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Online inertia Estimation Using Electromechanical Oscillation Modal Extracted from Synchronized Ambient Data

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Journal of Modern Power Systems and Clean Energy 2022年第1期10卷 241-244页

作者： Bo Wang Deyou Yang Guowei Cai Jin Ma Zhe Chen Lixin Wang School of Electrical Engineering Northeast Electrical Power UniversityJilin 132012China School of Electrical and Information Engineering The University of SydneySydneyAustralia Department of Energy Technology Aalborg UniversityAalborgDenmark

An ambient modal framework for inertia estimation using synchrophasor data is proposed in this letter.Specifically,an analytical formulation is developed for the estimation of inertia based on the frequency and damping ratio modes extracted from ambient data.An advantage of the proposed framework is that it can rely on synchronized ambient data under non-disturbed conditions for online estimation and tracking of inertia.Ultimately,numerical simulation studies and physical experiments demonstrate the feasibility of the proposed approach.

关键词： inertia electromechanical oscillation ambient modal

inertia EFFECTS OF THE FLUID AND CYLINDER IN COAXIAL CYLINDRICAL RHEOMETER

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Acta Mechanica Sinica 1998年第3期14卷 234-238页

作者：张建保匡震邦 Dept.of Physics The Forth Military Medical UniversityXi'an 710032China Dept.of Eng.Mechanics Shanghai Jiaotong UniversityShanghai 200240China

The inertias of the fluid and the inner cylinder in coaxial cylinder rheometer (CACR) have great influence on the unsteady flow of non-Newtonian fluid. Even for the Newtonian fluid there exist the so called stress overshoot phenomenon. This phenomenon was studied and a method correcting the measured results for an unsteady flow in the rheometer was proposed. It is found that the inertia effect of the fluid can be ignored when the gap between cylinders is small. (Edited author abstract) 11 Refs.

关键词： inertia rheometer fluid hemorheology

Dynamic inertia Response Support by Energy Storage System with Renewable Energy Integration Substation

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Journal of Modern Power Systems and Clean Energy 2020年第2期8卷 260-266页

作者： Yeuntae Yoo Seungmin Jung Gilsoo Jang Korea University SeoulKorea Hanbat National University DaejeonKorea

In recent years,the expansion of renewable energy in electric power systems has been increasing at such a rapid pace that it has started affecting frequency stability.Renewable generators connected to the grid produce variable amounts of power,and in most cases have no inherent inertia response(IR)to the system frequency.Therefore,the high penetration of renewable generators in the system results in low inertia and frequency distortion.If renewable generators account for a high proportion of the supply in a power system,the use of energy storage systems(ESSs)with frequency-support algorithms(in the place of synchronous generators)can stabilize the network.The participation of ESSs in frequency support must be organized precisely,so that they are fully devoted to their own purpose.In this paper,the frequency-support parameters of ESSs are calculated for achieving stable frequency response from a network.An estimation and calibration process is conducted during the active power-order change of the ESSs in the substation,and is verified through electromagnetic-transients-including-DC(EMTDC)-based simulations.

关键词： Energy storage system(ESS) frequency response inertia renewable energy substation

Difference in moments of inertia and paring interaction strength in superdeformed nuclei

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Science China Mathematics 1997年第6期40卷 652-657页

作者：雷奕安林纯镇曾谨言 Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China Department of Physics Peking University Beijing 100871 China Department of Physics Peking University Beijing 100871 China Also at Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China.

The difference in the bandhead moments of inertia between the superdeformed (SD) band 194Hg(1) and the two-quasiparticle SD bands 194Hg(2,3) was investigated using the particle-number-conserving treatment for the cranked shell model Hamiltonian, and the pairing interaction strength in SD nuclei is estimated to be much weaker than that in normally deformed nuclei.

关键词： super-deformed band difference in moments of inertia particle-number-conserving treatment pairing interaction strength.

Effect of inertia nonlinearity on dynamic response of an asymmetric building equipped with tuned mass dampers

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Earthquake Engineering and Engineering Vibration 2020年第2期19卷 499-513页

作者： Hassan Rezazadeh Fereidoun Amini Majid Amin Afshar School of Civil Engineering Iran University of Science and TechnologyP.O.Box 16765-163TehranIran Department of Technology and Engineering Imam Khomeini International University NorouzianP.O.Box 34149-16818QazvinIran

This study investigates the effect of nonlinear inertia on the dynamic response of an asymmetric building equipped with Tuned Mass Dampers(TMDs).In the field of structural engineering,many researchers have developed models to study the behavior of nonlinear TMDs,but the effect of nonlinear inertia has not received as much attention for asymmetric buildings.To consider nonlinear inertia,the equations of motion are derived in a local rotary coordinates system.The displacements and rotations of the modeled building and TMDs are defined by five-degree-of-freedom(5-DOFs).The equations of motion are derived by using the Lagrangian method.Also in the proposed nonlinear model,the equations of motion are different from a conventional linear model.In order to compare the response of the proposed nonlinear model and a conventional linear model,numerical examples are presented and the response of the modeled buildings are derived under harmonic and earthquake excitations.It is shown that if the nonlinear inertia is considered,the response of the modeled structures changes and the conventional linear approach cannot adequately model the dynamic behavior of the asymmetric buildings which are equipped with TMDs.

