Inspection and evaluation of AC protection facilities for solid state decouplers

With the rapid development of national infrastructures, public corridors such as electricity, traffic and energy are increasing day by day, and the AC interference corrosion of buried pipelines has attracted much more attention.The solid state decoupler based drainage technology has been widely used for the AC interference protection of pipelines. However, due to the inadequate in-depth research on the solid state decoupler based drainage technology and no application standard issued in the domestic and foreign industries, no effective inspection methods and evaluation indicators could be referred by the field inspectors. Combined with many years of field inspection experience, the evaluating indicators, such as the AC interference voltage, AC drainage current, AC impedance, DC leakage current, grounding resistance, were summarized and defined, and the appropriate inspection methods and parameter requirements were put forward, which could effectively inspect and evaluate the AC drainage and DC isolation functions of the solid state decouplers. Generally, the research results can effectively guide the field inspectors to organize the drainage of solid state decouplers of the buried pipelines, which is of important guiding significance for improving the inspection and evaluation of oil and gas pipelines.