Blade-Shaft Torsional Oscillation Minimization of Wind Turbine Generator System by Using STATCOM/ESS

In this paper, blade and shaft torsional oscillations of wind turbine generator system (WTGS) are analyzed when a network disturbance occurs in the power system. Many studies have been reported so far about the shaft torsional oscillations of synchronous generators. Though a large number of wind generators are going to be connected with the existing network, the blade-shaft torsional oscillations of WTGS have not been reported so far sufficiently. In this paper, damping control of blade-shaft torsional oscillations of WTGS by using a voltage source converter (VSC) based STATCOM/BESS (battery energy storage system) topology is proposed. The six-mass drive train model of WTGS is used in the simulation analyses for the sake of precise analysis. Both symmetrical and unsymmetrical faults are considered as a network disturbance in the analyses. Simulation results clearly show that the proposed STATCOM/BESS can significantly decrease the blade and shaft torsional oscillations of WTGS. The simulations have been done by PSCAD/EMTDC.