卷 201-208页

作者： Abolfazl HALVAEI NIASAR Abolfazl VAHEDI Hassan MOGHBELLI Department of Electrical Engineering Faculty of EngineeringUniversity of Kashan center of excellence for power System automation and operation Iran University of Science and Technology Department of Science and Mathematics Texas A&M University at Qatar

We propose a position sensorless control scheme for a four-switch,three-phase brushless DC motor drive,based on the zero crossing point detection of phase back-EMF voltages using newly defined error functions(EFs). The commutation in-stants are 30° after detected zero crossing points of the EFs. Developed EFs have greater magnitude rather than phase or line voltages so that the sensorless control can work at a lower speed range. Moreover,EFs have smooth transitions around zero voltage level that reduces the commutation errors. EFs are derived from the filtered terminal voltages vao and vbo of two low-pass filters,which are used to eliminate high frequency noises for calculation of the average terminal voltages. The feasibility of the proposed sensorless control is demonstrated by simulation and experimental results.

关键词： Brushless DC motor Four-switch inverter Sensorless control Back-EMF voltage sensing DSP

Interconnection and damping assignment and Euler-Lagrange passivity-based control of photovoltaic/battery hybrid power source for stand-alone applications

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第9期12卷 774-786页

作者： Ali TOFIGHI Mohsen KALANTAR Department of Electrical Engineering Pardis BranchIslamic Azad UniversityPardisIran center of excellence for power System automation and operation Department of Electrical EngineeringIran University of Science and TechnologyTehranIran

A DC hybrid power source composed of photovoltaic cells as the main power source,Li-ion battery storage as the secondary power source,and power electronic interface,is modeled based on port-controlled Hamiltonian systems and Euler-Lagrange ***,passivity-based controllers are *** asymptotic stability is ensured as *** addition,a power management system is designed to manage power flow between *** and simulation of the proposed hybrid power source is accomplished using MATLAB/*** interest is focused on the comparison of the two passivity-based control methods and their use in hybrid power systems.

关键词： DC hybrid power source Euler-Lagrange (EL) equations Interconnection and damping assignment (IDA) Passivity-based control Photovoltaic Li-ion battery

Modeling of D-STATCOM in distribution systems load flow

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第10期8卷 1532-1542页

作者： HOSSEINI Mehdi SHAYANFAR Heidar Ali FOTUHI-FIRUZABAD Mahmud center of excellence for power System automation and operation Department of Electrical Engineering Iran University of Science & Technology Narmak 16846-13114 Tehran Iran Technical Engineering of Babol University of Mazandaran Shariati Ave. 47144 P. O. Box 484 Babol Iran center of excellence for power System automation and operation Department of Electrical Engineering Iran University of Science & Technology Narmak 16846-13114 Tehran Iran Department of Electrical Engineering Sharif University of Technology Azadi Ave. 11365-9363 Tehran Iran

This paper presents modeling of Distribution STATCOM (D-STATCOM) in load flow calculations for the steady- state voltage compensation. An accurate model for D-STATCOM is derived to use in load flow calculations. The rating of this device as well as the direction of required reactive power injection for voltage compensation in the desired value (1 p.u.) is de- rived and discussed analytically and mathematically by the phasor diagram method. Furthermore, an efficient method for node and line identification used in load flow calculations is presented. The validity of the proposed model is examined by using two standard distribution systems consisting of 33 and 69 nodes, respectively. The best location of D-STATCOM for under voltage problem mitigation approach in the distribution networks is determined. The results validate the proposed model for D- STATCOM in large distribution systems.

关键词： Distribution system D-STATCOM Voltage compensation Load flow

Hybrid classifier for fault location in active distribution networks

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Protection and Control of Modern power systems 2020年第1期5卷 194-202页

作者： Sadegh Jamali Alireza Bahmanyar Siavash Ranjbar Centre of excellence for power System automation and operation School of Electrical EngineeringIran University of Science and TechnologyP.O.Box:16846-13114TehranIran

This paper presents a fast hybrid fault location method for active distribution networks with distributed generation(DG)and *** method uses the voltage and current data from the measurement points at the main substation,and the connection points of DG and *** data is used in a single feedforward artificial neural network(ANN)to estimate the distances to fault from all the measuring points.A k-nearest neighbors(KNN)classifier then interprets the ANN outputs and estimates a single fault *** results validate the accuracy of the fault location method under different fault conditions including fault types,fault points,and fault *** performance is also validated for non-synchronized measurements and measurement errors.

关键词： Artificial neural networks Distributed generation Distribution networks Fault location K-nearest neighbors