Effects of load modeling on minimum loss, minimum emission, and multiple-objective optimal hydrothermal power flow

The effects of incorporating load models in three formulations of hydrothermal optimal power flow are considered in this paper. The formulations are transmission loss minimization, NOx minimization, and the multiple objectives of minimum NOx emission and minimum cost. The conventional algorithms and those incorporating load models were tested using a 14-bus and a 30-bus test system. Solutions are obtained using the MINOS optimization package. The computation time requirements of the conventional algorithm are lower than those incorporating load models. In all cases, there are measurable differences in the optimal voltage magnitudes for the systems tested. Incorporating load models yields lower active power generations and transmission losses, lower thermal fuel costs and reduced environmental impact than the conventional formulations.