6. Conclusion
Simulation analysis for 5HP slip ring induction motor is done using Matlab/Simulink and models for battery
charging for both open loop and closed loop analysis. Power is extracted from DFIG in the super synchronous mode
of operation. In open loop simulation analysis, rotor speed is increasing continuously with increase in the wind
velocity. The battery charging voltage is also increasing beyond its defined rating, if rotor voltage of DFIG is more
due to high wind velocity. In closed loop simulation analysis rotor speed is maintained constant and the battery
charging voltage is being regulated using PI controller. 53V is considered as the reference value and compared with
the output voltage across the buck converter. PI controller is generating the error signal, and the switching pulses are
generated using PWM technique.