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CSEE Journal of Power and Energy Systems 2025年第1期11卷 115-123页

作者： Ye Guo Yifei Xu Hongbin Sun boming zhang Tsinghua-Berkeley Shenzhen Institute(TBSI) Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China Department of Electrical Engineering State Key Laboratory of Power SystemsTsinghua UniversityBeijing100084China

To achieve more precise monitoring of state fluctuations in the power network close to renewable energy sources, it is necessary to utilize phasor measurements and shorten the time interval between state estimations. For large-scale power systems, however, estimating all of their states with shorter time intervals means a drastic increase in computational burden. As a tradeoff between accuracy and computational efficiency, a multi-time interval forecasting-aided state estimation approach is proposed in this paper, where states with various degrees of fluctuations are estimated asynchronously with different time intervals. Based on the newest state estimate, forecasting-aided state estimators are employed to predict states at time moments prior to the next round of measurement update and state estimation. Extensive numerical tests have demonstrated the effectiveness of the proposed approach.

关键词： Forecasting-aided state estimation phasor measurement renewable energy sources state estimation time interval

Damping and Mechanical Properties of Cocured Composite Laminates with Embedded Perforate Viscoelastic Layer

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Journal of Materials Science & Technology 2009年第4期25卷 543-546页

作者： Lijian Pan boming zhang TCentre for Composite Materials and Structure Harbin Institute of Technology Harbin 150080 China

The composite laminates with embedded acrylonitrile butadiene rubber （NBR） layer were fabricated by cocuring process. The embedded layers were perforated with a series of small holes to allow resin to flow through the damping layer and completely couple the structure to improve bending stiffness and interlaminar shearing strength of these cocured composite laminates. The damping, bending stiffness and shearing strength of these composite laminates with different perforation diameters were investigated. The experimental results show that increasing the perforation diameter leads to significant decreases in damping and significant increase in bending stiffness up to an area ratio of 7.065%. The area ratio here is defined as the ratio of perforation area to the total damping area. Beyond the area ratio of 7.065%, increasing the diameter to an area ratio of 50.24% results in only a slight variation in damping and bending stiffness. Moreover, increasing the perforation diameter does not always increase the shearing strength of the embedded viscoelastic layer. The shearing strength of embedded viscoelastic layer increases only when the area ratio is greater than 19.625%; instead, it will decrease.

关键词： Composite laminates Perforate viscoelastic layer Cocured Damping Mechanical Properties

Multi-objective Optimization of Co-cured Composite Laminates with Embedded Viscoelastic Damping Layer

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Journal of Materials Science & Technology 2009年第5期25卷 708-712页

作者： Lijian Pan boming zhang Fuhong Dai Centre for Composite Materials and Structure Harbin Institute of Technology Harbin 150080 China

Presented herein is a methodology for the multi-objective optimization of damping and bending stiffness of cocoured composite laminates with embedded viscoelastic damping layer. The embedded viscoelastic damping layer is perforated with a series of small holes, and the ratio of the perforation area to the total damping area is the design variable of the methodology. The multi-objective optimization is converted into a single-objective problem by an evaluation function which is a liner weigh sum of the two sub-objective functions. The proposed methodology was carried out to determine the optimal perforation area ratios of two viscoelstic layers with different perforation distance embedded in two composite plates. Both the optimal perforation area ratios are approximate to 2.2%. However, the objective value of the plate with greater perforation distance in embedded viscoelatic layer is much greater.

关键词： Composite laminates Viscoelastic damping layer Co-cured Multi-objective optimization

Prediction on Carbon/Carbon Composites Ablative Performance by Artificial Neutral Net

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Journal of Materials Science & Technology 2008年第6期24卷 945-952页

作者： Guanghui BAI Songhe MENG boming zhang Yang LIU Harbin Institute of Technology Harbin 150001 China

A preliminary estimation of ablation property for carbon-carbon composites by artificial neutral net （ANN） method was presented. It was found that the carbon-carbon composites＇ density, degree of graphitization and the sort of matrix are the key controlling factors for its ablative performance. Then, a brief fuzzy mathematical relationship was established between these factors and ablative performance. Through experiments, the performance of the ANN was evaluated, which was used in the ablative performance prediction of C/C composites. When the training set, the structure and the training parameter of the net change, the best match ratio of these parameters was achieved. Based on the match ratio, this paper forecasts and evaluates the carbon-carbon ablation performance. Through experiences, the ablative performance prediction of carbon-carbon using ANN can achieve the line ablation rate, which satisfies the need of precision of practical engineering fields.

