铑自给能中子探测器信号处理系统研究及中

Self-Powered Neutron Detectors (SPNDs) are crucial components for measuring neutron flux inside reactor cores. Due to their unique response mechanism, SPND signal currents are typically small and exhibit a delayed response. Furthermore, research on SPND sensitivity currently lacks experimental data obtained within reactors. This study focuses on Rhodium-SPNDs (Rh-SPNDs). By developing amplification circuitry for weak currents and implementing algorithms to process the delayed signals, a fast-response system for Rh-SPNDs was developed, reducing the detectors signal response time from several hundred seconds to approximately 3 seconds. Sensitivity irradiation tests were conducted on the Rh-SPNDs in the Minjiang Test Reactor (MJTR). The experimental results show that as the reactor power increased, the temperature in the test section also gradually rose, reaching 42.4C at full power. The output current of the Rh-SPNDs increased with rising reactor power, with higher currents observed on the "sunny side" (facing the core) compared to the "shady side". Finally, the thermal neutron sensitivity of the Rh-SPNDs was calculated. The thermal neutron sensitivities for the three SPNDs were: 1.6610 /A(ncm-2s-1)-1, 1.6810 /A(ncm-2s-1)-1, and 1.4410/A(ncm-2s-1)-1, respectively.