Research and Realization of the High Accuracy GPS Synchronization Clock

This paper presents a new method of implementing the highly accurate clock by the synchronization of crystal oscillator clock with the GPS clock, which is based on the complementation of the accuracy of the GPS and crystal oscillator. The method accurately measures the actual frequency of the crystal oscillator clock by the one pulse per second of GPS, then corrects the crystal oscillator clock on-line and corrects the absolute timestamp by the IRIG-B code. The synchronous timer can keep its precision at 0.1 μs and is not affected by the possible transient invalidation of GPS. The synchronous clock based on FPGA has been applied in phasor measurement of a power system. It not only features high precision and high integrity, but also works stably as long as 6 hours when the GPS signal becomes ineffective.