以卷积神经网络(CNN)为代表的深度学习算法在电力系统暂态电压稳定评估中开始得到应用,但其输入特征的构建方法及合理性验证未得到充分的研究.面对交直流系统暂态电压稳定评估,提出了一种适用于CNN的输入特征构建方法.首先,基于双阶段分区来降低输入特征的维度和冗余度,即先依据系统拓扑关系和地理位置约束给出初始分区结果,再以节点的暂态电压特征相似性进行聚类,得到降低维度和冗余度后的最佳分区方案;然后,在分区结果的基础上,考察影响交直流系统暂态电压稳定的关键因素,构建兼顾稳态特征量和多维度故障信息的输入特征;最后,将所构建的输入特征应用于CNN暂态电压评估模型,并采用实际电网数据进行验证.仿真结果表明,所提方法较传统特征选择方法具有更高的准确性.

随着风电、光伏等新能源占比的不断提高,电力系统的惯性逐步降低,受扰动后惯量响应引起的频率变化率增大,给频率安全稳定带来了威胁.受电网拓扑结构的影响,惯量响应的频率变化情况与功率扰动位置之间存在空间上的耦合特征.针对惯量响应在空间上的差异性,通过计算多机系统惯量响应模型的相对增益矩阵,量化了发电机惯量响应与有功功率扰动之间在空间上的耦合关系.仿真结果表明,相对增益能直观地表征不同位置和类型的功率扰动对发电机惯量响应的影响,对功率事故下低惯量系统的频率安全稳定分析与控制具有重要意义.

目前设计的微服务架构对客户需求响应能力较差,导致微服务架构工作过程损耗过大.为了解决上述问题,研究了一种新的自动化工程BIM+GIS云平台的微服务架构.采用自动化工程BIM+GIS云平台技术,对微服务架构进行深入研究,设计了自动化工程BIM+GIS云平台的微服务架构结构,微服务架构结构主要包括微服务节点、微服务控制接口以及电力云服务平台,采用负载均衡算法和先序遍历算法得出自动化工程BIM+GIS云平台微服务的构建流程.实验结果表明,研究的自动化工程BIM+GIS云平台的微服务架构能够及时响应客户端发送的服务请求,时效性较高,有效实现授权、负载均衡、注册等功能,提高了微服务架构的服务能力,有效解决了传统微服务架构服务质量低下、开发难度大、维护成本高、响应服务请求效率低、不易进行功能扩展等问题,可行性和稳定较好.

提出了一种暂态电压稳定性评估及其风险量化方法.首先,探讨卷积神经网络(CNN)与暂态电压稳定评估的关联性和匹配性,建立了基于CNN的暂态电压稳定评估模型.其次,在可信度框架下引入四元评估结构,可有效解决CNN在稳定边界识别上对时域仿真依赖的难题.然后,通过评估结果获取暂态电压稳定裕度,并将其与可信度相结合来构建风险函数,从而实现对暂态电压稳定的风险量化分级.实际电网算例分析结果验证了该方法的有效性.

In the typhoon-prone areas in southern China, the allocation of disaster prevention resources such as windproof reinforcement of power grid, is one of the key issues in the security defense of large power grid. The dynamic game model of defender-attacker-defender (D-A-D) is usually established to solve the problem. However, the existing D-A-D model does not consider the dynamic process of attacker’s attack order and operation mode adjustment. A multi-stage dynamic game model is thus proposed with consideration of the dynamic process of attacker’s attack order and dynamic process of power flow adjustment, and is transformed into an improved D-A-D model that can be solved by the column and constraint generation algorithm to obtain the optimal allocation of defense resources. The simulation results of the proposed model and algorithm on the IEEE39 node system show that the proposed model is more in line with the actual situation of power grid and the algorithm is more efficient.

机器学习中的人工神经网络已经逐渐用于电力系统自组织临界态辨识中.针对目前OPA模型等传统自组织临界辨识方法用时长或者只能给出电网演化的趋势性意见,而大部分神经网络方法都是基于已标记样本、忽略了未标记样本也能给训练提供有效信息的现状,结合半监督学习和径向基函数神经网络的优点,提出了基于半监督径向基函数神经网络的电网自组织临界态辨识方法,既可以利用未标记样本改善学习性能,又具备传统径向基函数神经网络的最佳逼近和全局最优的性能,其用时少、正确率高,满足在线辨识电力系统自组织临界态的要求;最后通过中国西部某区域电网的仿真分析证明了辨识方法的正确性和优越性,从而为实时预防电力系统连锁故障并提前做出针对性的预防控制提供理论基础和技术依据.

