Study concerning the optimization of the fuzzy controllers used for the resonant inverters command

Abstract

The difficulty that characterizes the resonant inverters analysis, modelling and command design is given by the nonlinearities of the system containing the inverter and the load. To obtain the needed dynamical performances supposes a good knowledge of the system and is based firstly on the inverter small signal model. This model can be obtained by imposing some simplifications and because of this reason it has a limited validity and strongly depends on the static operating point around which the linearization is made. This paper presents another solution for the resonant inverters command based on fuzzy command logic, which does not need a precise mathematical model and complicated calculations. This solution imposes only a qualitative understanding of system operation and the ability to extract a set of rules that characterize the system functioning. This paper contains a study of the influence it has the choice of membership functions and fuzzy command rules on the resonant inverter dynamic performances. For the developed simulations was used MATLAB software environment and it was followed fuzzy controllers behavior various perturbations. The obtained results allow the formulation of useful design rules for the fuzzy controllers.