Modeling, analysis, and measurement of impedance for three-phase AC distributed power system

Before the stability analysis for AC distributed power system by using impedance based criterion, the impedance matrix of system must be captured exactly. The output impedance model of inverter is developed in this paper. The relationship between the impedance and the parameters of system is discussed. Disturbed current injection based, an impedance measurement unit is implemented. By injecting disturbed current two times, the impedance matrixes for a practical three-phase AC distributed system can be calculated. Experimental results demonstrate the effectiveness of the proposed method.