Authors: Wajdi Saad; Anis Sellami; Germain Garcia
Addresses: LISIER, ENSIT, TUNIS University, 5 Av. Taha Hussein, PB 56, 1008, Tunis, Tunisia ' LISIER, ENSIT, TUNIS University, 5 Av. Taha Hussein, PB 56, 1008, Tunis, Tunisia ' LAAS, CNRS, Toulouse University, 7 Av. Colonel Roche, F-31400, Toulouse, France
Abstract: Over the past few decades, the world demand for energy has risen steadily, forcing the world communities to look for alternative sources. Photovoltaic (PV) is seen as the most appropriate solution for this demand. In this context, this paper presents a robust terminal sliding mode control (RTSMC) method for maximum power tracking of stand-alone PV systems. The design method provides good robustness properties in the face of the system uncertainties and change of environment conditions. Starting from the mathematical dependence between the open-circuit voltage (Voc) and the optimal operating voltage (Vop), an MPPT design method is given. To eliminate the tracking voltage error, a RTSMC method is introduced thereafter. A pulse width modulator (PWM) is used to maintain the switching frequency constant. Compared to the P&O algorithm, the proposed methodology reduces the oscillations around the maximum power point (MPP) and provides better performance proprieties. Also, the simulations results prove the robustness qualities of the TSMC-MPPT design method.
Keywords: terminal sliding mode control; robust control; maximum power point tracking; MPPT; photovoltaic system.
International Journal of Modelling, Identification and Control, 2018 Vol.29 No.2, pp.118 - 126
Received: 25 May 2016
Accepted: 28 Oct 2016
Published online: 08 Mar 2018 *