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CSEE Journal of Power and Energy Systems 2021年第1期7卷 114-127页

作者： Puyu Wang Shihua Feng Pengcheng Liu ningqiang jiang Xiao-Ping Zhang School of Automation Nanjing University of Science&Technology(NUST)Nanjing 210094China School of Engineering University of BirminghamEdgbastonBirmingham B152TTUnited Kingdom

Controllability of DC current/power flow is essentialin multi-terminal HVDC (MTDC) grids, particularly for theMTDC grids in a meshed topology. In this paper, consideringmeshed MTDC (M2TDC) grids with the installation of twoline/multi-lineDC current flow controllers (CFCs), a small-signalmodel of the DC CFCs integrated M2TDC grids is derived,studying the impact of the power losses of the DC CFC andtheir influence on the analysis of energy exchanges. The systemstability analysis is analysed using the Nyquist diagram, which ismore suitable for analyzing complex nonlinear systems with morecompact and reliable indicators of stability in comparison withgain/phase margins shown in the Bode diagram. In addition, aselection method of the interconnected capacitor of the DC CFCis proposed under different operating conditions. The impact ofthe switching frequencies of the DC CFC on the control ranges ofthe DC current flows is analyzed. The effectiveness of the Nyquistanalysis and the capacitance selection method is verified bysimulation studies using PSCAD/EMTDC. The obtained control ranges of the DC CFC with different switching frequenciesand capacitances would be useful for practical engineeringapplications.

关键词： Capacitance selection method control ranges DC current flow controller(CFC) meshed multi-terminal HVDC(M2TDC)grid Nyquist stability analysis small-signal modelling switching frequencies

Impact of the PV Location in Distribution Networks on Network Power Losses and Voltage Fluctuations with PSO Analysis

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CSEE Journal of Power and Energy Systems 2022年第2期8卷 523-534页

作者： Puyu Wang Fangyu Liang Jinyuan Song ningqiang jiang Xiao-Ping Zhang Ling Guo Xinxin Gu School of Automation Nanjing University of Science&Technology(NUST)Nanjing 210094JiangsuChina School of Engineering University of BirminghamEdgbastonBirmingham B152TTUnited Kingdom Nanjing GWDR Relays Technologies Co. Nanjing 210032JiangsuChina

Increased grid integration of photovoltaic(PV)has aggravated the uncertainty of distribution network *** a distribution network with PV,the impact of the PV location on the network power losses and voltage fluctuations is investigated with analytical derivations reflected by the line *** approaches of the PV location with consideration of two aspects,i.e.,minimum network power losses and minimum voltage fluctuations,are analyzed.A particle swarm optimization(PSO)algorithm is used to synthesize an optimal compromised solution so as to determine the PV location.A 10 kV distribution network with one PV is established on the time-domain simulation environment PSCAD/*** simulation results justify the theoretical analysis and indicate that when the active power of the PV is more/less than twice that of the overall loads/end loads,the network power losses and node voltage fluctuations are both minimum when the PV is integrated into the head/tail end of the *** the active power of the PV is between the above two conditions,nodes t/f can be identified for the integration of the PV between the head/end nodes of the network to achieve the minimum network power losses/voltage fluctuations,*** effectiveness of the proposed optimization approach is verified and can provide a reference for selecting the PV location in the distribution network.

关键词： Distribution network network power losses particle swarm optimization(PSO) PV location voltage fluctuations

Transient Stability Analysis Based on the Sensitivity of Trajectory Length

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Wuhan University Journal of Natural Sciences 2009年第2期14卷 169-173页

作者： jiang ningqiang HUANG Chao CAI Weifeng School of Automation Nanjing University of Science and Technology Nanjing 210094 Jiangsu China

The length of the trajectory is proposed as a function for the employment of the sensitivity analysis method in power system transient stability analysis. Its sensitivity to the faultclearing time is about 10 times higher than that of the energy function or the distance function. The integrating time is reduced to less than 3 s while the accuracy is maintained. It can also be used to provide parameter limits. Simulations on the WSCC 4 machine system and the New England system verify the effectiveness of sensitivity of trajectory length in transient stability analysis.

