城市电网规划是城市总体规划的重要组成之一，其水平和规划质量将直接影响供电 区域电网的三个指标，安全性、可靠性和经济性。随着城市化建设快速发展，城市负荷 密度急速增长，为避免不必要的资源浪费和经济损失，需要进行科学合理的规划，提高 城网规划水平。 城市配电网的中压改造是一项适应我国城市现代化发展需要、建设资源节约和环境 友好型电网的重要战略决策。本文结合国内外对中压电网的研究现状，对 10kV 与 20kV 中压配电等级电网的供电能力、功率损耗、电压质量等指标进行了比较分析，研究了发 展建设 20kV 配电等级的技术可行性和必要性；遵循电网升压改造规划原则，采用组合 预测的方法对郑州新区进行中长期负荷预测，制定了郑州新区中压配电网应用 20kV 的 规划方案，通过分析研究，验证了 20kV 中压配电等级的技术可行性和经济优越性。 关键词，负荷预测；城市电网规划；中压配电网；升压改造$%675$&7 III THE STUDY ON POWER SUPPLY METHOD OF THE 20kV DISTRIBUTION NETWORK IN CITY MEDIUM VOLTAGE ABSTRACT The urban power grid planning is one of the most important parts of the urban master planning, the quality of the grid planning will directly influence the index of power supply as security, reliability and economy. With the urbanization developing rapidly, the urban load increases quickly, to avoid unnecessary wasting of resources and economic losses, a scientific and reasonable planning of the urban power grid is necessary. The boost transformation of the urban medium voltage distribution grid is one of the most important decisions, which can fit the need of the urban modern development of our country and build the resource-efficient and environment-friendly type power grid. This thesis that the actuality of the urban power grid which considering the study status at home and abroad, contrasting the index of power grid of 10kV and 20kV as power supply capacity, power loss, voltage quality and so on. Then analyzing the technical feasibility and necessity of building the power distribution grid of 20kV with keeping to the principle of the boost transformation of power grid; According to the principle of power grid voltage booster, the medium and long term load forecasting of Zhengzhou new district is carried out by using the combined forecasting method, and researching on applying the medium voltage distribution grid of 20kV to the new district of zhengzhou city. Through analysis and research, the technical feasibility and economic superiority of 20kV medium voltage power distribution system are verified. KEY WORDS: Load prediction, Urban power grid planning, Urban medium voltage distribution grid, Boost transformationI 目 录 摘要.........................................................................................................................................I ABSTRACT............................................................................................................................. III 1 绪论........................................................................................................................................ 1 1.1 本文的研究背景及意义 ................................................................................................. 1 1.2 国内外 20kV 配电研究现状 .......................................................................................... 2 1.2.1 国外 20kV 配电研究情况......................................................................................... 2 1.2.2 国内 20kV 配电研究情况......................................................................................... 3 1.3 郑州电网现状 .................................................................................................................. 4 1.4 中压配电电压等级优化的基本思路 .............................................................................. 4 1.5 本文的主要工作 .............................................................................................................. 5 2 电网中压配电等级现状与升压分析..................................................................................... 7 2.1 电网中压现状与升级改造的相关问题 .......................................................................... 7 2.1.1 10kV 优势与局限性.................................................................................................. 7 2.1.2 20kV 中压配电电压等级优势 ................................................................................. 7 2.2 经济技术分析模型 ......................................................................................................... 8 2.2.1 初期静态投资费用计算模型.................................................................................... 8 2.2.2 电能总损耗计算模型.............................................................................................. 11 2.2.3 供电能力模型.......................................................................................................... 12 2.2.4 电能质量分析.......................................................................................................... 14 2.2.5 经济性综合分析算例.............................................................................................. 20 2.3 本章小结 ........................................................................................................................ 21 3 中长期电力负荷预测模型综合理论与应用...................................................................... 23 3.1 中长期电力负荷预测方法 ............................................................................................ 23 3.2 中长期电力负荷预测模型综合理论与应用 ............................................................... 24 3.2.1 灰色模型与 BP 神经网络的综合........................................................................... 24 3.2.2 组合预测的权重系数 ............................................................................................. 28 3.3 郑州新区规划区负荷预测 ........................................................................................... 34 3.4 本章小结 ....................................................................................................................... 36 4 郑州城网 20kV 应用可行性分析........................................................................................ 37 4.1 郑州城区电网现状 ........................................................................................................ 37II 4.2 郑州新区规划区采用 20kV 与 10kV 供电方案比较................................................... 39 4.2.1 郑州新区规划区负荷概况...................................................................................... 39 4.2.2 三种方案的电网规模估算...................................................................................... 39 4.2.3 三种方案的网络规模估算汇总.............................................................................. 42 4.2.4 三种方案的经济性评估.......................................................................................... 43 4.3 本章小结 ........................................................................................................................ 45 5 总结及展望.......................................................................................................................... 47 攻读硕士学位期间参加的科研实践及发表的报告..............................................................49 致谢......................................................................................................................................51