低压配电用SPD动作负载试验研究

依据IEC61643-1:2005中7.6.4的规定,对Ⅰ、Ⅱ级电涌保护器进行动作负载试验中的确定续流大小的预备性试验与动作负载预处理试验时的现象,通过对冲击相角、施加不同Uc值、SPD(SPD,surge protection devices)设计结构等的分析,提出①Ⅰ、Ⅱ级电涌保护器在动作负载试验中最易出现续流或者燃烧爆炸等危险现象的相角为40°～60°和220°～240°,而并不是90°和270°;②试验时施加的Uc值对试验现象起着重要作用,Uc越小试品越不易产生续流等现象,Uc越大越易产生续流等;③内部使用铜织带作为连接结构的SPD,在试验过程中,铜织带或因过长、或因高低压连接点距离太近等结构因素产生高压端铜织带被电动力打断等现象;④通过对相角和不同Uc的分析,提出了一种利用Uc的变化率(K)及K.Usinθ来对确定续流与预处理试验中最易发生续流相角进行解释。这对工程师对理解Ⅰ、Ⅱ级电涌保护器进行动作负载试验时的试验现象提供了试验和理论支持,并为SPD设计者提供了修整思路,具有一定的工程意义。

Experiment Research on Preconditioning Tests for Operating Duty Tests of SPD Used in Low-Voltage Systems

The research is based on 7.6.4 of IEC61643-1:2005,to analysis the process of figure out the range of the continuous current and the preconditioning tests for operating duty tests of Ⅰ,Ⅱ classified SPD by phase,different Uc,and the structures of SPD(SPD,surge protection devices),and it is proposed that:① the most dangerous phases where continuous current or fire explode occurred in operating duty tests of SPD are 40°～60° or 220°～240°;② the Uc value applied in test is very important to the test phenomenon,the higher Uc is,the easier the continuous current could be caused;③ copper strap is used as the connect structure inside SPD,during the test,the copper strap would be break by electric power because of the strap was to long,or the distance of the node of high voltage and the node of low voltage is too short;④it is proposed that using the K defined by the variance ratio of Uc,and K·Usinθ to determin the most dangerous phases which could cause continuous current by analysis of phases angle and different Uc.The test and theory support are provided for engineers to understand and analyze the test phenomenon in operating duty tests of SPD,the modify thinking is provided for the SPD designer,and certain engineering significance.