基于失重方法的雷电对接地装置腐蚀的影响研究

Influence of Lightning on Grounding Device Corrosion Based on Weightlessness Method

雷电发生时,接地装置每年都会有不同程度的腐蚀,使建筑物和设备接地电阻阻值发生变化,从而存在安全隐患。一旦遭受雷击,强电流入地时产生较高的残压,影响到附近人身和设备的安全运行。为切实了解接地网遭受雷电流冲击情况,掌握接地装置易损点的数据,构建了2个试验模型,分别采用雷电冲击试验和工频电流试验的数据进行对比分析。根据理论研究和试验数据,研究了接地装置在雷电冲击下和工频电流下平均腐蚀速度随时间的变化关系,发现雷电流和工频电流均会通过电解作用来促进接地装置的腐蚀,并且工频电流由于具有持续时间长、残存电荷量大的特点而对接地装置的腐蚀作用更大。

The grounding device is corroded to varying degrees every year when lightning occurs.The corrosion changes the grounding resistance value of buildings and devices,resulting in potential safety hazards.Once struck by lightning,high residual voltage is generated when strong electricity flows to the ground,affecting the safety of people and equipment nearby.In order to understand the impact of lightning current on grounding network and grasp the data of vulnerable point of grounding device,two test models are constructed,and the data of lightning impact test and power frequency current test are used for comparative analysis respectively.According to the theoretical research and experimental data,the relationship between average corrosion velocity and time of grounding device under lightning and power current is studied.It is found that lightning current and power frequency current will promote corrosion of grounding device by electrolysis.Moreover,the corrosion effect of power current on grounding device is greater due to its long duration and large residual charge.