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Summary A fuzzy logic peak current control is proposed to extract the maximum power from a wind turbine and reduce the total harmonic distortion of the generator current. This system uses a permanent magnet synchronous generator and a boost rectifier operating in discontinuous conduction mode (DCM). The proposed method includes a fuzzy logic controller, used for deriving the optimum value of DC‐side current, that will be used as reference for the peak current controller. A simulation study is done to verify the validation of the proposed method, also to show the advantages of the system designed to operate in DCM compared with that designed to operate in CCM.

This paper deals with the stability analysis of a class of switched bond graphs where all the storage components remain unchanged and in integral causality under mode switching. These properties assure the existence of a unique energy function common to all the switching modes, and the non occurrence of state jumps or discontinuities in the switched system trajectories. A result on stability of equilibria in the sense of Lyapunov is presented. The derivation of this result is done using a bond graph technique for Lyapunov stability analysis (previously developed by one of the authors of this paper) in association with results available in the literature related to the satisfaction by a candidate Lyapunov function of a sequence nonincreasing condition for the state trajectories of a general autonomous switched system. Because of its versatility, the Switched Power Junction formalism is chosen in this paper to model and simulate the commutations in the bond graph domain.

In the last decades, researchers and scientists have been trending towards photovoltaic (PV) solar energy research as one of the noteworthy renewable energies. As a matter of fact, the need for a laboratory system devoted to performing measurements and experimentation on PV systems is being increased. The PV array emulator is designed to accomplish this task by reproducing accurately the electrical behavior of real PV sources. The present paper proposes thus a new control and design of PV array emulators. It is based essentially on a hybrid Damping Injection controller. The proposed control strategy circumvents obviously the existing PV emulator's limitations in terms of accuracy, speed and partial shading emulation. Several results are given and discussed to show the efficiency of the proposed system to emulate PV modules and different PV array configurations under uniform solar irradiance and partial shading conditions.