The maximum power point tracking (MPPT) plays a very important role in obtaining the maximum power of a solar panel because it ensures optimal operation of a photovoltaic system, regardless the conditions of irradiation and temperature. In this paper, we will introduce, a technique for improving and optimising the performances of a control system consisting of a photovoltaic panel, a buck converter and a load. This control is carried out by implementing two techniques of tracking the maximum power point (MPP). The first one, is based on the fuzzy logic control Takagi-Sugeno type ("TS fuzzy"), whereas the second uses the "Perturb and Observe" algorithm (P & O). Simulations of different parts of the system have been developed under Matlab / Simulink, enabling a comparison between the performances of the two controllers studied: "P&O" and "TS fuzzy". Both algorithms of command MPPT associated to these techniques are tested under the weather conditions of Agadir city located in the South of Morocco. So, the results obtained under various operating conditions, show a significant improvement in the performances of MPPT control of a photovoltaic system using the fuzzy logic controller.