A method to eliminate signal delay of self-powered neutron detector

Abstract

The invention provides a method for eliminating the signal time delay of a self-powered neutron detector. The method comprises the following steps: obtaining a nuclear reaction equation of a neutron and an element of the self-powered neutron detector, a [Beta] decay equation of an activating element and a reaction equation of a [Gamma] ray; establishing a state space model of the reaction of the element of the self-powered neutron detector and the neutron as well as the [Gamma] ray; carrying out accurate discretization on the state space model; collecting a current signal of the self-powered neutron detector which eliminates a background signal of a cable, and combining with an adaptive filtering or kalman filtering method with the discretized state space model to calculate the current signal subjected to time delay elimination; and according to the current signal subjected to time delay elimination, calculating the fuel consumption and the sensitivity of the self-powered neutron detector, and obtaining a corrected neutron flux according to the sensitivity of the self-powered neutron detector. The method can eliminate time delay characteristics, which are caused by a half-life period, of the self-powered neutron detector, and can quickly reflect the change of the neutron flux.

Description

technical field [0001] The invention relates to the technical field of nuclear measurement, in particular to a method for eliminating the signal delay of a self-powered neutron detector. Background technique [0002] Self-powered neutron detectors have the advantages of simple structure, small size, low cost, and no need for external bias power supply. The fuel consumption is different and changes continuously, and the response of the current output also has a certain delay. This makes it difficult for long-term use and accurate measurement of neutron self-sufficient energy detectors because the sensitivity changes too quickly. Through the mathematical modeling of self-powered neutron detectors and the use of corresponding delay elimination algorithms, the response speed of self-powered neutron detectors can be improved to a certain extent, so as to meet the requirements of real-time monitoring of neutron flux in the core. [0003] However, the existing research on delay e...

AI Technical Summary

Problems solved by technology

[0003] However, the existing research on delay elimination only analyzes the delay elimination for a certain element, and does not evaluate the commonality of the current and its mechanism generated by the cable under neutron irradiation; secondly, the discrete method adopted It is the Euler discrete method, the results obtained by this method are very different due to the different sampling time, which also makes the calculation process have the risk of instability; moreover, the factor of fuel consumption is not considered comprehensively, and the self-supplied neutron detector After a certain period of use, the number of elements in the emitter will continue to decrease, resulting in differences in current values ​​under the same neutron flux

Images