There are three main ways to synchronize the time with the GPS clock synchronizer in the control system: serial port time synchronization, hour/minute/second pulse time synchronization, IRIG-B format code time synchronization.
(1) The serial port time is synchronized. The synchronous clock equipment obtains the standard satellite time and outputs the time information in the form of serial data stream. Various automatic devices receive the serial time information once per second to obtain time synchronization. The serial port is divided into RS232 interface and RS422 interface mode. .
(2) Pulse timing. General GPS receivers will provide 1PPS second pulse signal. 1PPS is a pulse signal corresponding to the whole second, and its time deviation is <1μs, which is very suitable for the synchronization of various devices. Through the second pulse receiving, amplifying and multiplexing equipment, multiple channels of second pulse are simultaneously introduced into the second pulse receiving input terminals of all the measurement and control devices in the station.
(3) IRIG-B mode time synchronization: IRIG-B code is a clock code specially formulated for clock transmission. Output one frame of time information in the order of second, minute, hour, and date every second.
Through the above methods, the GPS clock synchronization system can transmit time information to the automation devices, microcomputer protection devices, fault recorders, and computer monitoring systems in the substation.
