Étude des comportements chaotiques dans les convertisseurs statiques

This thesis deals with the analysis of chaotic behaviors in serial multicellularconverters. These switching systems can have a variety of complex phenomenaassociated with bifurcations and chaos. Knowing that a power converter that has a purely dissipative load cannot generate chaotic behavior, we've in the first part of this thesis, we connected a two-cell chopper to a nonlinear load not strictly dissipative and we've analyzed its behaviors by using some basic dynamic properties and thus presented the routes to chaos. The end of this part was devoted to the study of the 5-cell chopper which is a generalization of the two-cell chopper. In order to eliminate the chaotic behavior, the second part was devoted to the synthesis of a controlled law based on hybrid modeling of Petri nets for the regulation of capacitor voltages and current load.Les travaux de cette thèse portent sur l'analyse des comportements chaotiques dans les convertisseurs multicellulaires séries. Ces systèmes à commutationpeuvent présenter une variété de phénomènes complexes liés à des bifurcationset au chaos. Sachant qu'un convertisseur de puissance qui a une charge purementdissipative, ne peut générer un comportement chaotique, nous avons dans la première partie de cette thèse, connecté un hacheur à deux cellules à une charge non linéaire non strictement dissipative et nous avons analysé ses comportements à l'aide des propriétés dynamiques de base et présenté les routes vers le chaos. La fin de cette partie a été consacrée à l'étude du hacheur à cinq cellules qui est une généralisation du hacheur à deux cellules. Afin de supprimer le comportement chaotique, la deuxième partie du travail a été consacrée à la synthèse d'une loi de commande hybride basé sur la modélisation par réseaux de Petri pour la régulation des tensions des condensateurs flottants et du courant de charge

Modeling and Control Design Based on Petri Nets for Serial Multicellular Choppers

International audienceThis paper deals with a control proposal for serial multicellular choppers. The proposed scheme takes advantage of the continuous and discontinuous chopper operation, and introduces the use of two Petri nets (PNs) to carry out the control action. The first PN generates the needed voltage level to assure the output reference current tracking, while a second PN solves the problem of capacitor voltage balancing, using switching state redundancies. Also, a stability analysis based on a Lyapunov function is used to ensure the convergency of the states under the commutation rule. The main advantage of this approach is the integration of the continuous and discrete dynamics through PNs, which directly drives the converter power semiconductors. Furthermore, this proposal could lay the basis for future studies in the design of converter controllers using the formal analysis tools offered by PNs. Experimental results from four and five-level choppers are used to emphasize the performance and the effectiveness of the proposed control scheme

Modeling and Control Design Based on Petri Nets for Serial Multicellular Choppers

International audienceThis paper deals with a control proposal for serial multicellular choppers. The proposed scheme takes advantage of the continuous and discontinuous chopper operation, and introduces the use of two Petri nets (PNs) to carry out the control action. The first PN generates the needed voltage level to assure the output reference current tracking, while a second PN solves the problem of capacitor voltage balancing, using switching state redundancies. Also, a stability analysis based on a Lyapunov function is used to ensure the convergency of the states under the commutation rule. The main advantage of this approach is the integration of the continuous and discrete dynamics through PNs, which directly drives the converter power semiconductors. Furthermore, this proposal could lay the basis for future studies in the design of converter controllers using the formal analysis tools offered by PNs. Experimental results from four and five-level choppers are used to emphasize the performance and the effectiveness of the proposed control scheme