An Improved Sliding Mode Control for Maximum Power Point Tracking in Photovoltaic Systems

Abstract

Tracking the maximum power point (MPP) has a great interest in the study of photovoltaic (PV) systems. This task is very difficult due to the non linearity of PV current-voltage characteristics which are dependent on the temperature and irradiation conditions. The sliding mode control (SMC) based MPPT with two different step sizes designed for Boost-type DC/DC converter method is investigated in this paper. The robustness of the proposed controller is tested under rapidly changing solar radiations. The SMC based MPPT is compared to perturb and observe (P&O) method and to incremental conductance (IncCond) method. The PV-MPPT system is simulated by Matlab/Simulink environment and verified by practical implementation within DS1104 R&D controller board. The simulation and experimental results are satisfactory and demonstrate that the new SMC can follow the PV peak power at different operating conditions with best performance.