Improving the incremental conductance algorithm for two-stage grid-connected photovoltaic systems

Abstract

Efficiency of solar photovoltaic generation plants depends not only on internal operational conditions but also on external atmospheric conditions. Total efficiency is in uenced by various weather conditions such as cloudiness, temperature, and irradiation. In order to generate maximum energy, photovoltaic (PV) arrays should be operated at their maximum power point (MPP), varying external factors like partial shading and surface temperature and amount of radiation coming from the sun. In modern PV systems, maximum power point trackers (MPPTs) have been used in order to reach the MPP, changing with the factors given above. MPPT units are implemented to control DC-DC converters that are connected to terminals of PV arrays. MPPTs operate according to some algorithms to reach the maximum power level in various conditions. This study presents a new modification of the incremental conductance (IncCond) algorithm, one of the best-known algorithms, to improve total efficiency of solar energy conversion systems. The proposed modified algorithm is able to catch the new MPP quickly compared to the conventional type and oscillations are also decreased, reaching a new operating point.