Image recognition method for shadow shielding of photovoltaic cell

The invention belongs to the field of photovoltaic power generation, and particularly relates to an image recognition method for shadow shielding of a photovoltaic cell. In order to find out the position of the sheltered photovoltaic cell, the method adopts a sub-pixel image matching method, and realizes dual functions of sheltering recognition and sheltering area calculation through a quadtree image segmentation method in combination with the characteristics of a photovoltaic power station. Firstly, when a power station operates normally, an original image of the photovoltaic power station is obtained and serves as an original sample image; then segmenting the image into four equal parts, matching the image to be detected with the original sample image by adopting a sub-pixel gradient matching algorithm, and finding out a minimum matching value; and calculating a mean value and a mean difference value of each image pixel by combining a mean square error threshold value judgment method, and when a calculation