在空间环境中太阳电池的涂层会发生退化,从而影响航天器的飞行寿命,因此研究能够测量涂层光学透射率变化的系统具有重要意义.使用三结太阳电池作为探测器接收光能量;设计光电流检测电路,对太阳电池输出电流进行电流-电压变换,放大,滤波和模数转换,最终输入上位机处理;运用双通道比对测量技术,比较有玻璃和无玻璃的三结太阳电池光电流测量值,计算出玻璃样片在三结太阳电池响应谱段内的整体透射率;使用热电阻传感器检测太阳电池工作温度以消除温度变化带来的误差.通过实验测得系统的测试相对误差约为0.1%,测量不确定度小于0.15%.
The degradation of solar cells' coatings in space environment will shorten space aircraft's fight life.So the research of the system which can measure the coatings transmittance's change is important.The transmittance measurement system was constructed by two triple-junction solar cells,one of which was covered with the glass sample and another was not.The triple-junction solar cells were used as detectors to measure solar flux.The photocurrent measurement circuits convert the photocurrent to analog volt,which will be multiplied and filtered.And the volt was translated to digital signal,which is transferred to the computer finally.The photocurrent signals of two triple-junction solar cells were acquired to calculate the overall transmittance in the solar cell responding spectrum,by using two channels comparing measurement method.The solar cells operation temperature was monitored by platinum-chip temperature sensors,in order to avoid measurement error which is induced by temperature change.The measurement relative error of system is about 0.1%,and the measurement uncertainty is less than 0.15%,which is proved by experiment.