Electromagnetic Method for Detecting Black Piece on Monocrystalline Silicon Photovoltaic Panels

In the process of installation and application of a photovoltaic (PV) power generation system, damage and replacement of PV panels are inevitable. The black piece is one type of malfunction that indicates complete damage to the PV cell and failure in electricity generation. The intuitive impact is that it affects the power generation of PV panels. For PV power plants with a large number of PV panels, PV panels are connected in series and parallel to converters, the monitoring of PV panels is limited, and each PV panel is not equipped with sensors, but only at the terminal of converters. Once a problem arises, it needs to be investigated PV panel individually. In this research, an electromagnetic detection method for monocrystalline silicon PV panels is proposed. First, the electromagnetic signals of monocrystalline silicon PV cells are simulated, according to this signal, a coil sensor is designed to pick up electromagnetic signals. Then, an experimental platform is constructed indoors, and the PV cell is covered with black tape to simulate the black piece. The electromagnetic signals are obtained and analyzed, and it has been concluded that the signal frequency of the black piece is at least twice that of a normal PV cell. Finally, the real damaged PV panel is measured and compared with the electroluminescence (EL), thermal imaging, and current–voltage (
$I-V$
) methods to verify the effectiveness of the proposed method.