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Summary In this paper, an improved direct torque control (DTC) strategy based on a fuzzy inference system is proposed to control a doubly fed induction generator (DFIG)‐based wind energy conversion system (WECS). The proposed method is based on increasing the number of sectors to 12 instead of six in the classical DTC (C‐DTC), and the use of a fuzzy inference system to generate the optimal voltage vector to apply to the rotor side converter (RSC). The proposed method aims to reduce the flux and torque undulations which are considered the main disadvantage of the C‐DTC and to control the power factor at the stator terminals by generating the referential rotor flux from the referential reactive power. The effectiveness of the proposed strategy is well tested by the simulation. Moreover, a total harmonic distortion (THD) analysis was performed for the rotor and stator currents waveforms. The results show a considerable reduction of the undulations for both flux and torque, and a significant reduction of the THD.

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Abstract:The transfer of the power from the PV generator to the load is not always optimal. The operating point of the characteristic of the said generator is strongly linked to the temperature variations, the solar irradiation and the load. In order for the module to provide its maximum available power, it’s necessary to permanently adapt the load with the photovoltaic generator. This adaptation can be carried out by inserting a DC-DC converter (boost) controlled by a “Maximum Power Point Tracking” (MPPT). The work is a comparative study of the power maximization methods incremental conductance, Hill climbing and perturbation and observation. Matlab is used to implement modeling and simulation tasks and to compare the efficiency and accuracy of execution for the selected MPPT methods. The simulation results for operating characteristics I-V and P-V for various cell temperature and solar irradiation closely matched manufacturer data sheet of the solar panel. Also, the algorithms described in this work have a considerable higher precision and it can be concluded that the output power of the PV module for the Incremental Conductance method is comparatively greater than the P&O and Hill Climbing method in a different conditions.