Method Research On Virtual Simulation Of Secondary System And Its Implementation In Smart Substation

With the development of the smart grid,smart substations are also in a wide range of construction and application.Compared with the traditional one,smart substation has many new secondary devices and the information is digital,which transmitted through communication network.For professional technicians or engineers,the protections'principles are invisible,the information transmission from process level intelligent devices including merging units,intelligent terminals to protection or measuring&control devices also becoming transparent.Besides,Electric signal is no longer transmitted through traditional cable wiring,but through "virtual terminal"connections that based on the standard data model and communication message.Therefore,how to make the technicians or engineers have a deep study on the devices and circuits of the secondary system draws our attention.At the same time,the research on the secondary system's whole simulation and testing of smart substation still lacks,most of which focuses on the function testing of single device and pays little attention to the closed loop testing in logic of the entire system.Therefore,there is still is a lot work to do in order to meet the requirement of the technicians and engineers in smart substation.According to the situation and the future of the domestic smart substation,this paper proposes a virtual simulation and implement way of smart substation secondary system for the engineers' training.It simulates the intelligent protection device in smart substation,implements its functions by programming,and displays the protection operating characteristics and logic characteristics visually.Meanwhile,this paper establishs the virtual protection device's data model based on IEC 61850 standards,semantically defines its function and message and configures its dataset.Based on RTDS(Real Time Digital Simulator)platform,it builds up the primary system model as the simulation data source;also uses the GTNET_SV and GTNET_GSE module to construct merging unit and intelligent terminal models.By researching on the communication of Sampled Values and GOOSE,this paper analyzes and establishes the system's communication mode.Through connecting the virtual protection to RTDS system and configuring the communication parameters,we can take a closed loop testing.By testing,we can test the basic functions and responding characteristics of the virtual protection device,know of the message and logic flow in the internal logic modules in protection device.Besides,the system has a secondary circuit show&analysis module that can display the virtual secondary circuit's connection in multi-dimension by visual technology.The virtual simulation system for smart substation secondary system can help the trainees have a deep understanding of the intelligent electric devices' working principles;learn the logic coordination among multiple logic components in protection device in case of fault;analyze the protection acting report.By connecting the virtual protection device to RTDS and testing,systematically understand the working logic and message flow of secondary circuit in smart substation.Aiming at the practical engineering training,it is not very easy to configuring much equipment.Through software,we can simulate a variety of virtual devices and cut down the physical ones,which is much more economical.