The local and global behavior of the positive solutions of the difference equation
was investigated, where the parametersα,βandγand the initial conditions are arbitrary positive numbers. Furthermore, the characterization of the stability was studied with a basin that depends on the conditions of the coefficients. The analysis about the semi-cycle of positive solutions has end the study of this work.
The present paper deals with the modeling and control of Wind Energy
Conversion System WECS based Doubly Fed Induction Generator DFIG using the slip
energy recovery principle. The proposed drive system uses a Matrix Converter
(MC) to transfer the slip energy of the rotor into the mains instead of using cascaded ac-dc-ac converter whilst the stator
side is fixed to the grid. Operation at both sub-synchronous and
super-synchronous regions is possible with the proposed drive system. The
different level control strategies for maximum power point tracking and
active-reactive power are discussed. Simulation results of the proposed doubly
fed induction generator drive system show the good performance of the control
system strategy for both transient and steadystate conditions.