The Research Of Gap Unit’s Intelligent Terminal In Taction Substations

Traction substation digitalization is the basis of upgrading the current traction power supply system and the essential way of realizing the intelligence of traction power supply system. As for this, adding intelligent terminals in process level is one of the feasible solutions. The intelligent terminal, which transfers information through wire instead of fiber within the substation, can reduce the wire laying and thus simplify the connection and facilitate maintenance. Meanwhile, the anti-interference capability of secondary equipment is enhanced and integrated management of substation automation can be easier owing to the fact that intelligent terminal itself can measure the switch location and electrical measurements.Firstly, the main functions of the intelligent terminal are concluded according to the established equipment specifications and then information model in appliance with relevant functions of the intelligent terminal is built based on the IED layered model structure provided by IEC 61850 standard. On this basis, the IED capability description file is configured with IED configuration tools.Secondly, to realize the core functions of the intelligent terminal in bay level unit, the intelligent terminal hardware scheme is designed. Four pieces of circuit boards are classified by their function difference, that is, CPU board, AI board, I/O board and power source board with ADSP-BF609 as the CPU. Besides, the four circuit boards are connected together onto the backboard, which is mainly used for the transmission of electrical information and power source distribution of different voltage classes, to ensure external ports are set on the same side.Finally, the program design is discussed based on the hardware circuit in this paper, which can realize the core functions of the intelligent terminals in the bay level unit of the substation, such as AI, DI, and DO. Furthermore, the cubic Hermite piecewise interpolation is adopted to meet the requirements of synchronized sampling and accurate time interval between two messages is realized by means of dual-core configuration of ADSP-BF609. The testing outline of the traction substation bay level unit’s intelligent terminal is designed, followed by the conduction of the test, through which the device is verified to be capable of completing the key functions of the intelligent terminals provided by relevant rules.