DCS系统环路通信故障导致机组跳闸的原因分析及改进措施

Cause Analysis and Improvement Measures of Unit Trip Caused by Communication Failure of DCS System Loop

介绍某火电厂300 MW机组跳闸的发生过程及检查情况,指出DCS系统环路通信故障造成MFT继电器已动作信号误发是导致机组跳闸的主要原因。通过对MFT继电器已动作信号采用的通信传输方式和通信信号质检逻辑设计存在的隐患进行分析,提出了台账管理、逻辑设计、修订应急预案等防范措施,防止类似故障的重复发生。

By introducing the tripping process of 300 MW unit in a thermal power plant and the checking and analyzing process of its causes, it is pointed out that the main reason for the tripping event is the mistransmission of the MFT relay operating signal caused by the communication fault of the DCS loop.At the same time, through the analysis of the communication transmission mode adopted by the MFT relay operating signal and the hidden trouble existing in the logic design of communication signal’s quality inspection, the paper puts forward the preventive measures in the aspects of account management, logic design and emergency plan, so as to prevent the repeated occurrence of similar accidents and provide reference for the units with similar problems.