某变电站直流电源阀控式铅酸蓄电池失效分析

Failure Analysis of Valve regulated Lead acid Battery of DC Power Supply in A Substation

摘要:

对某110 kV变电站直流电源故障蓄电池组铅酸蓄电池开展了失效分析。拆解试验结果表明，该站直流电源蓄电池失效主要是由正极板栅腐蚀断裂与负极汇流排腐蚀断裂所致。正极板栅腐蚀断裂与蓄电池浮充电压过高有关。负极汇流排腐蚀与其材质和工艺密切相关，该负极汇流排采用Pb-Sn-Sb合金配方，会引起Sb、Sn在合金晶界处偏析，加速负极汇流排的晶间腐蚀。最后，根据存在的问题，提出了改进措施，避免以后类似故障发生。

Abstract:

The failure analysis of lead acid battery of DC power supply in a 110 kV substation is carried out. The results of dismantling test show that the failure of DC power supply battery in this station is mainly caused by the corrosion fracture of positive plate grid and negative bus bar. The corrosion and fracture of positive plate grid is related to high floating charging voltage of the battery. The corrosion of negative bus bar is closely related to its material and process. The negative bus bar uses Pb Sn Sb alloy, which will cause Sb and Sn segregation at the alloy grain boundary, and poor welding process could accelerate the intergranulary corrosion of negative bus bar. Finally, according to the existed problems, the improvement measures are put forward to avoid similar failures in the future.