Nuclear Techniques ›› 2020, Vol. 43 ›› Issue (4): 40003-040003.doi: 10.11889/j.0253-3219.2020.hjs.43.040003

• SPECIAL SECTION ON THE 11TH NATIONAL CONFERENCE ON NEW AND RESEARCH REACTORS (PART I) • Previous Articles     Next Articles

On-line monitoring of the thermal neutron sensitivity of Co-SPND detector

Hengkai ZHANG,Yuntao ZHAO,Ao LIU Jiguang LIU,Junwei ZHENG   

  1. State Key Laboratory of Nuclear Power Safety Monitoring Technology and Equipment, China Nuclear Power Engineering Co. , Ltd, Shenzhen 518172, China
  • Received:2020-02-17 Revised:2020-03-28 Online:2020-04-15 Published:2020-04-20
  • About author:ZHANG Hengkai, male, born in 1990, graduated from Harbin Engineering University, working on the commissioning and study of incore instrumentation system and control rod control system in nuclear power plant

Abstract: Background

Co-SPND (Co-Self Powered Neutron Detector) are used to measurement the neutron flux in reactor core in an EPR (European Pressurized Reactor) nuclear power unit, but their sensitivity of thermal neutron can not be calibrated in low power level (lower than 25%NP) and in real time operation.

Purpose

The study aims to find a new way to monitor the thermal neutron sensitivity for Co-SPND detector in low power level and in normal operation.

Methods

The relative thermal neutron sensitivity rate Cij of two Co-SPND detectors with radial symmetry arrangement was proposed as on-line monitoring parameters of thermal neutron sensitivity. It was the ratio of output currents of these two Co-SPND detectors. This method was applied and verified in the start-up and operation of an EPR nuclear power unit.

Results

The experimental results show the feasibility of this method in an EPR nuclear power unit.

Conclusions

The method is not only suitable for Co-SPND detectors, but also suitable for other types of SPND detector symmetrically arranged in core to monitor the thermal neutron sensitivity in operation.

Key words: Co-SPND detector, Thermal neutron sensitivity, Monitoring in operation, Radial symmetry relationship, The relative thermal neutron sensitivity rate

CLC Number: 

  • TL816+.3