关键词： Nonlinear inertia tuned mass damper asymmetric buildings harmonic excitation seismic excitation

A new measuring technique of soil thermal inertia

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Science China(Technological Sciences) 2000年第S1期43卷 62-69页

作者：孙晓敏朱治林唐新斋苏红波张仁华 Institute of Geography Chinese Academy of Sciences Beijing China

Thermal inertia is the function of substance density, heat capacity and heat diffusivity, and is an important parameter for researching the process of surface heat balance using remote sensing technique. In this paper, using soil heat plates, infrared thermometer, data logger and other instruments, by man-controlled changing the solar radiation status on the soil samples, the authors gave a new method to measure soil thermal inertia. Using the continuously surveying data of soil heat flux and infrared radiation temperature, thermal inertia can be calculated easily. Based on the thermal inertia calculation of three soil samples with different water content, good results were abtained by the authors, so this method is feasible. Meanwhile, this measuring technique is also a new attempt.

关键词： soil thermal inertia quick measurement new method.

Systematic odd-even differences in the moments of inertia of superdeformed bands and blocking effect

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Science China Mathematics 1995年第6期38卷 730-738页

作者：曾谨言雷奕安赵恩广 Department of Physics Peking University Beijing 100871 China Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China

A comprehensive analysis of the superdeformed bands observed near A≈190 indicates that there exist systematic odd-even differences in the moments of inertia similar to that observed in normally deformed nuclei, which can be considered as compelling evidence for pairing and blocking effect in super-deformed nudei. With increasing rotational frequency the odd-even differences become weaker and weaker due to the Coriolis anti-pairing effects. Particularly, the odd-even differences in the dynamic moments of inertia become obscure when hω≥2 MeV, and in certain cases there emerges nearly identical value of J(2) for some neighboring nudei. However, the odd-even differences in the kinematic moments of inertia still remain to certain extent at the highest frequencies.

关键词： superdeformed nuclei odd-even difference in moments of inertia blocking effect.

Measurement of Moment of inertia Based on Hilbert Transform

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Transactions of Tianjin University 2013年第3期19卷 225-230页

作者：赵岩张晓琳王军唐文彦 School of Electrical Engineering and Automation Harbin Institute of Technology

A measurement model based on torsion pendulum was established,in which nonlinear damping and nonlinear restoring force were considered.The calculation method of the moment of inertia was based on Hilbert transform.The motion of torsion pendulum showed the time-frequency characteristics due to the nonlinear factors,which were validated by the experimental data.The analytical signal was formed by Hilbert transform of the angular displacement signal of the test object.The moment of inertia can be computed by the instantaneous undamped natural frequency with Hilbert transform.Prior to the implementation of Hilbert transform,the empirical mode decomposition was used to filter the experimental signal.The moment of inertia of the test object was measured by the torsion pendulum system.The experimental results show that the relative measurement error of the moment of inertia was within 0.7%,which indicated the validity of the measurement method.

关键词： moment of inertia Hilbert transform empirical mode decomposition nonlinear system

Review of System Strength and inertia Requirements for the National Electricity Market of Australia

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CSEE Journal of Power and Energy Systems 2019年第3期5卷 295-305页

作者： Huajie Gu Ruifeng Yan Tapan Saha Power and Energy Systems Research Group School of Information Technology and Electrical EngineeringThe University of QueenslandBrisbane St LuciaQLD 4072Australia

Synchronous generators(SGs)are still making major contributions to the re-stabilization of a power system following voltage/frequency disturbances,attributed to their inherent capability of providing system strength and inertia.However,SGs powered by fossil fuels are operating to a lesser extent and scheduled for decommissioning in the National Electricity Market(NEM)of Australia due to the accelerating increase of low bidding priced asynchronous generation of wind and solar,which leads to the reduction and even in some cases,a shortage of system strength and inertia.This paper comprehensively reviews the requirements of system strength and inertia in the NEM from an operational security perspective.Australia is the first country that established the regulation rules of system strength and inertia to accommodate issues of an emerging high penetration level of non-synchronous renewable generation.

关键词： inertia power system renewable energy system strength