Research on Improvement of C2 Signal Alarm in Nuclear Instrument System of PWR Nuclear Power Plant

To mitigate the negative impact of frequent C2 signal triggering caused by power range neutron flux fluctuations on the control of nuclear power units, this study analyzes the neutron flux fluctuation phenomenon and C2 signal triggering logic of the CPR1000 nuclear power plant. A nonlinear filtering scheme for C2 signal alarms is proposed, and this method is used to simulate typical plant conditions, studying the responses in both steady-state and transient states, as well as evaluating the impact on nuclear power safety. The research results show that the nonlinear filtering scheme does not adversely affect nuclear safety, can effectively alleviate the problem of frequent C2 signal alarms, and does not affect the transient response of the unit, making it suitable for widespread application.