LPPT control of a photovoltaic system under partially shaded condition

Abstract

The objective of this paper is to deal with the partial shading problem in the limited power point tracking (LPPT) control of a photovoltaic system. The normal LPPT controller can work only under uniform irradiance condition. Under partial shading, the P-V curve of the photovoltaic system becomes multi-modal. As a result, the operating point can be trapped at a local peak whenever there is a rise in the reference power command. In order to avoid the particular phenomenon, an efficient local peak detection scheme is developed. Therefore, the operating state of the system can be appropriately re-initialized based upon the identification of a local peak. The local peak detector proposed is carefully designed so as to minimize any false detection. Detailed simulation studies are carried out to verify the usefulness of the proposed local peak detection scheme.