Abstract:  With the rapid expansion of electrical power network, the existing “three lines of defense” strategy has been unable to meet the requirement of the complex power system security and stable operation. A new generation of large electric power integrated defense system is urgently necessary. Furthermore, It is required to build a high-speed, real-time, safe and reliable electric power communication network to support the system protection function, such as AC/DC control, pumped storage control, accurate load shedding, panoramic perception, etc. Based on the current situation of power communication network, firstly this paper analyses the business requirement of system protection including site distribution and information flow, transmission distance, channel bandwidth, and communication time delay. Secondly, this paper compares varies communication techniques and chooses two appropriate technologies to fulfill the system protection requirement. Finally, this paper carries out a test verification on time delay of two technology schemes, which provides a theoretical and practical reference for the construction of system protection communication network.

Key words:  system protection, communication requirement, communication technology, test verification