Dynamics and control system design of an autonomous wind turbine

The dynamics of a 30 kW autonomous wind turbine (WT) driving a synchronous generator (SG) which supplies two reverse osmosis (RO) desalination units and a dump load are examined. The controlled dump load enables the control of electrical disturbances but the highly resonant, non-linear dynamic system determines the mechanical and electrical stresses caused by the wind speed disturbances. The desired dynamic characteristics have been achieved by specifying the required shaft stiffness and fluid coupling damping. The parameters of the proportional-integral (PI) controller influence the dynamic characteristics of the system and are carefully selected by a simple pole placement technique. The transient response of the system in large disturbances is recorded and analyzed using a developed detailed simulation program and the satisfactory response of the system in major disturbances is verified.