摘要本篇论文针对6～35KV配电网发生单相接地短路时电容电流产生的影响，于此基础上介绍分析了电容电流产生与测量。本篇论文在针对传统电容电流检测缺点基础上，巧妙给出一个可以规避传统检测方式缺点的新式检测方式—单频率测量法,单频率测量法通过对两个测量数据的比对来得出电网电容和电容电流数值即比对从电压互感器开口三角侧输进的恒定电流信号、电压互感器信号输入侧电压和二次星形侧相电压的电压信号。因为传统测量方法无法解决电压互感器短路阻抗和注入信号频率选取组合对测量结果的影响，所以针对这一问题，通过对单频率测量法的理论研究和实际验证，它完全避免上述问题，而且该方法不会导致配电网的不正常运行。40943
本论文通过对传统电容电流测量方法的研究，找到了能够精确检测电容电流的有效方法--单频率测量法，保证了电力系统安全稳定运行。
毕业论文关键词:配电网 中性点不接地 电容电流 电压互感器 单频率测量法
Abstract
This paper proposed a measurement method based on capacitive current，introduce how to produce for capacitive current and the disadvantage for one-phase grounding capacitive current. Based on the disadvantage of summarizing traditional capacitive current. A novel method of capacitive current measurement (injecting one frequency signal measurement) is proposed for insulated neutral distribution networks. With a constant current signal injected into the open-delta side of the voltage transformer, the voltage of the open-delta side and the phase voltage of the secondary star side are measured. The distribution network capacitance and capacitive current to ground can be calculated in accordance with the injected current signal and themeasured voltage signals. The proposed method avoids the influence of short-circuit impedance of the voltage transformer and the injecting signal frequencies. The results of dynamic power system simulation show that the proposed method is with high precision, and can be used in real-time without power supply interrupting.
Through studying on the measurement of capacitance current and the system design, find the way of the precision measurement of capacitance current---injecting one frequency signal measurement. Choose the means because of capacitance current and the condition of system, in order to ensure the safety of the equipment and reduce the loss of electric power.
Key words:distribution networks insulated neutral distribution networks capacitive current voltage transformer injecting one frequency signal measure
目 录
摘要Ⅰ
Abstract Ⅱ
1 绪论 1
1.1 研究的背景和意义 1
1.3 本文所做的工作 2
1.3.3 研究目标 2
1.3.2 研究内容 2
1.3.3 研究方案 2
1.4 小结 3
2 中性点不接地系统电容电流概述 4
2.1 正常状态下的运行特点 4
2.2 单相接地电容电流 6
2.2.1 产生的原因及其危害 6
2.2.2 发生单相接地短路故障时电容电路的计算 7
2.3 小结 8
3 不接地系统电容电流的传统检测方法 9
3.1 估算法 9
3.1.1 电缆线路电容电流的估算 9
3.1.2 架空电路电容电流的估算 10
3.2 直接法 11
3.2.1 使用消弧线圈补偿接地 11
3.2.2 不使用消弧线圈补偿接地 11 中性点不接地系统电容电流检测方法及系统设计:http://www.751com.cn/zidonghua/lunwen_40814.html