关键词： power system transient stability sensitivity analysis

考虑静止无功补偿器限幅特性的临界清除时间启发式算法

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南京理工大学学报 2017年第6期41卷 725-729页

作者：江宁强王晓南京理工大学自动化学院江苏南京210094

为克服静止无功补偿器(SVC)的限幅特性给电力系统暂态稳定分析带来的困难,本文基于短路引起的暂态过程中SVC导纳变化的特征,提出了1种故障临界清除时间(CCT)的启发式算法。计算故障轨线的投影轨线,并沿该轨线用容性导纳变化率确定CCT。... 详细信息

为克服静止无功补偿器(SVC)的限幅特性给电力系统暂态稳定分析带来的困难,本文基于短路引起的暂态过程中SVC导纳变化的特征,提出了1种故障临界清除时间(CCT)的启发式算法。计算故障轨线的投影轨线,并沿该轨线用容性导纳变化率确定CCT。由于不需要计算暂态能量、主导不稳定平衡点和故障后轨线等,因此该方法计算量小,暂态稳定分析效率高。对1个三机系统的算例分析结果表明,该方法得到的CCT相对误差小于10%。

关键词：静止无功补偿器限幅特性临界清除时间暂态稳定电力系统

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考虑SVC的电力系统直接法稳定性分析

智能电网 2017年第3期5卷 254-259页

作者：尤彬彬江宁强南京理工大学自动化学院江苏省南京市210094

静止无功补偿器(static var compensator,SVC)等基于电力电子技术的柔性输电元件在电力系统中的应用不断增加,为电力系统直接法暂态稳定分析提出了新的研究课题。阐述含SVC的电力系统能量函数的构造,其中分别考虑了假定SVC母线电压恒定... 详细信息

静止无功补偿器(static var compensator,SVC)等基于电力电子技术的柔性输电元件在电力系统中的应用不断增加,为电力系统直接法暂态稳定分析提出了新的研究课题。阐述含SVC的电力系统能量函数的构造,其中分别考虑了假定SVC母线电压恒定和忽略SVC控制器动态这两种情况。在此基础上,运用势能界面法(potential energy boundary surface method,PEBS)法计算故障临界清除时间,通过一个两机系统的时域仿真验证计算结果的有效性。计算结果表明,对于所考虑的两种情况,直接法能够用于含SVC的电力系统暂态稳定分析,克服了文献方法的不足。

关键词：静止无功补偿器能量函数暂态稳定直接法

交直流电力系统暂态过程中同步发电机阻尼转矩系数的计算

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电气技术 2015年第8期16卷 11-14,33页

作者：吴学苹江宁强南京理工大学自动化学院电气工程系南京210094

阻尼转矩是电力系统动态稳定研究中的一个重要概念。发电机采用简化模型时,阻尼转矩系数的取值尚缺乏理论依据。本文利用多项式逼近方法计算了交直流电力系统中同步发电机的阻尼转矩系数,并分别采用本文方法和小扰动方法计算出机电暂态... 详细信息

阻尼转矩是电力系统动态稳定研究中的一个重要概念。发电机采用简化模型时,阻尼转矩系数的取值尚缺乏理论依据。本文利用多项式逼近方法计算了交直流电力系统中同步发电机的阻尼转矩系数,并分别采用本文方法和小扰动方法计算出机电暂态充分衰减后的阻尼转矩系数,以校验本文方法的正确性。计算结果表明,暂态过程中,同步发电机的阻尼转矩系数是变化的。对于稳定系统,机电暂态充分衰减后,本文方法计算结果与小扰动方法计算结果一致。

关键词：交直流电力系统多项式逼近法暂态过程阻尼转矩系数

Impacts of the annual cycle of background SST in the tropical Pacific on the phase and amplitude of ENSO

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 12-17页

作者： Song jiang Congwen Zhu Ning jiang State Key Laboratory of Severe Weather(LASW) Chinese Academy of Meteorological SciencesBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina

The dominant annual cycle of sea surface temperature(SST)in the tropical Pacific exhibits an antisymmetric mode,which explains 83.4%total variance,and serves as a background of El Niño-Southern Oscillation(ENSO).However,there is no consensus yet on its anomalous impacts on the phase and amplitude of *** on data during 1982-2022,results show that anomalies of the antisymmetric mode can affect the evolution of ENSO on the interannual scale via Bjerknes feedback,in which the positive(negative)phase of the antisymmetric mode can strengthen El Niño(La Niña)in boreal winter via an earlier(delayed)seasonal cycle transition and larger(smaller)annual *** magnitude of the SST anomalies in the equatorial eastern Pacific can reach more than±0.3◦C,regulated by the changes in the antisymmetric mode based on random sensitivity *** reveal the spatial pattern of the annual cycle associated with the seasonal phase-locking of ENSO evolution and provide new insight into the impact of the annual cycle of background SST on ENSO,which possibly carries important implications for forecasting ENSO.

