Distribute Coordinated Wide Area Current Differential Protection Based on IEC61850

Protection system will undergo profound evolution with the new feature coming forth with the formulation of new standard IEC 61850. Based on the flexibility come with the subscription/publish mechanism of the new standard, a new paradigm of current differential relaying are discussed in this paper. A distribute coordinated expert system (ES) has been developed to form primary/backup protection zone of a substation based on the topological information of the substation and neighboring substation that are accessible to substation host. Thereafter, subscription/publish relation and dataset of the protection system can be coordinated dynamically online. The logical nodes (LNs) that implement differential relaying function can collect their interesting measurements from dataset contain specific electronic instrument transformers and the fault can thus be detected