1000 MW核电汽轮机超速保护系统方案分析与优化

Analysis and Optimization of Overspeed Protection System in 1000 MW Nuclear Power Turbine

1000 MW核电汽轮机的电子超速保护系统的硬件检测回路需定期自检。自检时继电器轮流频繁动作,可能导致触点故障,因此有必要对电子超速保护系统进行分析和优化。介绍了1000 MW核电汽轮机电子超速保护系统的原理,分析了电子超速保护系统的三取二逻辑的实现策略和硬件回路保护方案,总结了系统的优点和存在的风险,并针对系统在自检过程中因叠加触点单一故障而导致误跳机的问题,提出了2套并线优化方案。对方案进行了分析对比,认为4路并线优化方案可以有效降低系统自检过程中的误跳机概率,提高运行可靠性。研究成果可为同类机型的汽轮机电子超速保护系统设计提供参考。

Regular self-inspection is necessary for the hardware detection circuit of the electronic overspeed protection system in 1000 MW nuclear power steam turbine.During the self-inspection,the frequent action of relays may cause contact faults,so it is necessary to analyze and optimize the electronic overspeed protection system.The principles of overspeed protection system in 1000 MW nuclear power steam turbine were presented,and analysis was carried out on the implementation strategy of two out of three logic and hard circuit protection scheme.The advantages and potential risks of the present protection system were summarized,and to solve the problem of false tripping caused by single contact faults occurred in self-inspection process,two coupling schemes were proposed.Analysis and comparison were carried out,and it was concluded that the probability of false tripping during self-inspection of system could be effectively reduced adopting the four-way coupling scheme,so the improvement of operation reliability could be realized.The research results can provide reference for design of electronic overspeed protection system for similar types of steam turbine.