计及旁路二极管效应的太阳能模组性能评估

Performance Evaluation of Photovoltaic Module With Bypass Diode Effect

为避免功率失配损失,太阳能模组一般都配置旁路二极管,提供一个能量散逸的途径。基于这种配置提出一种新的太阳能模组性能评估算法。依据实际旁路区段配置建立网络方程,通过牛顿-拉夫逊非线性迭代方法实现拓扑求解,继而获得模组的整体性能。在用制造商标准测试数据验证了该评估算法的有效性后,进一步考察各种阴影场景下的模组整体性能,并给出全局最大功率点(maximal power point,MPP)位置随辐射强度变化时的定性结论。理论分析和仿真结果表明,由于多辐射强度导致功率多峰值的存在,常规最大功率点跟踪(maximal power point track,MPPT)算法可能会因为只能检测到MPPT伪极大值点而失效;而且,旁路二极管的合理配置对太阳能模组性能有很大影响。

Photovoltaic modules are often configured with bypass diodes for providing energy releasing route to Prevent power mismatching losses. A novel algorithm for photovoltaic module performance evaluation was presented. With network equations established according to practical bypass configuration, performance of whole module could be achieved through topology solution with nonlinear iteration of Newton-Raphson method. After testifying the validation of the algorithm proposed with manufacturer＇s data, cases with different irradiation conditions were investigated for charactering overall module performance, and some qualitative conclusions of global MPP positions were. also put forward. The theoretic analysis and simulation results show that traditional MPPT algorithms may only detect false maximum in the cases with multi power peaks for multi irradiation conditions. Moreover, rational configuration of bypass diodes affects the performance of total photovoltaic modules greatly.