接地消弧装置导致PT铁磁谐振机理分析  

Mechanism analysis of PT ferroresonance caused by grounding-type arc-extinguishing device

作　　者：杨文勇 刘丽 戴宇 李军 王俊 古展基 YANG Wenyong;LIU Li;DAI Yu;LI Jun;WANG Jun;GU Zhanji(Bijie Power Supply Corporation of Guizhou Power Grid Co.,Ltd.,Bijie 551700 Guizhou,China;Guangzhou Smart Energy Technology Co.,Ltd.,Guangzhou 510530 Guangdong,China)

机构地区：[1]贵州电网有限责任公司毕节供电局,贵州毕节551700 [2]广州穗华能源科技有限公司,广东广州510530

出　　处：《电力大数据》2019年第8期88-92,共5页Power Systems and Big Data

摘　　要：在配置有接地消弧装置的中性点不接地配电系统中,消弧装置动作过程能够导致线路电压骤变,从而可能引起电磁式电压互感器(PT)产生铁磁谐振,对设备和系统造成重大危害。为了避免铁磁谐振影响,需要对接地消弧装置产生谐振的机理进行研究。通过分析中性点不接地配电系统结构,并结合接地消弧装置动作过程,研究了接地消弧装置动作对配电系统运行参数的影响。研究了PT铁磁谐振原理,并结合接地消弧装置动作特性对消弧装置导致PT铁磁谐振的机理进行了理论分析。提出了一种基于谐振回路特性和铁芯励磁特性的能够表达谐振非线性过程的迭代计算方法,通过MATLAB对铁磁谐振进行了仿真。结果说表明接地消弧装置能够导致PT铁磁谐振,谐振的类型受线路对地电容大小的影响,大多数情况下产生的是分频谐振。In neutral point ungrounded distribution system that equipped with grounding-type arc-extinguishing device,the action of grounding-type arc-extinguishing device may lead to abrupt voltage change of distribution line and cause potential transformer(PT)ferroresonance,which will make harm to the equipment and the system.In order to avoid the influence of PT ferroresonance,the mechanism of PT ferroresonance caused by grounding-type arc-extinguishing device needs to be studied.The influence on distribution network operation parameters caused by the action of grounding-type arc-extinguishing device is studied by analyzing the structure of neutral point ungrounded distribution system and the sequence of action of grounding-type arc-extinguishing device.The mechanism of PT ferroresonance caused by grounding-type arc-extinguishing device is theoretically analyzed by studying PT ferroresonance theory and the action characteristics of rounding-type arc-extinguishing device.An iterative computing method base on the excitation characteristics of iron core and the characteristics of ferroresonance circuit that can represent the non-linear process of resonance is proposed.Simulation of PT ferroresonance is made on MATLAB and the results show that grounding-type arc-extinguishing device can lead to PT ferroresonance and the type of ferroresonance is influenced by the grounding capacitance and subharmonic ferroresonance happens in most cases.

关 键 词：接地消弧装置 电磁式电压互感器 铁磁谐振 中性点不接地系统 励磁特性 

分 类 号：TM45[电气工程—电器]