Today, thermoelectric generators (TEG) are of great interest since their prices are falling and more areas of applications have appeared. In order to increase the TEG’s low voltage and to enhance performance of the thermoelectric power conversion system, this paper presents a direct adaptive sliding mode MPPT based on incremental conductance (INC) principle applied to a modified high voltage gain SEPIC converter. Mathematical modeling and computer simulations for the considered system are carried out. A comparison is made between the proposed method, the basic sliding mode (SM) and the Perturb and Observe (P&O) algorithm. The proposed tracker has been implemented to ensure that the TEG works at its maximum power regardless of the load it feeds and the temperature gradient between its two sides. The results of this study showed that the TEG’s voltage can be boosted from two to twenty times, an energy transfer efficiency over than 99% and an aptitude to track the maximum power point (MPP) at diverse working conditions perfectly with high performance including low convergence time and less oscillations.

Keywords: Thermoelectric applications, Maximum power point tracking (MPPT), Direct adaptive sliding mode, Single-ended primary-inductor converter (SEPIC), High voltage gain converter