Voltage quality enhancement of grid-connected wind turbine generation system through series compensation: A probabilistic approach

This paper proposes a series compensation technique to enhance voltage quality for grid-connected doubly-fed induction wind generators (DFIG). The approach is based on statistical means and the purpose is to determine the optimal power capacity of the compensating device. Wind speed variations are assumed to be of Rayleigh distribution function. From known rotor and wind speeds relationship, rotor speed probability distribution is obtained. The resulting injected wind power and thus the terminal voltage variations are evaluated. The series compensator capacity to mitigate the voltage variations is then determined, with the capacity also expressed in terms of the confidence level in meeting specified voltage quality.