500kV串联补偿装置MOV运行工况及暂态负荷应力分布研究  

Research on Operation Conditions and Transient Load Distribution of 500 kV Series Compensation MOV

作　　者：矫立新[1] 郭洁[2] 列剑平 刘赫[1] 刘俊博[1] 

机构地区：[1]国网吉林省电力有限公司电力科学研究院,长春130021 [2]西安交通大学电气工程学院,西安710049

出　　处：《电瓷避雷器》2017年第3期71-76,共6页Insulators and Surge Arresters

摘　　要：金属氧化物限压器(MOV)作为输电线路串联补偿装置的重要组成部分,限制系统故障时电容器极间的暂态过电压。MOV通常由多个单元并联构成,故障瞬间会通过大电流、吸收高能量。MOV单元间暂态负荷应力的分布状况直接影响MOV的保护特性,应通过优化设计确保其暂态运行可靠性。以某500 kV交流超高压带串补装置的系统为例建立了数值仿真模型,利用EMTP-ATP研究了串联补偿装置在不同运行方式下区外故障和区内故障时MOV的负荷应力。综合MOV的电压-温度特性试验结果,深入研究了MOV并联单元间暂态负荷应力分布特性及其影响因素。研究结果表明,在暂态过程中由于电阻片阻抗的负温度系数特性导致MOV并联单元间的电流分流不均匀程度加剧,使各单元的吸收能量极不均衡,若参数控制不当会导致MOV局部单元负荷应力恶性发展直至损坏。通过研究,获得了MOV单元间暂态能量应力不均匀度与静态固有不均匀度间的关系,为优化MOV多柱单元间参数配置提供了依据。As an important part of series compensation device, the Metal-Oxide Varistors （MOV） are applied to protect the series compensation capacitors from overvoltage damage. One MOV group has multiple units to absorb a huge amount of energy when a fault occurs in series compensation system. The operation reliability of series compensation is directly determined by transient load distribution of 500 kV series compensation MOV. The reasonable design is urgently needed to insure the excellent transient thermal reliability of series compensation. This paper studies external fault and regional fault of series compensation system under different operation conditions by building simulation models of one 500 kV series compensation systems using EMTP-ATP. According to the test results and typical fault conditions, study of transient load distribution among multiple MOV units and its influencing factors has been done. The results show that the current distribution of parallel MOV units will be more uniform because of the negative temperature coefficient, and the absorption of energy will be extremely imbalance to damage the MOV units. The author studies the relationship between transient and static ununiformity of energy to provide evidence for optimize the parameter configuration of MOV.

关 键 词：串联补偿 MOV 温度系数 暂态负荷应力分布 

分 类 号：TM75[电气工程—电力系统及自动化] TM761.12