江苏省软件专项《主动配电网协调控制与能量管理关键技术研发与产业化》 编号：2017880 国家集聚计划《主动配电网协同控制关键技术及装备》 编号：2015359
State Grid Jiangsu Electric Power Company, LTD. State grid Suqian power supply company
与电磁式电压互感器相比，电力系统中常用的电容式电压互感器存在诸如耐冲击电压强度高、造价较低以及维护成本及工作量小等优点，但仍存在一些常见问题，例如所占空间大，所需绝缘设计水平高（与高压直接接触），恶劣环境下绝缘失效等问题。针对这些问题，本文设计了一种适用于10 kV及以下电压等级的非接触式耦合型电压互感器。首先基于电磁感应原理，利用电压互感器侧量端与电缆内芯、输电线路、绝缘套管内部引出引入线等形成的耦合电容充当高压端电容，利用电压互感器侧量端与大地间形成的电容充当低压端电容。之后理论分析了电压互感器电容对频率特性的影响，通过有限元仿真计算并优化了耦合式电压互感器测量端与高压输电线之间的电场和电容。最后在单相10 kV电压等级下输电电缆上进行了试验，结果表明所设计的互感器可以准确、实时的测量电压，能够为建立智能电力系统，电网实时在线监测，继电保护现场运行提供新的方法和思路。
Compared with electromagnetic voltage transformer, capacitor voltage transformer commonly used in power system has many advantages, such as high shock resistance, low cost, low maintenance and workload cost, but there are still some common problems: the space occupied is large, the required insulation design level is high (directly in contact with high voltage), and insulation is easily failure in bad environment. In order to solve these problems, a non-contact capacitor-coupling voltage transformer suitable for 10 kV and below is designed. Based on the principle of electromagnetic induction, the coupling capacitance formed by the measuring end of voltage transformer and the inner core of cable, the transmission line or the wire inside the insulation sleeve are used as the high-voltage terminal capacitance, and the capacitance formed between the voltage transformer measuring end and the earth is used as the low-voltage terminal capacitance. Then the influence of voltage transformer capacitance on frequency characteristics is analyzed theoretically. The electric field and capacitance between the measurement end of coupling voltage transformer and high voltage transmission line is calculated and optimized by finite element simulation. Finally, the test is carried out on a single-phase 10 kV transmission cable. The results show that the designed transformer is capable of measuring the voltage accurately in real time, providing new methods and ideas for the establishment of intelligent power system, real-time online monitoring of power grid and field operation of relay protection.