聚光集热器能流密度高速图像测量系统

High-Speed Image Measurement System for Energy Flux Density of Concentrating Collector

聚光型集热器的能流密度分布可以评价镜场和集热器的性能,通常使用的直接或间接测量聚光型集热器能流密度分布的方法存在精度较低或测量时间长等问题。针对这些问题,提出了一种基于图像处理的太阳聚焦光斑分析方法,利用可见光相机获取太阳能聚焦光斑图片,通过多层感知机计算出光斑各位置的辐照度,并提出了一种全新的能流密度分级测量方法,提高了系统对光斑辐照度测量的动态范围。该系统的平均绝对百分比误差在2.5%~3.5%范围内,测量周期约为2 s,不需要漫反射靶,具有精度高、测量速度快、测量时间短、受环境影响小等优点。实验结果验证了系统对不同辐照度范围的聚焦光斑能流密度测量的有效性和精确性,为聚光型太阳能集热器聚光点能流密度的测量提供了新思路。

Energy flux density distribution of the concentrating collector can be used to evaluate the performance of the mirror field and the collector.The direct or indirect measurement methods commonly used to measure the energy flux density distribution often suffer from issues such as low accuracy and long measurement times.To address these problems,we propose an image processing based method for analyzing the solar-focused spot.It utilizes a megacam to capture images of the solar-focused spot,the irradiance values at different positions of the spot are calculated using a multilayer perceptron,and a novel energy flux density grading measurement method is proposed to improve the dynamic range of irradiance measurement.The mean absolute percentage error of the system is in the range of 2.5% to 3.5%,and the measurement period is about 2 s.The system does not require a diffuse reflection target and offers advantages such as high accuracy,fast measurement speed,short measurement time,and low sensitivity to environmental conditions.Experimental results validate the effectiveness and accuracy of the system in measuring the energy flux density of focused spots in different irradiance ranges,which provide a new idea for measuring the energy flux density of concentrating collectors.