Dynamic performance of vector-controlled Doubly-Fed Induction Generators considering grid disturbances

To study the effect of network disturbances on the dynamic performance of a vector controlled Doubly-Fed Induction Generator (DFIG), a grid connected DIFG with wind turbine has been implemented in PSCAD/EMTDC software environment and three different network disturbances are considered. A 3-phase short-circuit fault is made to study the behavior of the system during a severe voltage dip. By controlling the reactive power and machine speed, power factor is improved and the system stability is maintained after the clearance of the fault condition. Two more disturbances, namely the increase of stator resistance, which can be caused by factors such as temperature and/or frequency increase, and the existence of noise in the measured signals of the current and machine speed caused by measuring sensors, are applied to the system. The simulation results show how the dynamic responses of the system are affected by these disturbances while the steady-state error in signals has increased and the power quality of the system has degraded.