大亚湾核电站数字化改造项目关键敏感设备降级措施研究

Research on Degradation Measures of Critical Components in Daya Bay Nuclear Power Plant Digital Transformation Project

大亚湾核电站模拟控制系统由分立式电气元件通过硬接线集成,计划在30 a大修期间进行数字化改造,由于受模拟平台功能限制,设备单一失效对所在控制回路影响巨大,大量仪控设备被识别定性为关键敏感设备。全面降低关键敏感设备数量是大亚湾核电站数字化改造项目的关键目标,本项目以核岛重要控制回路——稳压器水位控制回路为研究对象,对关键敏感设备降级措施进行了系统研究和实践应用,利用改造后数字化控制系统(DCS)自动表决功能和故障诊断功能,提出了测量通道表决优化方案、输出通道双冗余设计方案;利用接口最优原则,将稳压器水位控制回路主调和辅调集中至一个功能子组,取消了大量跨子组接口。以上措施的应用,使稳压器水位控制回路仪控关键敏感设备由17个降至0个,全面提升了控制功能可靠性,降低了电厂设备管理成本,为实现项目关键目标提供了重要参考方案。

The analog control system of Daya Bay Nuclear Power Plant consists of discrete electrical components integrated by hard wiring,and it is planned to undergo digital transformation during the 30a overhaul.Due to the functional limitation of the analog platform,the single failure of equipment has a great impact on the control loop,and a large number of instrumentation and control devices are identified as critical components.Reducing the number of critical components is a key goal of the Daya Bay Nuclear Power Plant Digital Transformation Project.The Project takes pressurizer water level control loop—the important control loop of nuclear island as the research object and systematically studies and practically applies the degradation measures of critical components.By using the automatic voting function and fault diagnosis function of the reconstructed digital control system(DCS),the voting optimization scheme of measurement channel and the double redundancy design scheme of output channel are put forward.Using the principle of interface optimization,main control unit and auxiliary control unit of the pressurizer water level control loop are concentrated in a functional subgroup,and a large number of cross-subgroup interfaces are cancelled.With the application of the above measures,the number of critical components for instrument control of the pressurizer water level control loop has been reduced from 17 to 0,which has comprehensively improved the reliability of control functions,reduced the management cost of plant equipment and and provided an important reference scheme for achieving the key objectives of the Project.