Large number of wind turbines are being installed

and connected to power systems. The penetration level of wind

power is continuously increasing in some networks, the

significant high penetration may affect the power system security

if the wind generators can not recover to normal operation

immediately after a temporary disturbance. This paper studies

the effect of power electronic system on stability improvement of

a wind turbine system. The functions of the STATCOM and

DVR in improving the system stability have been demonstrated.-Large number of wind turbines are being installed

and connected to power systems. The penetration level of wind

power is continuously increasing　in some networks, the

significant high penetration may affect the power system security

if the wind generators can not recover to normal operation

immediately after a temporary disturbance. This paper studies

the effect of power electronic system on stability improvement of

a wind turbine system. The functions of the STATCOM and

DVR in improving the system stability have been demonstrated.