光纤纵差保护同步接口转换电路设计

Circuit design of synchronization interface converter in fiber-optical current differential protection

在光纤纵联差动保护中,数字信号处理器DSP接收电力线路远端测量到的通过光纤传送过来的电量信息并把电力线路近端测量到的数据传送给远端的DSP,DSP把测量到的数据和传送过来的数据进行分析比较后决定是否采取保护动作。DSP使用外部数据总线同外设交换数据,而光端机处理的数据是同步串行数据,所以两者之间需要一个协议转换电路,把光端机的符合G.703协议的数据和信号处理器的总线数据相互交换。本文介绍了一种设计方法,使用通信控制器SAB82532作为协议转换芯片,对SAB82532外部管脚和内部寄存器进行配置,实现数据链路层协议的转换和数据透明传输。通过两个装置之间正常通信的数据分析,证明了该电路实现了DSP和光端机之间数据交换的功能,运行可靠,性能稳定。

In the process of fiber-optical current differential protection, the digital signal processor （DSP） receives the electric quantity values transmitted by the optical modem from the other side of the power line, and transmits electric quantity values measured from itself to the other. DSP analyses the data measured from both sides, and give the decision whether to take action of protection or not. DSP exchanges data with its peripherals Data Bus, while the optical modem sends or receives data in serial synchronization, so a protocol interface converter is needed to exchange data from G. 703 protocol with data from Data Bus. The paper presents a circuit using communication controller SAB82532 as the protocol convert chip. By proper configuration to the exterior pins and interior registers of SAB82532, data link layer protocol converting and data transparent transition could be achieved. The data analysis of the normal communication between the tow devices indicates that the convert circuit realizes the communication between DSP and the optical modem and the circuit is capable of operating reliably and stably.