关键词： Annual cycle SST anomaly Antisymmetric mode ENSO

直流功率调制在交直流系统中抑制低频振荡的研究

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智能电网 2017年第7期5卷 665-670页

作者：黄畅想江宁强袁翌晖南京理工大学自动化学院江苏省南京市210094

随着电网规模的不断扩大,高压直流输电在远距离、大容量的输电中具有明显优势,已成为电网的重要组成部分。该文以交直流多区域互联系统中区域间低频振荡问题为研究对象。以具有交直流并行联络线的四机两区域系统为模型,采用Prony分析法... 详细信息

随着电网规模的不断扩大,高压直流输电在远距离、大容量的输电中具有明显优势,已成为电网的重要组成部分。该文以交直流多区域互联系统中区域间低频振荡问题为研究对象。以具有交直流并行联络线的四机两区域系统为模型,采用Prony分析法和时域仿真方法,利用直流功率调制技术对低频振荡现象进行研究。仿真表明,直流功率调制可以增强系统的阻尼,抑制电网区域间的功率振荡,而且可以提高交直互联系统的暂态稳定性。

关键词：直流功率调制低频振荡暂态稳定 Prony法

含SVC电力系统的IPEBS法暂态稳定分析

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电气工程学报 2023年第3期18卷 277-284页

作者：胡继磊刘雪粲江宁强葛晨阳邱殿成国网江苏省电力有限公司连云港供电分公司连云港222100 国网江苏省电力有限公司徐州供电分公司徐州221000 南京理工大学自动化学院南京210094

研究了含静止无功补偿器(Static var compensator,SVC)的多机电力系统的暂态稳定性。首先建立了含SVC的多机电力系统模型,并基于等效负荷概念,构造出含SVC的电力系统的能量函数,验证了能量函数在故障后单调下降的特性。将SVC势能用并网... 详细信息

研究了含静止无功补偿器(Static var compensator,SVC)的多机电力系统的暂态稳定性。首先建立了含SVC的多机电力系统模型,并基于等效负荷概念,构造出含SVC的电力系统的能量函数,验证了能量函数在故障后单调下降的特性。将SVC势能用并网电压和功率表示,克服了SVC模型复杂给构建能量函数带来的困难。采用提出的能量函数,在修改的3机9节点系统和10机39节点系统中验证了迭代势能界面法(Iterative potential energy boundary surface,IPEBS)的有效性。计算结果表明,与时域仿真法相比较,所得故障临界清除时间(Critical clearing time,CCT)的误差较小。

关键词：静止无功补偿器暂态稳定能量函数迭代势能界面法

Effects of carbon content on the microstructure and tensile properties of a low-density steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 391-401页

作者： Yongxuan Shang Mingyu Fan Shuyong jiang Zhongwu Zhang Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China State Key Laboratory of Metal Material for Marine Equipment and Application Iron&Steel Research Institute of Ansteel Group CorporationAnshan 114009China

Carbon can change the phase components of low-density steels and influence the mechanical *** this study,a new method to control the carbon content and avoid the formation ofδ-ferrite by decarburization treatment was *** microstructural changes and mechanical characteristics with carbon content induced by decarburization were systematically ***-Jaoul(C-J)analysis was employed to examine the work hardening characteristics during the tensile *** decarburization by heat treatments,the carbon content within the austenite phase decreased,while Mn and Al were almost unchanged;this made the steel with full austenite transform into the austenite and ferrite dual ***,(Ti,V)C carbides existed in both matrix phase and the mole fraction almost the *** addition,the formation of other carbides *** loss induced a decrease in strength due to the weakening of the carbon solid *** the steel with the single austinite,the deformation mode of austenite was the dislocation planar glide,resulting in the formation of *** the dual-phase steel,the deformation occurred by the dislocation planar glide of austenite first,with the increase in strain,the cross slip of ferrite took place,forming dislocation cells in *** the late stage of deformation,the work hardening of austinite increased rapidly,while that of ferrite increased slightly.

关键词： low-density steels carbon content decarburization strengthening mechanisms work hardening behavior