Research On Digital Processing Algorithm And Experiment Of Signal Of Vanadium And Rhodium Self-powered Neutron Detector

The neutron flux is ankey physical parameter in the reactor.It plays an important role in the safety operation and control of the reactor.Vanadium self-powered neutron detector(VSPND)andrhodium self-powered neutron detector(RSPND)are widely used in the measurement of neutron flux in reactor because of their simple structure,small size,simple structure and long life.The slow response characteristics of output current signal of vanadium and rhodium self-powered neutron detector seriously affect the real-time response of the neutron flux measurement in the reactor,which are not conducive to real-time control and safety management of reactor.Inverse function calculation or various compensation methods are used to improve the real-time response characteristics of vanadium and rhodium self-powered neutron detector,which are beneficial to the use of them.The forward difference transform method,backward difference transform method,step response method and bilinear transform method of four kinds of digital processing algorithms were studied,and twice dynamic compensation method was proposed for VSPND,the response time of output signal of vanadium and rhodium self-powered neutron detectorare shortened effectively.However,the noise of the compensated signal is amplified by dynamic compensation,so the filtering effect of Butterworth low-pass filter on the compensated signal under different parameters is studied in this paper.Due to each of vanadium and rhodium self-powered neutron detector with an uncertain the prompt fraction,the dynamic compensation algorithm effects under different the prompt fraction are experimented,and the corresponding signal-to-noise ratio and response time are given.At the same time,the sampling interval of the signal is uncertain.In this paper,the compensation algorithm under different sampling intervals is tested experimentally,and the effects of sampling intervals on signal-to-noise ratio and response time are studied.The results show that the appropriate filtering parameters and sampling intervals can be selected according to the signal-to-noise ratio and response time.Therefore,it provides the feasibility for the rapid response of vanadium and rhodium self-powered neutron detectortothe measurement the neutron flux in the reactor.In the first chapter of this paper,the current research status of vanadium self-poweredneutron detector is briefly introduced.Chapter 2 mainly introduces the dynamic compensation mathematical model of vanadium self-poweredneutron detector.In the third chapter,the simulation results of dynamic compensation for vanadium self-poweredneutron detector are introduced,and the twice dynamic compensation method is proposed.Chapter 4 mainly introduces data acquisition card USB-231 and related software.And it also introduces the data acquisition interface based on LabVIEW software.Chapter 5 mainly introduces the experimental methods and results.