Study On A J-V Auto-measurement System For Multi-sample Solar Cells With Irradiance Calibration

With the increasing environmental pollution and the limited availability of fossil energy,the development of new energy is very rapid.Solar cells have become one of the hot research fields in the industry.In the process of development,the measurement of its J-V characteristics is undoubtedly the most important and most intuitive means of characterizing its performance.By testing the J-V characteristics of the solar cell,the short circuit current Isc,the open circuit voltage Voc,the fill factor FF,the photoelectric conversion efficiency ?,the optimum operating current Jm,the optimum operating voltage Vm,the maximum power Pm,the series resistance Rs and the shunt resistance Rsh can be obtained.These parameters are essential for the research,production and application of solar cells.The development of solar cell J-V characteristic measurement system has been gradually developed with the research of solar cells.The common test systems on sale are large-scale equipments,which have comprehensive functions,excellent performance,high test accuracy,and stable light.However,these systems are complex and expensive,and once a single package of the photovoltaic device can be measured.It is also necessary to regularly calibrate the output intensity of the solar simulator using an irradiation meter,thus the measurement accuracy is affected.Therefore,a J-V characteristic test system for solar cells used for measurement and research in university laboratories and general production sites for the initial test of photovoltaic devices,which is easy to use,low in price,and highly automated,has been developed,which has great research significance and popularization value.This system which used short-arc xenon lamp as the sunlight simulation light source,the digital source meter Keithley 2400 as the electronic load of the solar battery device to apply the applied voltage,combined the upper PC and the independently designed test software,with the multi-device switching circuit and the test base,realized multi-device automatic measurement.At the same time,based on the short arc Xenon lamp and its driving power,combined with the test software and the dimming circuit based on the Hamamatsu standard diodes,the system realized automatic calibration of the standard light intensity of the Xenon lamp before each measurement.Since the service lifetime of a xenon lamp is generally 600-1000 hours,the system also designed a function for counting the working hours of the xenon lamp.The working time of the xenon lamp is timed and maintained at the interface of the test software,and the alarm was issued when the working time reached its lifetime.By the way,the test system had a low cost and could be designed and modified according to different experimental requirements.