Investigation of Dynamic Behaviour of Double Feed Induction Generator and Permanent Magnet Synchronous Generator Wind Turbines in Failure Conditions

The variable nature of the wind significantly affects the generation of electrical energy and integrating large power wind farms into the grid can cause electrical quality problems. The increase in the number of wind turbines connected to the grid is resulting in electricity quality problems including voltage instability and difficulties in reactive power and frequency control. This study investigates the resilience of two forms of wind turbine, the permanent magnet synchronous generator (PMSG) and double-feed induction generator (DFIG), to disturbances that may occur in the network, such as symmetrical and non-symmetric short circuit conditions, and voltage drops. Models of PMSG and DFIG wind turbines have been developed in the MATLAB-Simulink environment and simulated operating at nominal power level for the same network conditions and wind speed. The simulation was then used to investigate the dynamic response of the wind turbines in the case of phase-ground, phase-phase-ground, and three-phase-ground short circuit failure, and voltage fluctuations, in order to determine which generator system has greatest benefit for electrical power quality. The DFIG wind turbine system was found to reach nominal active power faster than the PMSG wind turbine system. In addition, the frequency converter for the PMSG wind turbine system was more affected by failures in the power grid resulting in excessive DC bus voltages.