Physically-based aggregation of object-oriented load models in power systems restoration

The restoration process after a partial or total blackout is a very peculiar situation in terms of load modeling, since the nodal load can assume a different behavior from the expected load under normal operation conditions. Thus, particularly in this case, it is important to develop accurate load models to avoid mistakes during the reenergization process. This work proposes the usage of object-oriented and hybrid load models to represent the aggregated load of a distribution feeder or substation. Besides, a physically-based load aggregation methodology is formulated, taking into account the physical characteristics of the individual equipments, both electrical and environmental, and power line losses evaluation through the application of one single iteration of the back-forward sweep distribution load flow method. A study case and results comparing the conventional and the proposed approach are presented.