An improved initial guess of Newton method for hybrid state estimation

The hybrid state estimation of a power system, where the measured data consist of both conventional measurements and synchronizing phasor measurements, is generally formulated as a nonlinear optimization problem. It is then solved by Newton based iteration procedure whose success depends on an appropriate initial guess. This paper presents an improved method for selecting a suitable initial solution for this problem. All data obtained from both conventional and synchronizing phasor measurements are employed to estimate the initial guess. Numerical results on the IEEE 14-bus and 57-bus systems indicate that the proposed technique provides better convergence performance than the method previously proposed in Ref. [5].