Tracking network state from combined SCADA and synchronized phasor measurements

Initiated by the authors´ previous work on state reconstruction from a limited number of synchrophasors [1], this paper goes one step further by exploring the possibility to track the network state using both SCADA and synchronized phasor measurements. When a SCADA measurement is received, it is used in the next state reconstruction; otherwise, it is replaced by a pseudo-measurement stemming from the previous state reconstruction. The approach resorts to a standard weighted least squares formulation and Hachtel´s augmented matrix method. State reconstruction is intended to be used at a much higher rate than classical state estimation, for instance every second. It has been validated using simulated measurements obtained from detailed time simulation.