COMPARATIVE STUDY OF TWO CONTROL SCHEMES FOR MAXIMUM POWER POINT TRACKING STRATEGY OF A WIND SYSTEM

In this work, the maximum power point tracking (MPPT) of a wind system is achieved using two control schemes, either a decoupled control of speed and reactive power ((Omega-Q) control scheme) or an independently control of active and reactive power ((P-Q) control scheme). Indeed, the principal objective is the comparison of the two kinds of control schemes in terms of efficiency, costs, sizes, reliability and cumbersome. The control strategies are applied to the RSC of a wind energy conversion system (WECS) equipped by a DFIG. In addition, in the case of the (P-Q) control scheme, for the determination of the optimum stator active power reference in the MPPT mode, it is proposed to use the energetic balance sheet based on the rotor dynamic equation of the WECS. Elsewhere, the GSC is controlled to ensure a smooth dc bus voltage. The obtained MPPT results have been presented, discussed, and compared. Practically, the same results have been obtained. However, from a technical-economic point of view, it is shown that the (P-Q) control scheme is more reliable, cheaper, and less cumbersome comparatively to the (Omega-Q) control scheme.