A Design of Partial Shading Detection Method and Global Power Point Searching Technique for Grid- Connected PV System Operating Under Partial Shading Condition

Abstract

The energy harvested by photovoltaic (PV) systems might be greatly reduced by partial shading conditions (PSCs). Nevertheless, it can increase if the PV system runs at the global maximum power point peak (MPPP), which is found using global peak finding tools. The multi-use of these tools, however, will decrease the output of PV systems because they push the PV system to run not within its power region during sweeping the I-V curve to locate the global MPP. So, the global peak finding tools must only be used as soon as a PSC happens. Here, an accurate method is outlined for discovering PSCs by watching out the sign of changes in voltage. It declares PSC occurrence when the sign of each successive voltage change remains the same for a defined number of consecutive changes. By incorporating a global MPP searching method with a partial shading condition detection (PSD) method, the PV system can operate at its greatest efficiency under PSC. So, the paper also proposes an integrated algorithm that combines a global MPP (GMPP) method based on Bald Eagle Searching (BES) with the partial shading detection method. The concept has been validated experimentally using a state-of-the-art real-time digital simulator RTDS to assess the GMPP search BES based method under PSCs. According to RTDS results, the algorithm finds the GMPP in all simulated PSC cases without fail.