Small signal stability analysis and optimised control of a PMSG-Based wind turbine using differential evolution

Abstract

Small signal stability of power system is well analysed in the past few decades, but much attention has not been paid yet for the systems with wind turbines. This paper presents a detailed mathematical model to perform the small signal analysis of a direct-drive permanent magnet synchronous generator (PMSG). Based on the eigenvalue trajectories with varying controller parameters, the limits of proportional integral controller gains are decided within which the system remains stable. Further, the differential evolution algorithm is applied to an objective function based on eigenvalue shifting to find out the optimal values of the controller gains within the decided limits. The time domain simulation results with the optimised controller gains are obtained using MATLAB software. The results demonstrate the stability of the system after initiating a small disturbance in terms of wind speed variation.