The Research And Hardware Development Of Merging Unit In35KV Smart Substation

Smart substation based on IEC61850realizes information acquisition of processlayer in a digital and sharing way which improves the reliability of informationtransmission. The core component is merging unit, as the data interface betweennon-conventional transformer or conventional transformer and secondary protectionand control devices, of which the operating reliability and accuracy directlydetermines the operating characteristics of substation protection system and alsoaffect t security and stability of the entire grid.For the above problems, the design of Merging Unit which is suitable to the35kVsubstation is studied in this paper. Based on the FPGA chip and the ARM chip, a highaccuracy Merging Unit is realized which successfully accomplishes thecommunication between the transformers and the protection devices.The main contributions of this thesis are as follows:1Based on the analysis of the research status of Merging Unit at home andabroad, based on the international standard protocol of IEC60044-8and IEC61850-9,this thesis proposes the designing scheme of Merging Unit which considers thesatisfactory interface between instrument and secondary protective device.2Based on FPGA (EP1C3T144) chip and ARM (STM32F103ZET) chip, thisthesis designs the Merging Unit hardware platform which satisfies the stands, it meetsthe functional requirements of35kV substation.3Based on the platform mentioned above, this thesis completes the functionaltest of time synchronization, data acquiring and package sending. It realizes thetransmission of Merging Unit synchronizing information, solves the problems ofinterface between instrument and secondary protective device.Merging unit as the core component of the digital substation, takes the importanttask of the data transmission, so it is very important to design the merging unit.