Analysis of Grid-connected Stability of Voltage-source-type PMSG-based Wind Turbine Based on Virtual Synchronous Control

Abstract

With the increase of wind turbines, the stable operation of wind turbine under weak grid is facing challenges. The voltage-source-type wind turbine is more suitable for weak grid because it is not affected by phase-locked loop and can provide frequency and voltage support. In order to study the grid-connected stability of voltage-source-type permanent magnet synchronous generator (PMSG), the model of system is established. Then, the grid-connected stability of current/voltage-source-type PMSG are compared through eigenvalue analysis. It is found that voltage-source-type PMSG is more adaptable to weak grid but prone to low-frequency oscillation at high short circuit ratio (SCR). And the influence of key parameters is studied. Then, the grid-connected stability of the current/voltage-source-type PMSG hybrid wind farm is studied. It is found that voltage-source-type PMSG can improve the stability of wind farm under weak grid. Finally, the electromagnetic transient simulations verify the eigenvalue analysis results.