Model of photovoltaic cell circuits under partial shading

The PV-cell and natural energy production systems have been much attracted. Together with global warning and extensive applications of solar power electric generation, defects on PV-cell under the partial shading become interesting technical issue. This paper investigates the equivalent circuit model and its characteristics under the partial shading condition. And we have clarified the mechanism of PV-cell under the partial shading. As the extension of these considerations, we have proposed the new MPPT method (maximal power point tracking) for the sake of drastic energy generation improvement.