Optimization of robust power oscillation dampers for DFIG wind turbines considering N-1 outage contingencies

This paper focuses on a new optimization technique of robust power oscillation damper (POD) for doubly-fed induction generator (DFIG) wind turbines considering N-1 outage contingencies. The POD with 2^nd-order lead/lag compensator and local input signal is placed with the voltage controller of DFIG so that the reactive power output can be modulated to damp out power oscillations. The optimization of POD parameters is formulated based on a mixed H₂/H_∞ control, and carried out under all system outage events such as line tripping, and load/generation shedding etc. The firefly algorithm is employed to obtain the optimal parameters of POD. Simulation study in an IEEE 9 bus system reveals that the proposed robust POD provides superior damping effect than the conventional POD against various system contingencies and uncertainties.