Contribution a l'etude des filtres hybrides de puissance utilises pour ameliorer la qualite de l'energie dans le reseau electrique de distribution

The use of power converters is increasing due to their utility for various forms of energy and ease of control. However, they absorb non-sinusoidal currents and thereby introduce currents and voltages harmonics in electrical distribution network. The presence of harmonics in the system results in several effects including increased heating losses in transformers, motors and lines, low power factor, torque pulsation in motors and poor utilization of distribution wiring and plant. Electric distributors must deliver electric energy to the electricity users at acceptable levels of service quality, which respect the limits imposed by IEEE 519-1992 and IEC 61000.3-2/4. Several solutions are used, among them the active filtering, which is the most used, but there are specific disadvantages, including its cost and its high design for industrial applications. Traditionally, passive filters have been used to eliminate specific harmonics and improve the power factor, but their bulky size, limited compensation ability, and susceptibility to resonance with the source impedance constitute a major drawback. These problems can be limited simultaneously by using the shunt hybrid filter and the hybrid passive filter. The aim of this thesis is to propose some solutions to improve the power quality: In this context, a new hybrid passive filter configuration have been proposed to compensate load harmonics, correct power factor, eliminate the chances of series and parallel resonance and eliminate large variation of power factor and terminal voltage with varying loads under stiff and distorted source conditions. The second solution involves modeling of the three-phase shunt hybrid filter, which helps to apply the advanced control technique in order to improve the static and dynamic performances. Finally, an economical solution for a new topology of three-phase series hybrid filter is proposed in order to handle the voltage dips, the sags, the voltage harmonics, the currents harmonic and the power factor.;Key words: Shunt active filter; shunt hybrid filter; series active filter; series hybrid filter; passive hybrid filter.