关键词： Carbon-carbon material Ablation property predict Control factor Artificial neutral net

Prediction of the Biaxial Failure Strength of Composite Laminates with Unit Cell Analytic Model

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Journal of Wuhan University of Technology(Materials Science) 2014年第5期29卷 923-927页

作者：赵琳 zhang boming QING Xinlin School of Aerospace Tsinghua University Beijing Aeronautical Science & Technology Research Institute of COMAC School of Materials Science and Engineering Beihang University

A new method to predict the ultimate strength of fiber reinforced composites under arbitrary load condition is introduced. The micromechanics strength theory is used to perform the final failure prediction of composite laminates. The theory is based on unit cell analytic model which can provide the ply composite material properties by only using the constituent fiber and matrix properties and the laminate geometric parameters without knowing any experimental information of the laminates. To show that this method is suitable for predicting the strength of composite laminates, the micromechanics strength theory is ranked by comparing it with all the micro-level and the best two macro-level theories chosen from the World Wide Failure Exercise. The results show that this method can be used for predicting strength of any composite laminates and provide a direct reference for composite optimum design.

关键词： composites strength failure criteria unit cell analytic model

High Temperature Thermal Physical Properties of High-alumina Fibrous Insulation

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Journal of Materials Science & Technology 2007年第6期23卷 860-864页

作者： boming zhang Shuyuan ZHAO Xiaodong HE Shanyi DU Center for Composite Materials and Structure Harbin Institute of Technology Harbin 150080 China

The thermal properties of high-alumina fibrous insulation which filled in metallic thermal protection system were investigated. The effective thermal conductivities of the fibrous insulation were measured under an atmospheric pressure from 10^-2 to 10^5 Pa. In addition, the changes of the specific heat and Rosseland mean extinction coefficient were experimentally determined under various surrounding temperatures up to 973 K. The spectral extinction coefficients were obtained from transmittance data in the wavelength range of 2.5- 25 μm using Beer＇s law. Rosseland mean extinction coefficients as a function of temperature were calculated based on spectral extinction coefficients at various temperatures. The results show that thermal conductivities of the sample increase with increasing temperature and pressure. Specific heat increases as temperature increases, which shows that the capacity of heat absorption increases gradually with temperature. Rosseland mean extinction coefficients of the sample decrease firstly and then increase with increasing the temperature.

关键词： Effective thermal conductivity Extinction coefficient Transmittance Thermalphysical properties

Stress transfer around a broken fiber in unidirectional fiber-reinforced composites considering matrix damage evolution and interface slipping

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Science China(Physics,Mechanics & Astronomy) 2011年第2期54卷 296-302页

作者： YANG Zhong zhang boming ZHAO Lin SUN XinYang Center for Composite Materials. Harbin Institute of Technology. Harbin 150001. China School of Materials Science and Engineering. Beihang University. Beijing 100191. China

A shear-lag model is applied to study the stress transfer around a broken fiber within unidirectional fiber-reinforced composites(FRC) subjected to uniaxial tensile loading along the fiber *** matrix damage and interfacial debonding,which are the main failure modes,are considered in the *** maximum stress criterion with the linear damage evolution theory is used for the *** slipping friction stress is considered in the interfacial debonding region using Coulomb friction theory,in which interfacial clamping stress comes from radial residual stress and mismatch of Poisson's ratios of constituents(fiber and matrix).The stress distributions in the fiber and matrix are obtained by the shear-lag theory added with boundary conditions,which includes force continuity and displacement compatibility constraints in the broken and neighboring intact *** result gives axial stress distribution in fibers and shear stress in the interface and compares the theory reasonably well with the measurement by a polarized light *** relation curves between damage,debonding and ineffective region lengths with external strain loading are obtained.

