الفهرس 
Why Renewable Energy
BDFRM Dynamic Model in Stationary FrameOnly 14 pages are availabe for public view
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Abstract
Brushless doubly fed reluctance generators (BDFRG) is one of attractive alternative generator types to the traditional and most commonly used doubly fed induction generator (DFIG) type due to its higher reliability, and lower maintenance cost. In addition, the BDFRM is capable to work in special environments such as offshore wind generation due to absence of slip rings which is not the case in DFIG. Keeping the same cost advantage of DFIG as its rival of using partially rated power electronics.
This thesis explains the construction and theory of operations of BDFRG and its different modelling techniques starting with the ABC detailed model using winding function theory, space vector dynamic model in the stationary (α-β) frame, and finally space vector dynamic model using two arbitrary rotating frames (ω) and (ω_r-ω). Simulation studies using MATLAB/SIMULINK are presented under different operating conditions to test the performance of these different models.
Another aim of this thesis is to represent BDFRG drive system and different control techniques implemented for WECS applications such as scalar or voltage/Hz control, field-oriented control (FOC), vector control (VC), and direct torque control (DTC). MATLAB/SIMULINK Simulation studies are conducted to investigate the performance of these control methods under different operating conditions. DTC shows the best performance among these control methods due to lower processing power requirements, fastest response specially during transient periods, and capability to handle grid disturbances with ignored effect on its performance.
Most of control systems of BDFRM require knowledge of rotor speed as a feedback signal specially if MPPT algorithms are applied. Thus, sensorless speed estimation algorithms are used as a solution to avoid negative reliability effects and increased system overall cost due to encoders and connecting cables. Sensorless speed estimation algorithms used for BDFRG are listed briefly showing their advantages and disadvantages. A novel sensorless speed estimation technique using least mean square (LMS) algorithm is introduced as a perfect solution to previous techniques problems. MATLAB/SIMULINK simulation study is conducted showing the superiority of the proposed technique over the traditionally used method utilizing primary winding flux linkage formula in stationary frame.