Research on the Influence of Stray Current on Grounding Grid and Corresponding Protection

摘要

Stray current, as a special current, is common in the earth, and it will have a certain impact on the grounding grid of the power system. Based on CDEGS modeling, this paper studies the distribution of stray current and its influencing factors. In addition, the stray current in the soil not only causes corrosion to buried metals, but also affects the cathodic protection system of buried metals to varying degrees. It is proved through simulation that a certain level of stray current will have a serious impact on the sacrificial anode cathodic protection method, but the external current cathodic protection method has little effect. Therefore, it is recommended to use the external current cathodic protection method in the area of stray current interference. Combined with an engineering example in a certain area, a corresponding external current cathodic protection scheme is designed according to the analysis of the factors affecting the stray current, which greatly reduces the corrosion rate.