Research On Intelligent Substation In Information Flow Modeling And Secondary System Simulation

A Cyber-physical power system(CPPS)is a complex multi-dimensional system that couples network computing and physical environment.Its information systems play an important role in the safe,stable,and reliable operation of power systems.The intelligent substations are the key nodes of the CPPS,where the information flows control the energy flows,and the energy flows react and feed back the information flows.A digitalized and networked environment is essential for the intelligent substations to complete information gathering and decision-making.Therefore,research on intelligent substations should focus more on the secondary systems.This paper focuses on the information flows of intelligent substations,and uses mathematical modeling and simulation methods to deeply explore the performance of intelligent substation secondary system based on communication network architecture.This paper first models the information flow of the intelligent substation,including the modeling of the packet transmission paths from sources to destinations and the maximum end-to-end transmission delay of the packets.Based on data exchange mechanism of the intelligent substation communication network,the expression form of the packet transmission path is figure out.Additionally,network calculus theory is used to find out the maximum end-to-end transmission delay of the packet.It is beneficial to study the effectiveness of protection and control functions of intelligent substation.Then,based on the IEC 61850 standard,the functions of the intelligent electronic devices(IEDs)in the intelligent substation secondary system are analyzed and discussed in detail.With network simulation software OPNET,the main communication devices of the intelligent substation secondary system are modeled,and the model functions are customized according to the needs,which form various functional modules and lay the foundation for the simulation of intelligent substation secondary system.Finally,an integration scheme of the intelligent substation secondary system is studied.The established simulation platform is used to model the intelligent substation secondary systems,in order to analyze and verify the relay protection function of the secondary system,and to compare the end-to-end delay of packet transmission obtained by simulation with the maximun end-to-end delay of packet transmission obtained by theoretical calculation.