Enhanced Linear State Estimation for Power Systems Using Purely SCADA Measurements

Linear state estimation (LSE) has long been sought after because of its simplicity, practicality, efficacy and computational speed. This paper presents an enhanced linear state estimation (ELSE) for power systems using purely time-non-synchronized SCADA measurements. In order to be able to derive current and voltage phasors from SCADA measurements, voltage phase angles are incorporated into the model formulation as pseudo-measurements. These pseudo-measurements can be obtained using either historical data or an analytical method based on an existing LSE. The proposed formulation can be readily solved by the weighted least squares (WLS) method. The accuracy and computational efficiency of the proposed ELSE, compared to the existing state estimation methods, are evaluated and demonstrated for several test systems.