CVT铁磁谐振过电压的抑制与不同故障下二次电压特征分析  

Suppression of ferromagnetic resonance overvoltage in CVT and feature analysis of secondary voltage under different faults

作　　者：李博文 贺达 杨智 郑一鸣 蔺家骏 张乔根[1] LI Bowen;HE Da;YANG Zhi;ZHENG Yiming;LIN Jiajun;ZHANG Qiaogen(School of Electrical Engineering,Xi'an Jiaotong University,Xi'an 710049,China;State Grid Zhejiang Electric Power Co.,Ltd.Research Institute,Hangzhou 310014,China)

机构地区：[1]西安交通大学电气工程学院,西安710049 [2]国网浙江省电力有限公司电力科学研究院,杭州310014

出　　处：《浙江电力》2023年第7期38-46,共9页Zhejiang Electric Power

基　　金：国网浙江省电力有限公司科技项目(5211DS20007M)。

摘　　要：针对220 kV CVT(电容式电压互感器)因铁磁谐振故障产生的过电压问题与3U0监测装置误报警的问题,结合实际参数建立仿真模型,分析了各个参数对于过电压的影响,给出了最佳参数配置并对电路拓扑结构进行优化,有效地抑制了铁磁谐振过电压。建立仿真模型对比了各个工况下的二次电压数据。仿真结果表明:二次侧接地再恢复和一次侧合闸操作均会引发铁磁谐振,同时伴随着1/3次谐波的产生,但前者引发的铁磁谐振较为严重;采用速饱和阻尼器对铁磁谐振进行抑制,阻尼电阻为5Ω时有最佳的抑制效果;阻尼器两端并联定值电阻可以有效提高抑制效果,且当电阻阻值为5Ω时效果最佳;3U_0在不同工况下对应不同的频谱特征,可据此区分不同故障。Aiming at the problem of overvoltage caused by ferromagnetic resonance fault of 220 kV CVT(capacitive voltage transformer)and the problem of false alarm of 3U0 monitoring device,a simulation model is established based on actual parameters,and the influence of each parameter on overvoltage is analyzed.The optimal parameter configuration is given and the circuit topology is optimized,thus effectively suppressing the ferromagnetic resonance overvoltage.The simulation models are established and the secondary voltage data under various working conditions are compared.The simulation results show that both the secondary side grounding recovery and the primary side clos⁃ing will cause the ferromagnetic resonance,accompanied by the generation of 1/3 harmonics,but the ferromagnetic resonance caused by the former is more serious.The ferromagnetic resonance is suppressed by the speed saturation damper,and the best suppression effect is obtained when the damping resistance is 5Ω.The parallel fixed resis⁃tances at both ends of the damper can effectively improve the suppression effect,and the effect is the best when the resistance is 5Ω.3U0 corresponds to different spectrum characteristics under different working conditions,which can distinguish different faults.

关 键 词：电容式电压互感器 铁磁谐振 阻尼电阻 开口三角电压 隔离开关合闸 

分 类 号：TM451.2[电气工程—电器]