Application of solid state-decoupler in AC interference mitigation of pipelines

Currently, there are a lot of technical gaps and misunderstandings on the type selection, application design and detection of solid-state decouplers in the pipeline industry. Development of relevant technical standards is seriously lagged behind the engineering application. In this paper, the internal structures and components of solid-state decoupler were analyzed, and then the technical specifications (e.g. DC leakage, AC impendence and Fail-safe) were discussed on the basis of field inspection data. Resolutions were proposed correspondingly to the inappropriate design and application of the fault current protection and the electromagnetic induction interference mitigation of buried steel pipelines. The influences on external inspection of pipelines with solid-state decoupler used for AC interference mitigation were identified. The solid-state decoupler may be misused in the AC interference mitigation, which not only induces higher engineering investment, but also brings negative impacts on corrosion prevention of pipelines. Therefore, it is necessary to launch relevant technical standards and specifications as soon as possible to guide the application of this product rationally.