35kV中性点经消弧线圈接地系统几种铁磁谐振消谐措施有效性分析  

The Effectiveness Analysis of Ferroresonance Suppression Measures for 35kV Neutral Point Through Arc Suppression Coil Grounded System

作　　者：王鹏[1] 郭洁[1] 齐兴顺 杨积成 张鹏娇[3] 

机构地区：[1]西安交通大学电气学院,西安710049 [2]庆阳供电公司,甘肃庆阳745000 [3]西北电力设计院,西安710075

出　　处：《电瓷避雷器》2010年第6期34-37,共4页Insulators and Surge Arresters

摘　　要：由于电磁式电压互感器(PT)饱和引起的铁磁谐振严重影响整个系统的安全运行。以某35 kV中性点经消弧线圈接地系统为例建立仿真模型,对PT高压侧中性点经PT接地(4PT)、非线性电阻消谐器接地,PT开口三角绕组接入阻尼电阻,系统母线加装星形避雷器四种目前常用消谐措施进行了仿真计算和分析比较,计算结果表明:对于中性点经消弧线圈接地系统中常见的由于单相接地故障消失引发的分频铁磁谐振,4PT法和PT高压侧中性点经非线性电阻消谐器接地抑制谐振效果不明显,由于系统发生谐振时避雷器没有动作,母线加装星形避雷器对谐振的影响很小,而PT开口三角接入阻尼电阻对谐振具有较好的抑制作用,并且电阻越小抑制效果越明显,但是小电阻的热容量太大,容易引起电阻烧坏,且电阻热容量越大成本越高,应尽量使阻尼电阻短时间接入。Ferroresonance due to the saturation of PT has a serious impact on the safety operation of the whole system. A 35 kV neutral point through arc suppression coil grounded system models is established as a example, simulating the four common suppression measures, including： connecting single phase PT to the neutral point of PT high voltage side （4PT）, connecting nonlinear resistance to the neutral point of PT high voltage side, connecting damp resistance to the broken delta winding of PT, connecting four star type MOA to the system bus. Then detailed analysis and comparative study on above suppression measures are presented. The simulation result show that 4PT and connecting nonlinear resistance to the neutral point of PT high voltage side have little effect on subharmonic ferroresonance caused by the disanoearance of single-phase ground fault. The MOA does not action when ferroresonance happen, so connecting MOA to the system bus affect ferroresonance little, connecting damp resistance to the broken delta winding of PT can eliminate ferroresonance effectively. The suppression effect is more obvious when the resistance is smaller. In order to avoid resistance being burntout, the resistance should be connected in a short time.

关 键 词：铁磁谐振 电磁式电压互感器(PT) ATP—EMTP 消谐措施 

分 类 号：TM862[电气工程—高电压与绝缘技术]