【作者】 马丽叶；

【导师】 卢志刚；

【作者基本信息】 燕山大学 ， 电力电子与电力传动， 2012， 博士

【摘要】 在新的电力体制下，配电网经济运行成为电力系统面临的重大课题之一。对配电网运行的经济性进行评价，不仅能够对现有配电网的运行状况进行考核，还可以找出电网运行中的薄弱环节，对配电网运行、规划、降损节能具有重要的现实意义。目前对配电网评价的研究很多，但涉及到经济性的大部分是关于电网规划方案的经济性或电网技术改造的效益评估。为此，本论文深入研究了配电网运行经济性评价工作中目前存在的问题，并提出了相应的解决方法，同时通过算例验证了所提方法的有效性。本论文的主要研究内容如下：首先，为建立合理的配电网运行经济性评价指标体系，提出了一种基于群灰色模糊聚类的闭环建立方法。在专家确定初始主观评价指标体系的基础上，利用改进的模糊聚类法对不确定指标进行分类，然后利用群灰色关联度法确定待筛选指标，并运用证据理论融合待筛选指标的专家可信度，最后依据可信度融合结果对待筛选指标进行闭环调整，消除了冗余指标。算例结果验证了该指标建立方法的有效性。其次，提出了一种基于D-S(Dempster-Shafer)证据理论的配电网运行经济性评价指标权重闭环计算方法。首先邀请专家给出了指标主观权重，并剔除偏离程度大的专家意见，利用改进的证据理论确定专家主观权重。若主观权重证据不充分，则需进一步求其客观权重，并利用斯皮尔曼方法检验主客观权重的相关性，实现了对该算法的闭环调整，直至主客观权重满足一致性要求，进行主客观权重融合最终得到更符合实际的权重结果。接着，基于上述已确定的配电网运行经济性评价指标体系和权重，建立了配电网运行经济性的模糊综合评价模型，并结合专家意见及配电网实际运行情况给出了各评价指标的隶属度函数模型及各模型参数。利用模糊综合评价方法计算求得各指标的隶属度、权重及得分，对配电网运行的经济性进行了系统、科学的评价。然后，针对配电网运行经济性评价的多维多层次和不确定性，提出一种基于区间数的城市配电网运行经济性模糊综合评价模型。利用改进的区间层次分析法计算指标权重，降低权重主观性的同时避免了区间数发散的问题。考虑到不同地区配电网的特点，隶属度函数参数采用区间数形式，同时定义了区间数中心的概念，构建了基于区间梯形隶属度函数的模糊综合评价模型，并利用区间符合度确定综合得分区间数的等级水平。实例分析验证了该模型的可行性。最后，建立了基于离散BCC(Bacterial Colony Chemotaxis)优化算法的配电变压器优化配置模型。制订了配电变压器的替换原则，给出了以损耗模糊区间数、停电损失费用和安装及调试费用为综合费用的区间形式的目标函数。考虑到负荷的不确定性，利用基于模糊区间的前推回推潮流算法，计算变压器替换后整个配电网的损耗变化量，最后运用离散BCC优化算法对配电变压器的替换进行寻优，给出配电变压器的最优配置方案。更多还原

【Abstract】 In the new electric power institution, the distribution network economic operation isan important research topic. To evaluate the distribution network economic operation cannot only access the existing situation of distribution network, but also find out its weaklink. It has an important practical significance for distribution network economicoperation, planning and energy conservation. At present, there are many studies on theevaluation of distribution network, but most of them are about the economics of networkplanning or network transformation benefit analysis. Therefore, this paper delves into theexisting problems in the evaluation of distribution network economic operation, andprovides the corresponding methods, at the same time, testifies the effectiveness of theproposed methods by simulation examples. The major contents of this paper arepresented as follows:Firstly, in order to establish the reasonable evaluation index system of distributionnetwork economic operation, a closed-loop method based on group gray fuzzy clusteringis proposed. Based on the initial subjective index system given by expert, the fuzzyclustering is improved to objectively classify the uncertainty index. Then by using thegroup grey relational analysis method, the indexes to be selected are determined, and theexpert reliability of the index to be selected is fused by D-S evidences theory. Finally,according to the fusion results, the closed-loop adjustment of indexes to be selected isperformed to eliminate the redundant indexes. The effectiveness and practicability of theproposed index system are verified by calculation example.Secondly, a closed-loop weighting determination method based on D-S evidencestheory is proposed. First of all, the subjective index weights from experts are collectedand the conflict expert opinions are rejected, and by using the improved D-S evidencestheory, the subjective weight is determined. Then if the subjective weight is insufficient,the objective weight needs to be worked out further. And the Spearman method is used totestify and ensure the consistent of the subjective and objective weight, which achievedthe closed-loop adjustment of the algorithm. The eventual weight that can meet the requirement of objective and subjective is calculated based on the above results.Thirdly, based on the above determined evaluation index system and weight ofdistribution network economic operation, its fuzzy comprehensive evaluation model isestablished. And combining the expert opinions and actual operation of distributionnetwork, the membership function and the model parameters for each index are given.Then, by using the fuzzy comprehensive evaluation method, the membership of the index,the index weight and index scores are acquired. Meanwhile, the economy of distributionnetwork operation is evaluated systematically and scientifically.Fourthly, in view of the multi-dimensional and multi-level evaluation factorsincluding uncertainties in the evaluation of distribution network economic operation, afuzzy comprehensive evaluation model based on interval number is proposed. To lowerthe subjectivity of weight as well as avoid the divergence of overall score, an improvedInterval AHP is used to calculate the index weight. Then taking the different characters ofdistribution network in the different regions into account, interval trapezoidalmembership function is used and the concept of the center of the interval number isdefined to build the evaluation model. Finally, the rating level of overall score intervals isdetermined by the concept of interval conformity degree. And the conclusive result ofcase analysis demonstrates the feasibility of the proposed method.Finally, a model based on discrete BCC for optimal allocation of distributiontransformer is established. Firstly, the replacement principle of distribution transformer isformulated, and an interval objective function is given which concludes fuzzy intervalloss costs, power loss costs and installation debugging costs. Taking the uncertainties ofload condition into consideration, the loss variation of the entire distribution network iscalculated by using the forward-backward power flow algorithm based on fuzzy intervalmethod. Then, the replacement of distribution transformers is optimized by using discreteBCC, which provides the optimal configuration of distribution transformer.更多还原