Sampling clock synchronizing method and system

Abstract

The invention is applicable to the field of industrial control and provides a sampling clock synchronizing method. The method comprises the following steps of: receiving crystal oscillator pulse signals provided by an external crystal oscillator and generating count pulse signals; receiving the count pulse signals for counting, and outputting sampling pulse signals after the counting of a preset counting quantity N is finished; receiving externally-input time pulse signals, and counting errors of the count pulse signals within a clock pulse signal period and between the clock pulse signal period and a sampling pulse signal period; and changing the preset counting quantity N according to the errors. By adopting the external stable clock pulse signals, the sampling clock synchronizing method can be used for adjusting the inherent errors of the crystal oscillator pulse singles and the errors caused by the factor that the count pulse signals trigger the sampling pulse signals under the influence of temperature change of work environments, so that the errors of crystal oscillator frequency can be reduced to the greatest extent, the effect of the accumulated errors on a sampling pulse can be eliminated, and the error accumulation of a sampling pulse clock is overcome.

Description

technical field [0001] The invention belongs to the field of industrial control, in particular to a method and system for realizing sampling clock synchronization. Background technique [0002] In the construction of the smart grid, many places have very high requirements for the synchronization of remote data acquisition, such as between the merging units in the digital substation, and between the PMU (Phasor Measurement Unit, phasor measurement unit) in the wide-area vector measurement system , Fault recording devices between different substations, etc. [0003] At present, there are generally two ways to achieve data synchronization between acquisition devices: one is to use the same sampling pulse among multiple devices, and the same sampling pulse is connected to each acquisition device through hardware connection, so that the sampling of each device is synchronized, such as figure 1 shown; the other is through a unified clock pulse signal (such as GPS clock, Beidou cl...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the embodiments of the present invention is to provide a method for synchronizing sampling clocks, which aims to solve the problems of error accumulation, hardware requirements and high cost of traditional sampling pulse clocks

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