针对基于以太网的工业测控系统时钟同步,探讨了低同步代价下实现较高同步准确度的问题.提出一定同步准确度下具有漂移补偿的远端时钟读取（RCR）时钟同步模型,它具有提高每一次同步准确度、简化远端时钟读取成功判断的特点,可降低整个系统同步的计算量.通过给出集成时间戳报文的数字锁相环漂移补偿,实现了一定同步准确度下具有漂移补偿的RCR时钟模型的同步架构及仿真.结果表明,该模型可将目前常见的基于报文传输延迟测算的时钟同步方法NTP的准确度至少提高一个数量级.

Aiming at the high-accuracy clock synchronization with low cost in the industrial measurement and control system based on Ethernet,this paper presents a RCR（Remote Clock Reading） clock synchronization model with drift compensation,which is predominant in the precision of synchronization and the simplification of synchronization judgment and computation.Then,the architecture of the model is presented by integrating Timestamp Digi-tal Phase-Locked Loop in drift compensation,and the corresponding simulation is performed.Simulated results show that,as compared with the conventional message delay-based clock synchronization method NTP,the proposed model is more accurate,with an accuracy increase of one order of magnitude at least.