遮荫下光伏发电数学模型的对比研究  

Comparative study of photovoltaic power generation math model under partial shading conditions

作　　者：肖文波[1,2] 余晓鹏 张华明[1,2] 吴华明[1,2] Xiao Wenbo;Yu XiaoPeng;Zhang Huaming;Wu Huaming(Jiangxi Engineering Laboratory for Optoelectronics Testing Technology, Nanchang Hangkong University, Nanchang 330063, China;Key Laboratory of Nondestructive Testing, Ministry of Education,Nanchang Hangkong University, Nanchang 330063, China)

机构地区：[1]南昌航空大学江西省光电检测技术工程实验室,南昌330063 [2]南昌航空大学无损检测技术教育部重点实验室,南昌330063

出　　处：《电测与仪表》2019年第10期56-61,共6页Electrical Measurement & Instrumentation

基　　金：国家自然科学基金资助项目(11264031);江西省青年科学基金(20143ACB21011);江西省教育厅科技项目(GJJ150729);航空科学基金项目(2017ZC56003);江西省图像处理与模式识别重点实验室开放基金(ET201908119);无损检测技术教育部重点实验室开放基金(EW201980090)

摘　　要：对比研究了光伏系统的两种局部遮荫发电模型,即幂律模型与四参数模型。结果首先发现,上述两种模型都和实验数据总体符合较好,但都有明显误差,原因在于,两种模型都是在简化下获得;其次,可以看出在低偏置电压下,两种模型都与实验数据符合较好,而在高偏置电压下,出现明显的误差,原因在于低偏置电压的时候,电池内部二极管未达到导通,流过二极管上的电流极小,可以忽略,电池可以看成是一个恒流源加上负载。随着偏压的增大,电池非线性效应显著增强,从而导致发电模型不适用'再次,注意到非均勻光照下,电池的工作状态受旁路二极管的影响不能由简单分析得到。旁路二极管是否处于阻断状态是一个渐变的过程,而不是简单的突变过程;最后,从理论与实验数据之间的均方根误差分析,可知四参数模型优于幂律模型,原因可能在于四参数模型考虑了光电流、反向饱和电流、理想因子、串联电阻的影响。In this paper,two kinds of power generation models of photovoltaic system under partial shading conditions( called as power law model and four-parameter model) are proposed and studied. Firstly,the results show that the two models are roughly equivalents to the experimental phenomena,although there are obvious errors between theoretical calculation and experimental data. The reason is that both models are obtained with simplicity. Secondly,it can be seen that both models are in good agreement with the experimental data when the cell is at low bias voltages,while the significant errors occur as the cell at high bias voltages. The reason is that,the cell can be regarded as a constant current source and load as the cell at the low bias,with the increase of voltage,the nonlinear effect of all kinds of solar cells is enhanced significantly which results in that the power generation model is not applicable. Thirdly,noting that the operating status of the each cell in the module cannot be obtained by a simple analysis when the module is at non-uniform light intensity. In fact,whether the bypass diode is in a blocked state is a gradual process rather than a simple abrupt process. Finally,it shows that the four-parameter model is better than the power-law model from root mean square error analysis. The reason may be that the four-parameter model takes into account the effect of photocurrent,reverse saturation current,ideality factor,series resistance.

关 键 词：光伏电池 发电模型 阴影遮挡 对比研究 非线性效应 

分 类 号：TM93[电气工程—电力电子与电力传动]