| 基于回路阻抗模型的城乡低压配电网络运行状态评估 |
| |
| 引用本文： | 殷自力,张伟.基于回路阻抗模型的城乡低压配电网络运行状态评估[J].农业工程学报,2018,34(22):162-168. |
| |
| 作者姓名： | 殷自力 张伟 |
| |
| 作者单位： | 1. 国网福建省电力有限公司，福州 350003;,2. 积成电子股份有限公司，济南 250100; |
| |
| 基金项目： | 国家自然科学基金委青年基金项目(61403321) |
| |
| 摘 要： | 为解决城乡低压配电网运行状态评估问题,提出了一种基于智能电表的城乡低压配电网运行状态评估方法。建立了低压配电网回路阻抗模型,提出了基于智能电表电压与电流变化速率的回路阻抗近似计算方法;建立了需求侧实时电压数据阵和需求侧实时电流数据阵分别记录配电变压器所属的所有智能电表不同时刻的电压与电流量测信息,并通过两矩阵生成了需求侧实时回路阻抗数据阵,以记录配电变压器所属的所有智能电表上游回路的阻抗变化情况;最后基于回路阻抗数据阵详细讨论了低压配电网运行状态的评估方法。实例分析验证了该文所提方法的可行性,智能电表低压回路阻抗的近似计算值与实际值的最大误差不超过81%,最小误差不超过11%,平均误差不超过22%,可满足现场工程实际需求。
|
| 关 键 词： | 电表 模型 低压配电网 回路阻抗 状态评估 |
| 收稿时间： | 2018/5/8 0:00:00 |
| 修稿时间： | 2018/10/16 0:00:00 |
Evaluation for urban and rural low-voltage distribution operation state based on loop resistance model |
| |
| Yin Zili and Zhang Wei.Evaluation for urban and rural low-voltage distribution operation state based on loop resistance model[J].Transactions of the Chinese Society of Agricultural Engineering,2018,34(22):162-168. |
| |
| Authors: | Yin Zili and Zhang Wei |
| |
| Institution: | 1. State Grid Fujian Electric Power Company, Fuzhou 350003, China; and 2. Jicheng Electrocics Corporation, Jinan 250100, China; |
| |
| Abstract: | The operation state assessment can evaluate and analyze the real-time and historical operation state of the power grid, and predict the future power grid operation situation, screen the weak link of the power grid, and eliminate the power grid stealth fault in the bud, which is one of the important means to improve the power supply reliability of the power grid. In current urban and rural low-voltage distribution network, due to the lack of graphics and model data, small measurement configuration and poor data quality, it is of great practical significance to use the widely configured low-voltage user smart meter as far as possible to realize the operation state evaluation of the low-voltage distribution network. Each smart meter forms a loop through the live line, neutral line, T-connected line, load and distribution transformer. The impedance of the load varies according to the quantity and power of the electrical equipment. However, the loop resistance formed by the live line, the neutral line, the T-connected line, and the distribution transformer in the upstream of the smart meter does not change in a short time. If the loop resistance is abrupt, it indicates that the operating state of the loop is abnormal. According to this principle, the operating state of the low-voltage distribution network can be evaluated. When the voltage value of the equivalent power supply in the upper main network of the distribution transformer is almost invariable or cannot be collected, the loop resistance can be approximately determined by the change rate of the voltage and current measured by the smart meter. The demand side real-time voltage data matrix is set up to record the real-time voltage measurement information collected by the smart meters on the low-voltage demand side of a distribution transformer. The demand side real-time current data matrix is set up to record the real-time current measurement information collected by the smart meters on the low-voltage demand side of a distribution transformer. The demand side real-time loop resistance data matrix is set up to record the real-time loop resistance information of all low-voltage demand side smart meters on the distribution transformer. The method of generating the demand side real-time loop resistance data matrix from the demand side real-time voltage data matrix and the demand side real-time current data matrix are discussed in detail. Finally, the evaluation method of the operating state of the low-voltage distribution network is discussed in detail based on the loop resistance data matrix. Many cases such as line broken line, line fault blackout, line plan blackout, load unstarted, user uninhabited, electricity stealing, smart meter damage, line aging alarm and line aging fault were analyzed in detail. The feasibility of the proposed method was analyzed by taking a low-voltage distribution network with four smart meters as an example. The maximum error of the approximate value and the actual value of the low-voltage loop resistance of each smart meter was not more than 81%, the minimum error was not more than 11%, and the average error was not more than 22%. The error was far less than the set line aging alarm limit LA and line aging fault limit LB. Therefore, in the actual calculation, when the power supply voltage of the main network upstream of the distribution transformer is not changed or cannot be obtained, the approximate value of the loop resistance can be used to express the change trend of the upstream loop resistance of the smart meter. The method proposed in this paper can meet the actual needs of field engineering. |
| |
| Keywords: | ammeter models low-voltage distribution network loop resistance state evaluation |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《农业工程学报》浏览原始摘要信息 |
| 点击此处可从《农业工程学报》下载免费的PDF全文 |
|
