Application Research On The Technology Of Clock Synchronization In Digital Substation Based On IEEE1588

With the integrated and network trends of substation automation systems, the clock synchronization system of digital substation are required a higher precision and a united structure. A unified, high-precision clock synchronization system based on ethernet network is the direction of digital substation clock synchronization technology.The paper compares the current clock synchronization technologies already used in substation automation system, analysis the characteristics of these technologies, and points out their existent disadvantages when implemented in digital substation. The networking trend of substation synchronization system is indicated after these analysis.The principle of IEEE 1588 synchronization protocol is introduced in this paper firstly.With the comparison with NTP(another synchronization protocol based on Ethernet-network),the advantages of IEEE1588 are listed. Combining with the structure of digital substation communication network and precision and functions requirements by IEC61850 standard, the paper proposes the application principles of IEEE 1588 protocol in digital substation and the specific implementation schemes.With the researches for the courses of the delay produced in the course of implementation of IEEE1588, this paper presents a strategy for time-stamping the synchronization messages in Mâ…¡layer.,After a analysis of effect on the clock precision caused by frequency drift of the oscillator, this paper gives the frequency compensation algorithm and implementation scheme bassed on FPGA for local clock. Finally a model is build using QuartusII, and the frequency compensation method for oscillator is timing emulated. The simulation results proved the feasibility of frequency compensation method.