分布式系统高精度时钟同步算法及其实现

High-Precision Clock Synchronization Algorithm for Distributed System and Its Realization

时钟漂移与传输延时的不确定性是分布式系统时钟同步中一个不容忽视的问题,它直接影响同步精度．为此,充分考虑两者的影响,基于锁相环原理将PID调节与线性补偿相结合,提出了一种高精度时钟同步算法．采用RTLinux构建了具有时间触发机制的工业以太网实验平台,并在该平台上对所提出的同步算法进行实验研究,得到了网络延时参数的分布曲线和同步性能曲线等．结果表明,该同步算法有效地抵消了时钟漂移,抑制了网络延时的不确定性,获得了更高的时钟同步精度．

Clock drift and undetermined characteristic of transmission, will deteriorate the precision of clock synchronization of distributed system. To improve the precison, based on the phase locked loop, a new clock synchronization algorithm is presented, which combines the PID control and line compensation. And to test the algorithm an industrial Ethernet system with time triggered mechanism is developed and RTLinux is taken as its operating system. The distribution of network delay and the synchronization performance curves are obtained. The results of the experiment prove that the presented synchronization algorithm eliminates the effect of clock drift, reduce the undetermined factors and gets higher synchronization precision.