Due to expansion of power network, the short circuit current of power system are increased. Fault current limiters (FCL) are responsible to reduce and limit the fault currents. In addition, these components can also improve the stability of system. In this paper the effect of type and amount of FCL impedance on angle stability power system is investigated. Furthermore, the indices of rotor mechanical angle generator, when it reaches the steady state, after oscillations due to the fault occurrence for two types of FCL impedance (resistant and inductance) are being studied. Based on these indices, the amount of optimum FCL impedance for both resistant and inductance FCL are simulated and calculated on a tested network using a developed computer program. پرونده مقاله