A Study And Implement Of Network Time Synchronization System Under Power System Environment

With the development of large area interconnected power system and the UHV transmission technology, network time synchronization is applied widely. At the same time, the real-time performance of system is strictly required. The key of ensuring real-time performance of system is keeping the time synchronization among equipments in the power system network. In response to this demand, a strictly time synchronization system is designed in the thesis, in which network time synchronization based on the NTP(Network.Time Protocol) was implemented.Firstly, the pros and cons of several existing clock synchronization methods are compared, and the NTP protocol is used as system time synchronization due to its existing network. Secondly, the domestic and abroad research of high precision NTP protocol is reviewed, and the synchronization principles and the key of algorithms of NTP protocol are elaborated. Thirdly, considering the features of the secondary side power system (protection or control side of the side), a system hardware design method which use a samsung s3c2410 chip as a core is proposed. The idea of the core board plus the bottom board is adopted in this hardware design method. The core board includes the main controller, the external storage circuit and the power supply circuit; the bottom board includes the power, serial communication, and ethernet interface modules. On the premise to guarantee the accuracy of system clock, Linux is chosen as the real-time operating system, completed the Linux transplant and the development of the ethernet adapter driver.Thirdly, in the software design part, we mainly research the implementation of the network time synchronization. The whole design is based on the idea of construction of modules, including the accept of the satellite information modules, the realization of NTP server and client modules, the network monitoring modules, inquiry of wrong statement of the satellite modules and the LCD display modules.1) The accept of the satellite information modules received from the serial part to rough synchronization the local clock.2) The client and server mainly use the synchronized system time and calls the NTP program on the Linux OS to realize the clock system in the network layer.3) It is convenient to design the network monitoring modules, inquiry of wrong statement of the satellite modules and the LCD display modules for the usage of users and the debugging of the designers. Finally, the synchronization performance of the NTP system is tested through simulating environment in lab. The experimental results show that the synchronization precision is 10 milliseconds, which meets the requirement of network time synchronization system in secondary side power system, and there would be a brighter value by applying it into practice.