Nuclear Reactor Doubling Time Calculation Using FIR Filter

In nuclear reactor engineering, reactor doubling time is generally applied to indicate the change of power level and usually provided by a nuclear instrumentation system (NIS). In a digital NIS, current signal from neutron detector is pre-amplified and conditioned into voltage signal which is proportional to the power level of nuclear reactor, and then is acquired and processed by a digital computer in the NIS. The measurement noise contained in the acquired voltage signal will cause a lot of uncertainty in the reactor doubling time calculation result. In this paper, the sensitivity analysis of nuclear reactor doubling time calculation is investigated. A calculation algorithm of reactor doubling time for digital NIS is proposed based on FIR Filtering techniques, and two filtering schemas to calculation reactor doubling time are given based on the FIR filter. A Hard-In-Loop (HIL) experiment environment was built to verify the discussed calculation algorithm. The experimental results show that the calculation algorithm developed can suppress the influence of measurement noise on calculation result to recover the signal's original features, and can provide us with good on-line calculation result.