火电厂DCS系统信号抗干扰研究及实例

为解决影响火电厂安全稳定运行的DCS（分散控制系统）信号干扰问题,分析了DCS的5类干扰来源：系统内扰、电源干扰、传导干扰、接地干扰、辐射干扰,提出6种抗干扰措施：隔离设备、选择电源、选择电缆、敷设电缆、有效滤波、正确接地。并以某电厂2×300 MW机组为例,系统分析了该机组汽包水位和汽包压力信号非正常波动的原因及解决方法。最后提出火电厂DCS系统抗干扰设计、施工及运行过程中应注意的3点要求,为电厂相关技术人员提供参考和借鉴。

Research and application on signal anti-interference of distributed control system in thermal power plant

To solve the problem of signal interference in distributed control system(DCS) of thermal power plant,five interferences were analyzed.The interferences were system internal interference,power disturbances,conduction disturbances,grounding interference and radiation interference.Six anti-interference measures,which were isolation device,power selecting,cable selecting,cable laying,effective filter,properly grounding,were proposed.The causes and solutions for abnormal fluctuation of boiler drum level signal and drum pressure signal in a 2×300 MW unit were systematically analyzed.Three notable requirements in the anti-interference process of design,construction and operation of the DCS in the thermal power plant were proposed.The results can provide reference for the technicians of the power plant.