关键词： stress transfer shear-lag damage evolution fiber composite

Transient outage model considering corrective and preventive maintenance

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Journal of Modern Power Systems and Clean Energy 2016年第4期4卷 680-689页

作者： Guoqiang JI Wenchuan WU boming zhang Hongbin SUN Tsinghua University BeijingChina

Traditional outage model for the power equipment usually focus on the behavior of the equipment under random factors,and the availability of the power equipment in system analysis is usually confined to the steady ***,this model may be inaccurate in the short term analysis,where the transient process of availability has not ended ***,the power equipment in the short term analysis might be influenced by both random factors and deterministic factors,yet the impact of deterministic factors cannot be completely reflected in the traditional outage *** on the above issues,a Markov-based transient outage model is proposed in this paper,which describes the deterioration and repair process of an *** the corrective maintenance and preventive maintenance are concerned in the *** preventive maintenance in the model is considered as deterministic event,in which the start time and duration are both *** the corrective maintenance and the unexpected failure are modeled as random *** transient state probability and availability of equipment under preventive maintenance is *** effect of deterministic events on the availability of equipment is analyzed on numerical *** proposed model can be used in the short-term reliability assessment and maintenance scheduling in actual systems.

关键词： Outage model Preventive maintenance Corrective maintenance Markov process Transient availability

A two-level hierarchical discrete-device control method for power networks with integrated wind farms

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Journal of Modern Power Systems and Clean Energy 2019年第1期7卷 88-98页

作者： Fengda XU Qinglai GUO Hongbin SUN boming zhang Lin JIA Department of Electrical Engineering Tsinghua University North China Branch State Grid Corporation of China

Power systems depend on discrete devices, such as shunt capacitors/reactors and on-load tap changers, for their long-term *** transmission systems that contain large wind farms, we must take into account the uncertainties in wind power generation when deciding when to operate these *** this paper, we describe a method to schedule the operation of these devices over the course of the following *** schedules are designed to minimize wind-power generation curtailment, bus voltage violations, and dynamic reactive-power deviations,even under the worst possible *** voltagecontrol decisions are initiated every 15 min using a dynamic optimization algorithm that predicts the state of the system over the next 4-hour *** this, forecasts updated in real-time are employed, because they are more precise than forecasts for the day ***-ahead schedules are calculated using a two-stage robust mixedinteger optimization *** proposed control strategies were tested on a Chinese power network with wind power sources; the control performance was also validated numerically.

关键词： Automatic voltage control Model predictive control On-load tap changer Shunt capacitor/reactor Two-stage robust optimization Wind-power integration

Distribution of Mid-deeply Buried Sand-bodies and their Hydrocarbon Significance at Basin Margins: Case Study of the Paleogene in the Eastern Liuzan Area of the Nanpu Sag, Bohai Bay Basin, China

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1279-1294页

作者： CUI Lijie JIAN Shikai zhang boming XIE Xiongju LI Liang School of Geosciences China University of Petroleum(East China)QingdaoShandong 266580China Beijing Ultrado Resources Technology Inc. Beijing 100083China Research Institute of Exploration and Development PetroChina Jidong Oilfield CompanyTangshanHebei 063004China

The current research aims to unlock the temporal and spatial distribution of sand-bodies and their relationship with hydrocarbon accumulation in the mid-deep layer of basin margins, located in the eastern part of the Liuzan area of the Nanpu Sag, Bohai Bay Basin, China. Through this study, the main target interval of the area was divided into two fourthorder sequences. The lean sand mixed sedimentary belt with great importance in controlling hydrocarbon accumulation was identified through the comprehensive use of 3 D seismic data, logging data, lithological data and seismic inversion data. A detailed analysis of sand-body development characteristics and their role in controlling hydrocarbon accumulation was conducted. The results reveal that the study area mainly develops two distinct fan-delta lobes from the NE-trending sediment supply direction. Due to the relatively high influence of the lacustrine transgression event, the scale of the lean sand mixed sedimentary belt within the SQ1-1(the lacustrine transgressive systems tract) is relatively small, showing a relatively continuous distribution of sand bodies in the plane. Conversely, due to the relatively high impact of the lacustrine regression event, the scale of the lean sand mixed sedimentary belt developed within the SQ1-2(the highstand systems tract) is relatively large, the two east sets of fan-delta sedimentary systems being clearly separated. The lean sand mixed sedimentary belt formed a good lateral occlusion belt in favor of hydrocarbon accumulation. Through composite analysis of structural interpretation results, sand-body distribution and well test data, it is evident that the lean sand mixed sedimentary belt located in the structural high is not a favorable zone for hydrocarbon accumulation. In contrast, the wing of the high part of the structure is the zone of sand-bearing bodies and is a favorable zone of hydrocarbon accumulation.

关键词： lithological reservoirs sequence stratigraphy fan-delta sand-body correlation hydrocarbon accumulation