高压内置型高阻抗变压器涌流特性对保护的影响  

Impact of Inrush Current Characteristics of High-voltage Built-in High-impedance Transformer on Relay

作　　者：李晓华[1] 罗龙波 谢金泉[1] 李一泉[3] 李英 

机构地区：[1]华南理工大学电力学院,广东省广州市510640 [2]广州供电局有限公司,广东省广州市510630 [3]广东省电力调度中心,广东省广州市510600 [4]衡阳变压器有限公司,湖南省衡阳市421007

出　　处：《电力系统自动化》2016年第11期108-114,共7页Automation of Electric Power Systems

基　　金：国家自然科学基金资助项目(51377059);广东省自然科学基金资助项目(S2013010012885)~~

摘　　要：结合现场保护误动实例,对高压内置型高阻抗变压器励磁涌流特性进行了深入分析,结合变压器结构的特点指出其励磁涌流大且衰减缓慢的原因。进而运用PSCAD/EMTDC搭建了仿真模型,对空载合闸产生的涌流零序分量大小及衰减时间的影响因素进行了仿真研究。建议新投运高压内置型高阻抗变压器时,考虑励磁涌流衰减时间最长的极端工况,对线路零序保护Ⅳ段动作时限进行重新整定,以保证变压器正常投运。Owing to the small equivalent resistance and special internal structure, the inrush current of high-voltage built in high-impedance transformer is large and decays slowly. A malfunction of the protection occurred as the zero sequence of magnetizing inrush current is too large during a closing experiment on high-voltage built-in high-impedance transformer by a transformer substation of Guangdong. According to the recorded wave of actual spot data, the malfunction of the zero-sequence overcurrent protection and the zero-sequence protection 1V line may occur since the zero sequence of magnetizing inrush current is large and decays slowly. To solve this problem, the characteristics of magnetizing inrush current are analyzed deeply along with the structure as reasons why the inrush current of high-voltage built-in high-impedance transformer is large and decays slowly. Then the influencing factors on inrush current zero-sequence component of transformer closing are simulated by using PSCAD/EMTDC. It is proposed that when putting a new transformer into operation, the extreme condition of the longest magnetizing inrush decay time be taken into account so that the time limit of zero-sequence protection lg can be re-set to ensure the transformer normal operation.

关 键 词：高阻抗变压器 高压内置 励磁涌流 和应涌流 零序过流保护 线路零序保护 

分 类 号：TM774[电气工程—电力系统及自动化]