Wide Range Of Nuclear Measurement Instrumentation Developed

When nuclear reactor is running, the neutron flux rate can vary from 10 to 11 orders of magnitude. In order to monitor this extremely wide range efficiently, traditional method splits this wide range into smaller segments and adjust it accordingly. However, systems built on this method are highly complicated due to the use of a large amount of different detectors, amplifiers and power suppliers. To simplify the system design for the monitoring of this extremely wide range of neutron flux rate, many feasible designs have been proposed in this field. Among them, the Campbell electric circuit is the most widely used method in China. Similar to the traditional method, this method also needs to overcome the problem of having too many components, complicated circuit and the lack of on-line self-checking ability.This paper is organized as follows: first, we analyzed the causes for the problems common to many domestic nuclear monitoring systems. Based on this analysis, we proposed the replacement of the widely used resistor-based A/D conversion method with the integral A/D conversion method in order to resolve the fundamental problem; we designed and implemented a fully digitalized experimental nuclear monitoring system with wide range that utilized the integral A/D conversion method and this also reflects the full-digital trend of the design of nuclear reactor control system. We elaborated on the design idea, design flow and method to implement the system in hardware and software. Last, we described further plans that addressed some problems found in the verification electric circuit.