IRIG-B码在继电保护装置中的应用

　　随着变电站自动化技术的发展，对变电站内时间的精确和统一提出了更高的要求。本文提出了一种采用IRIG-B时间码来对时的方案。在这种对时方案中，每个变电站只安装一个GPS接收装置，利用RS422/485总线传输IRIG-B码，保护装置对IRIG-B码解码器后，来设置自己的时间。本文还详细介绍了IRIG-B码的概念和原理以及用CPLD实现IRIG-B码解码器的设计思想和实现方法。IRIG-B码对时方式简化了回路设计，并且能够可靠地提供精确的时间信息，必将在电力系统中得到广泛的应用。

　　Abstract:

　　With the progress of automatic technology in transformer substations， requirements for unified and accurate time in a substation are put forward. An economic and accurate scheme to synchronize time by using IRIG-B code is presented in the paper. In this scheme， only one GPS receiver is used in every substation， and the IRIG-B code is transmitted by RS422/485. After decoding the IRIG-B code， the protection device can set its own time. The concept and principle of IRIG-B code are explained， and the particular method of decode IRIG-B code by using CPLD is stated in detail. The way to synchronize time with IRIG-B code can simplify the circuit design，and provide accurate the information of time，which will be widely used in power system.