针对多端常规直流和不同混合方式的多端混合直流在交流系统故障情况下的不同响应特性,本文介绍了多端直流输电系统一次系统以及控制系统的机电暂态建模方法,以三端直流输电系统为例,构建一送端两受端的三端直流输电系统,考虑LCC-LCC-LCC、LCC-VSC-LCC、LCC-VSC-VSC 3种组合形式,建立了其对应的仿真模型,研究对比了不同的多端直流组合方式在不同电压跌落程度的交流系统故障情况下的响应特性。对比结果表明,在逆变侧采用VSC换流器可以有效的减少逆变侧因为交流系统故障发生换相失败导致直流系统不能进行有效的功率传输的情况;两个逆变站同时采用VSC换流器可以更大程度的发挥VSC换流器不会发生换相失败的优势,最大限度的保证直流功率的传输;同时,VSC换流器作用的充分发挥需要多端直流输电控制系统的紧密配合。

大力发展风电已成为我国的能源战略,对未来的经济发展起到关键作用。不同地区经济发展水平、电源电网结构、用电成本和电价水平均存在差异,量化评估风电接入后的综合经济性有助于指导不同地区风电的规划和建设。本文提出了一种大规模风电接入的综合经济性评估方法,分别从6个维度进行了分析,包括系统运行成本、煤耗与排放、常规机组利用小时数、风电补贴成本、电网公司运营收益以及煤电上网电价。最后,以某省级电网为例,评估该区域大规模风电接入下的综合经济性,验证了该评估方法的有效性。

近年来极端天气事件频繁发生,黑启动电源成为电网大停电后能否快速恢复的关键,对于缺乏抽水蓄能机组和水电机组的地区电网,文章提出有选择地对区域内的燃气-蒸汽联合循环机组进行黑启动改造,优化黑启动电源布点方案。文章结合极端天气对电网的影响,定义了线路恢复风险,建立了以最小化保底网架恢复时间和线路恢复风险为目标的黑启动电源布点双目标优化模型,在找出方案非劣解的基础上应用推广理想点法求得最终黑启动电源布点方案,并通过东莞地区电网的算例验证了该方法的有效性。

含多直流馈入的受端电网发生大停电后,充分发挥直流系统启动后的调控能力是加快负荷恢复进程的重要手段,同时对系统恢复控制提出了更高的要求.在此背景下,提出了一种多直流馈入系统功率调控与受端系统机组出力恢复协调优化方法.首先,从直流系统逆变站的功率调控特性和多直流馈入系统与送/受端交流系统的交互作用这2个层面分析多直流馈入系统的功率调控特性,并建立相应的功率调控约束模型;然后,以机组爬坡时间和直流系统功率调控时间最短为目标,综合考虑直流系统、送/受端系统的约束条件以及常规发电机组的恢复运行约束等因素,建立直流馈入量调整模型,计及系统功率平衡、电压和频率安全、旋转备用等约束,构建多直流馈入受端系统的机组出力优化模型.在此基础上,将该问题建模为双层混合整数线性规划模型,实现传统机组出力和各直流传输量的协调优化,最小化机组出力调整时间,并达到避免直流传输量小幅调整的调度目标.最后,以含多直流馈入的IEEE 30节点、IEEE 118节点系统以及含多风电场的IEEE 30节点系统为算例验证所提模型的有效性.

多馈入高压直流输电系统(line commutated converter based high voltage direct current,LCC-HVDC)的新增直流落点选择问题需要考虑多回直流间的交互作用影响.为兼顾电网稳定性与经济性,本文建立包括多馈入短路比(multi infeed short circuit ratio,MISCR)、直流换相失败风险以及系统抵御N-1故障所需的动态无功补偿容量的指标体系.在此基础上,采用归一化处理和线性加权法实现落点方案的比选.最后,结合乌东德直流工程,将本文提出的直流落点优选方案应用于实际算例.

基于电压源换流器(VSC)的柔性直流输电(HVDC Flexible)技术在能源领域已经得到越来越多的重视和应用,是新一代高压直流输电技术.由于近年来智能电网技术的发展和应用的需要,柔性直流输电技术在国内外得到普遍的重视.通过对柔性直流输电系统在不同控制模式下某电网异步联网后的运行情况进行分析,得出不同条件对于系统的影响.通过对系统采用的柔性直流系统的无功控制策略进行分析,主要包括对柔性直流系统与AVC(电压无功控制)的协调控制策略、系统级无功控制策略的分析研究,柔性直流系统的保护部分设计原则是按面向物理或逻辑对象的原则进行功能配置,不同对象的功能之间尽可能少地交换信息,某一对象异常不影响其它对象功能的正常运行,从多个方面对系统提出了具体控制措施.最后阐述了某省应用柔直背靠背异步联网的具体方案,通过柔性直流输电不同无功控制模式下某电网异步联网后的交流系统稳定情况,电网暂态电压运行情况以及系统稳定情况进行对比,并从电压稳定性、暂态电压敏感性等多个方面具体分析,得出不同无功控制模式对于电网运行的影响.

Controlled islanding represents an emergency control approach through dividing a large power system into several small ones by employing real-time information of the power system concerned. Implementation of controlled islanding at the appropriate time can prevent the power system from cascading failures,and thus large-area power outages can be avoided. Given the above background,a method to determine the optimal timing of controlled islanding is presented by utilizing data from the wide area measurement system(WAMS)concerned and combination prediction. Specifically,WAMS is employed to attain power angles and operating frequencies of generators in real time,and a combined linear prediction algorithm is used to forecast disturbed trajectories of generators,and hence the power system can be islanded before that operating frequencies of generators go beyond their limits. In this way, the emergency shutdown of generators can be avoided and the operation stability of each island after controlled islanding maintained. Moreover,a combined linear prediction algorithm is presented based on the well established auto-regressive moving-average (ARMA) algorithm and Kalman filter algorithm so as to achieve better prediction performance. Finally,the proposed method is demonstrated by the IEEE 39-bus test system.

