乳品成分近红外光谱测量系统及其可靠性热设计

Near-Infrared Spectral Measuring System of Milk Constituents and its Reliability Thermal Design

论述了基于声光可调谐滤光器 (AOTF)的乳品成分近红外光谱测量方法 ,并针对测量系统进行了可靠性热设计。通过对测量系统进行故障树分析 (FTA) ,从结构材料的热平衡入手针对光源部件的故障隐患进行了结构热设计 ;同时 ,针对系统核心分光器件—声光可调谐滤光器AOTF晶体采用PID调节方式的单片机系统进行了恒温控制。通过对测量系统进行优化 ,部件可靠性及光谱稳定性相应提高 ,数据表明 :系统测量光谱重复性变异系数CV 值由 0 .5 %降低到 0 .1%。

Based on Acoustic Optical Tunable Filter (AOTF) spectroscopic technique, the measuring feasibility for principal milk constituents by Near-Infrared spectroscopy was investigated. Combining developing of the measuring system, reliability thermal design methods suited for the system were discussed and applied. On the basis of making Failure Tree Analysis to the system, Thermal design in structure was made to incipient fault of light source from the thermal equilibration of the structural materials. At the same time, thermostatical control was adopted to the key spectroscopic device-AOTF crystal by chip microcomputer system with PID control. By means of optimum design to the system,reliability of the device and spectrum stability of the system were also improved accordingly. The results of this study indicated that the coefficient of variation of repeatability of spectrum reduced to 0.1% from 0.5%, which showed that accurate, rapid, and nondestructive determination of milk composition could be successfully performed by using near infrared spectroscopy analysis(NIRA) and reliability design techniques.