间歇性遮挡对光伏组件发电量影响的研究

当光伏组件或者光伏阵列中部分光伏电池受到间歇性遮挡时,输出伏安特性曲线呈现阶梯状,对应的功率电压曲线包含多个局域峰值,导致光伏阵列发电效率下降,系统发电量降低。为了正确评估该类问题,通过工程案例重点研究和分析了不同遮挡情况下光伏电池输出特性,建立MATLAB池板单元级、方阵级遮挡的计算仿真模型,统计出由于组件间歇性遮挡带来的系统发电量的损失,文中的仿真统计结果与实际系统发电量进行了比较,验证了该方法的可行性。文中最后提出了利用分布式MPPT方法挽回遮挡对系统发电量的影响,通过系统监控得知,分布式MPPT最高可挽回15.52%的发电量,具有较高的工程应用价值。

Study on the Influence of Intermittent Shielding on Power Generation of PV Module

When some PV cells of PV module or PV array are shielded intermittently,the output voltage-current curve has the feature of stepladder shape,and corresponding power-voltage curve contains multiple local peak values,which decrease efficiency and power generation of PV array.In order to evaluate the affected value properly,the I-U characteristic curve under different intermittent shielding is analyzed mainly through project case,and the simulation model of PV cell and PV array are built in MATLAB.Then the loss of power generation caused by intermittent shielding between components is calculated,and the power generation obtained by simulation is compared with that of practical system,which verifies the feasibility of the method.In the end,study shows that influence of shielding on system power generation will be overcome by distributed MPPT control method,and maximum salvage power generation will reach 15.52% through system monitoring,which has high engineering applications value.