电动汽车集群内的递阶分散最优充电方法

电动汽车未来有望以集群（例如大型充电站内的电动汽车）形式参与电网调度。收到电网下发的集群优化充电调度指令后,集群代理需优化集群内的电动汽车充电功率以追踪电网指令。该追踪问题是一个大规模的优化问题,难于集中式求解。提出一种递阶分散优化算法求解该问题。集群代理下发协调信息,各电动汽车根据协调信息分布式地优化自身充电功率,并向代理返回迭代信息,通过迭代求得问题的最优解。为进一步提高计算效率,对集群代理和单辆汽车的优化子问题进行了深入研究和算法改进。通过数值实验发现所提方法具有很快的计算速度,尤其适用于求解大规模电动汽车集群内的追踪问题。     

DEH控制系统的改进与完善

介绍了DEH-ⅢA系统的构成和在300MW机组的应用情况,分析了应用中出现的问题,提出了行之有效的解决办法。     

电网突发事件的网络舆情预警方法

为了实现电网突发事件网络舆情的精确预警,运用信息安全风险评估理论分析得出了导致电网突发事件网络舆情的各类影响因素,并设计了基于支持向量机的网络舆情预警指标体系。将预警指标体系的构造过程抽象为分类问题,将各类影响因素作为分类问题的输入量,预警等级作为分类问题的输出量,并利用支持向量机求解分类问题,有效地避免了传统方法中主观性较强的缺点。最后基于2012年4月10日深圳停电事件网络舆情监测数据的验证性实验,表明该方法在运算耗时和预警精度等方面的性能优异。     

35kV直配电系统存在的问题及解决措施

分析了35kV直配电系统运行中存在的主要问题,并提出了具体解决措施,通过实施效果较好,达到了减少事故影响范围及完善35kV直配电系统的目的.     

双调度交换机组网运行的安全保障对策

随着电网的不断发展,对电力调度通信稳定性的要求越来越高.2007年,福建电力系统省调和地调等一些重要调度部门和单位,已经采用双调度交换机组网的运行方式,在避免整个调度通信系统出现瘫痪状态、减少故障恢复时间和减轻运行维护压力等方面具有重要的优势.由于双调度交换机组网运行系统较为复杂,双调度交换机组网技术仍有一些问题需要完...     

南方电网开展合同能源管理的实践

通过对南方电网五省区合同能源管理发展过程中遇到的资金、技术和政策障碍的研究,提出了南方电网五省区合同能源管理的发展模式建议,旨在推动合同能源管理在南方电网得以深入发展,并进一步广泛推行。     

An extension of the FFT‐based algorithm for the match‐count problem to weighted scores

The match‐count problem on strings is the basic problem of counting the matches of characters between two strings for every possible alignment. The problem is classically computed in O (σ n log m ) time using a fast Fourier transform (FFT) for two strings of lengths m and n (m ≤ n ) over an alphabet of size σ . This paper extends the target of this FFT‐based algorithm to a weighted version of the problem, which computes the sum of similarities between characters instead of the number of matches. The algorithm extended in this paper can solve the weighted match‐count problem in O (dn log m ) time by mapping characters to numerical vectors of dimensionality d . This paper also evaluates the usefulness of the extended algorithm by applying it to plagiarism detection in documents. The experimental results show that the proposed algorithm is applicable to general vector representation of words and that the obtained plagiarism detection method can extremely reduce the processing time with a slight decrease of accuracy from the method based on the normal match‐count problem.     

电工电子学开放性实验教学探索

开放性实验教学是指实验时间、空间、教学内容和方法等都是开放的。学生可以随时进入实验室,进行实验设计和调试,并最终独立完成实验。开放性实验能够调动学生学习的主动性和独立思考的能力,激发学生参与科研的兴趣和创新意识,对学生树立理论联系实际的理念,培养分析问题解决问题的能力有着重要的作用。本次进行的数字钟电路设计与实现实验,使我们首次学会自己动手设计实验方案,制定实验步骤,实施实验过程,讨论实验结果,在查阅文献资料的过程中学习和巩固理论知识;同时也锻炼了我们的动手能力,培养了我们发现问题、解决问题和团结协作的能力。     

Modeling and analysis of strategic forward contracting in transmission constrained power markets

Taking the effects of transmission network into account, strategic forward contracting induced by the interaction of generation firms’ strategies in the spot and forward markets is investigated. A two-stage game model is proposed to describe generation firms’ strategic forward contracting and spot market competition. In the spot market, generation firms behave strategically by submitting bids at their nodes in a form of linear supply function (LSF) and there are arbitrageurs who buy and resell power at different nodes where price differences exceed the costs of transmission. The owner of the grid is assumed to ration limited transmission line capacity to maximize the value of the transmission services in the spot market. The Cournot-type competition is assumed for the strategic forward contract market. This two-stage model is formulated as an equilibrium problem with equilibrium constraints (EPEC); in which each firm's optimization problem in the forward market is a mathematical program with equilibrium constraints (MPEC) and parameter-dependent spot market equilibrium as the inner problem. A nonlinear complementarity method is employed to solve this EPEC model.     

我国风力发电市场前景及存在的问题

近年来,全球的风能发电市场发展迅速,我国也在大力发展风力发电,提升了风能发电在能源供给中的比重。目前,我国风力发电累计装机容量已居世界前列。针对我国风力发电市场及其相关产业目前的发展状况,同时对一些存在的问题作了阐述。旨在使我国的风力发电行业整体有一个合理,健康和可持续的发展。