平原型风电机组用箱变雷击损坏探讨

Discussion on the Lightning Damage of Box-type Substation for Plain Wind Turbine Applications

某平原风力发电机组,输电线路发生雷电过电压,造成箱变内高压侧闪络,高压熔断器熔断。对此进行深入分析,首先对现场进行了调查,检查了架空输电线、一次回路、跌落保险、干变主体,测量了绝缘电阻、绕组的直流电阻、箱变接地电阻、杆塔接地电阻;其次对故障现象进行原因分析,解析了变压器损坏的机理、雷电过电压的防护、避雷器保护作用、变压器闪络和电弧短路等关键性技术问题;然后对故障处理进行分析,对现场快速修复的条件、主要步骤进行了讨论;最后对故障进行综合分析,提出相应的改进措施,为后期同类型风电场类似事件处理提供参考。

In some plain wind turbine system,lightning strikes on its overhead transmission line,and flashover occurs at the high voltage side of its box-type substation,the high voltage fuse is blown.An in-depth analysis of the fault was made.Firstly,a field investigation was conducted including overhead transmission lines,primary circuit,drop type fuse,dry-type transformer,and some measurements were conducted such as insulation resistance,winding D.C.resistance,the grounding resistance of box-type substation,the grounding resistance of power line poles.Secondly,analysis of the fault cause was conducted,the mechanism of transformer damage was analyzed.Some key technical problems such as lightning overvoltage protection,lightning arrester protection,transformer flashover and arc short circuit were analyzed also.Moreover,fault treatment analysis was conducted.Conditions for filed rapid repair and main steps were discussed.At last,fault synthetic analysis was conducted and the prevent measures were presented.It provides reference for similar events of the same type of wind farm in the later stage.