A smart substation, which represents the development trend of advanced substation technology, is an important part of a smart grid.The configuration of smart substation could have significant impacts on the secure and economic operation of the distribution system concerned, and is an important problem to be addressed.Given this background, this paper studies the intelligent upgrading strategy of substations in power distribution system with reliability indices considered.First, we construct the intelligent upgrading optimization model of substations in power distribution system to minimize the upgrade costs of existing conventional substations and the interruption costs of customers, with considering the constraint conditions that two reliability indices including the system average interruption duration index (SAIDI) and average energy not supplied (AENS) don`t exceed a given threshold.Secondly, we present a fault clearing model for power distribution system and propose an accurate assessment method for the user`s outage time.Then, we linearize the user`s outage time and outage cost function to obtain a mixed integer linear programming model for the intelligent upgrading strategy of substations, which is solved by efficient commercial solvers.Finally, the IEEE RBTS-Bus 4 distribution power system and an actual medium voltage distribution network in Denmark are served for demonstrating the basic characteristics of the presented method.

To solve the problem of the optimal position of new HVDC access to multi-infeed HVDC system,first the paper introduces the structure and characteristics of voltage source converter based high voltage direct current(VSC-HVDC),and expounds the advantages of VSC-HVDC over line commutated converter based high voltage direct current(LCC-HVDC). Then on the basis of analyzing the necessity of research on the optimal position of VSC-HVDC and fully considering the impact of the new HVDC on the stability of AC-DC system,the paper establishes a index evaluation system composed of multi-infeed short circuit ratio(MISCR), HVDC commutation failure risk and receiver system instability risk,and gets a composite indicator by adding indicators linearly according their weights after standardizing the indicators. Based on which the optimal position is selected from alternatives based on the composite metrics. Finally,the proposed method is applied to the practical example to obtain the optimal position of the new HVDC, and improving the safety and stability of the receiver system.

This paper analyzes influence of shunt compensation capacitor and charging power of the line on calculation result of short‐circuit current in theory and selects calculation model and data of maximum operational mode in summaer in some regional power grid for simulating analysis .Simulation results indicate that calculation result of short‐circuit current may be relatively small when considering influence of shunt capacitor and charging power which verifies changing laws from theoret‐ical analysis .It also analyzes and finds out power plants and stations with larger deviations of calculation results and reasons for deviations .Finally ,it suggests electric power departments to pay attention to coordination and cooperation when carry‐ing out power grid planning and operation so as to avoid short‐circuit current exceed the standard in practical operation when making calculation on short‐circuit current without considering shunt capacitor and charging power and promote integrating degree of theoretical calculation value and actual operational value .

According to the Electricity Accident(Event) Investigation Procedures of China Southern Power Grid(pilot) and the Guide on Operational Risk Evaluation of China Southern Power Grid ,a set of power system outage risk assessment index is proposed for calculating the risk in terms of electric power security accident(event),based on which and combined with the OPA model,a method of power system outage risk assessment is proposed. Simulation is carried out for a 500 k V power grid and results show that,the identified weak areas agree with its operational experiences,verifying the correctness of the proposed indexes and method.

With the maturity of fast cut back(FCB)technology of large-scale thermal power units,it is now possible to use the FCB unit as the black-start power supply after a blackout.Planning the location of FCB units should take the engineering practice into account.The properties of the optimized placement scheme of FCB units are derived with the graph theory method.The successive property of the optimal placement scheme with known active point numbers is proved.Then the recursive method is presented for optimizing the placement scheme of FCB units.An economic index is then developed.Based on the calculating results of the recursive method,a placement scheme of FCB units meeting both safety and economic requirements can be obtained according to the economic index.Example analysis results show that the recursive method is more efficient and has a higher robustness than the conventional method.Meanwhile,with reference to the economic index,it can be seen that the calculation results can be used as a basis for black-start power supply planning.

This paper mainly focusing on the naming norms of power plants, sub-stations and transmission lines. With the large expansion of Guangdong power grid, it requires updating and extending the traditional naming norm, even forming new one to adapt to the changing management environment and great changes. By a spirally progressing procedure, including survey, objective design, guidance of practice and improvement, this paper finally proposes new naming norms for sub-stations and transmission lines in Guangdong Power Grid, which offers great help for electrical device management.

广东电网以大型火电快速切回(FCB)机组为黑启动电源,于2013年7月4日成功进行了空充500 k V输电线路的试验。高压长距离线路在空充过程中容易产生自励磁、过电压等现象,导致黑启动失败,因此对机组的自励磁特性进行了理论分析,分析结果表明试验过程中机组不会出现自励磁现象。基于理论分析提出了自励磁工程判据;并对线路的过电压特性进行了仿真计算,计算结果表明,试验过程中各测量点的电压均满足国标要求。