The Development about Multifunction Merging Unit Used in Smart Substation

The merging unit is used to realize the digitalization and sharing of the data of process and is widely used with the electronic voltage transformer (EVT) and electronic current transformer (ECT). As the construction of smart substation which is presented by the state grid company of china, a serial new requirements and needs about the merging unit are proposed and the merging unit which only sends the sampling value can not meet it. The new demands of the smart substation are analyzed, The design of hardware and the implement of the function are presented. The multifunction which including the model of sampling, the data catenation, the acquisition of status signal through GOOSE , the voltage parallel and switching and the synchronization of device are analyzed in detailed. At the end, the function of intelligent diagnosis and debug is introduced. The device has been used in the project of smart substation and takes good effect.