A novel methodology for power angle estimation of synchronous generator based on trajectory sensitivity analysis

This paper proposes a new indirect approach to estimate the power angle of synchronous generators from three-phase currents and voltages, and field voltage measurements. An auxiliary algebraic equation, which relates the power angle with generator parameters and measurements, is included in the generator model. Therefore, the generator is modeled by a set of differential-algebraic equations (DAEs). The procedure is split into two steps. In the first step, uncertain parameters and the power angle are estimated simultaneously using an estimation methodology based on trajectory sensitivity analysis. In the second step, the load angle is estimated directly from the DAEs of the generator model by an implicit integration method. The power angle was correctly estimated even with noise in all the measurements and uncertainties in all the generator parameters.