Small signal stability enhancement of DFIG based wind power system using optimized controllers parameters

• State space model of DFIG for small signal and transient stability is formulated.
• The controllers’ gains are optimized by PSO for dynamic performance improvement.
• Investigating the effect of optimized gains of controller on damping performance.
• The impact on the modes of oscillations with varying wind and strength of network.
• Enhancement in LVRT capability as per grid codes under fault and voltage sag.

This paper presents the state space modelling of doubly fed induction generator (DFIG) for small signal stability assessment. The gains of PI controller in torque and voltage control loop of rotor-side converter (RSC) are optimized by particle swarm optimization (PSO) to improve the dynamic performance of DFIG. These optimized parameters results in improved damping of DFIG and minimizes the oscillations in rotor currents and electromagnetic torque. The nature of modes of oscillations for DFIG integrated to infinite bus are analysed under different operating conditions such as varying wind speed and grid strength. The transient analysis with optimized parameters shows the enhancement in LVRT capability during voltage sag and three phase fault as desired by grid codes.