Analyse et commandes des convertisseurs multi-niveaux pour un générateur photovoltaïque connecté au réseau électrique

This PhD work, prepared at SATIE laboratory, is part of the promotion of solar photovoltaic (PV) energy. In this work, we are particularly interested in design and control of the grid-connected PV system in a context of use in Chad where cost, reliability, efficiency, and energy quality issues of the system should be taken into account. The considered grid is a low voltage grid (220 V) with a frequency equal to fifty hertz (50 Hz) but likely to vary, in which a power of five point two ( 5.2 kW) is injected. A design method of the filter passive to reduce the filter elements is proposed firstly. In order to reduce manufacturing cost and volume of the passive filter, we apply a technique consisting of dividing each inductance value and making it in several small inductances in series. This technique optimizes the conventional PV system. Then, we proposed a new grid-connected PV system architecture using a multi-level inverter. The adaptation of this innovative structure has reduced the manufacturing cost of passive filter by nearly 40 % compared to the classical optimized system. Finally, a decoupled PQ control, using a phase locked loop for sysnchronization, has been designed and applied for both systems. It is well adapted to the system with multilevel inverter.