Determination of ZIP parameters with least squares optimization method

An appropriate operation of a power system in steady state situation and the equal values of bus voltages and the nominal ones, depends on the probable changes in the load, so the exact description of the load is very important, on the other hand the load characteristics have a significant effect on the performance of a power system. Until now the constant representation of the loads was assumed in load flow programs and equations. Because of changing in power, current and impedance of the load of the power system along the day, the constant power model for the power system can not be correct. This paper presents the algorithm of least squares to determine the parameters of “ZIP” load model. This algorithm is tested on a 2 bus test system to show the applicability of this method. It is noted that this method is a measurement based approach.