Load modeling for fault location in distribution systems with distributed generation

This paper shows the influence of the load modeling in the behavior of voltage (V), current (I) and impedance (Z) measurements during pre-fault and fault steady states of power distribution systems. The test system is the 24.9 kV IEEE 34 nodes power distribution system, modeled by ATP software, considering load models as constant impedance, constant current, constant power and hybrid load composed using the previous three models. All loads were coded using Models of ATP. As result of the test, a comparative analysis of the signals of V and I measurements and also Z as seen from the power substation is performed. The result shows that the load model affects the fault steady state of the power distribution system, which directly will influence the fault locator performance, since this uses the measurements of V and I at the power substation at pre-fault and fault steady states.