Based on the finite element method to establish the model, we can analysize the safety time impacted by wind speed, direction angle, capacity, environmental temperature and sunshine intensity. With the increase of wind speed, it will sharply reduce the time to steady state. Since we give them the same change, the wind speed is smaller and the change is bigger; With the increase of wind angle, it needs less time to steady state. When the angle is more than 60 °, it almost has no influence on the time. If load flow changes, there is a huge change about the safety time. Environment temperature and sunshine intensity have little influence.