Examining characteristics of an observability formulation for nonlinear power systems

The concept of developing a technique to evaluate the observability of nonlinear systems in general, and its specific application to nonlinear power systems has been introduced in the past. This technique allows for the evaluation of system observability along the trajectories of the system dynamic states, providing the ability to trick the system through various perturbations. This paper focuses on qualifying the implications associated with the evaluation of the observability Jacobian due to the presence of dynamic loads (exponential recovery model) and varying the system/measurement differentiation indices for a given measurement set. These conditions are illustrated with a qualitative analysis of a 3-bus power system.