Abstract:

Using singular perturbation model,by the example of a simple power system losing stability in big disturbance, this paper analyses the mid-long term instability mechanisms affected by slow dynamics. It points out that fixing slow dynamics randomly in building model may cause incorrect estimation of mid-long term stability. These results are both theoretically and practically significant in the study of mid-long term stability of power system.

Key words: mid-long termstability, stability mech anisms, slow dynamics, singularpermrbation