sensorless model reference adaptive control of dfig by using high frequency signal injection and fuzzy logic control

In this paper, a new sensorless model reference adaptive method is used for direct control of active and reactive power of the doubly fed induction generator (dfig). in order to estimate the rotor speed, a high frequency signal injection scheme is implemented. in this study, to improve the accuracy of speed estimation, two methods are suggested. first, the coefficients of proportionalintegral (pi) blocks are optimized by using krill herd algorithm. in the second method, the fuzzy logic control method is applied in the estimator structure instead of pi controllers. the simulation results for the proposed methods illustrate that the estimated speed perfectly matches the actual speed of the dfig. in addition, the desired slip value is achieved due to the accurate response. on the other hand, the active and reactive power responses have fast dynamics and relatively low oscillations. moreover, the fuzzy controller shows more robustness against the variations of machine parameters.