High accurate synchronous clock based on GPS for power grid

At present,the stability of the clock working in the power system is very poor,and can't respond to the request of simultaneous measurement in the power system.In order to solve above-mentioned problems,a high accurate clock based on a quadratic regression model for crystal oscillator in synchronism with GPS-clock is designed in this paper,the square-error of GPS-clock and the accumulative error of crystal oscillator are estimated.With the accumulative error compensated,high accurate clock based on the CPLD is produced.