A Two-Level Static State Estimator for Electric Power Systems

Generalized State Estimation of Flexible AC Power Systems Considering Wind Generators and Primary Frequency Control

“…Since the variables s and R ext are directly correlated by one single equation, the total resistance R X of the rotor circuit has been considered to be the WTG's state variable to be estimated. Based on the information mentioned above, the active and reactive powers at the generator's terminals are given by (13) and (14) [9], while the current phasor in rectangular components is given by (15) and (16) …”

“…Monitoring large-scale power systems comprising multiple control areas, however, requires an enormous computational burden since the sets of measurements to be processed and state variables to be estimated become extremely large. An approach for alleviating this problem was proposed in [16] as early as 1981 and consisted of decentralizing the estimation in two stages: the power system under study was first decomposed into several control areas, and their corresponding local operation states were estimated; these local estimations were then gathered to generate a single coordinated state estimation for the entire power grid. By following this line of reasoning, several decentralized multi-area state estimators (MASEs) have been proposed, according to [17] and the references therein, to reduce the amount of memory requirements and computation time.…”

Convergence and Applications of a Gossip-Based Gauss-Newton Algorithm

“…Lemma 4: Let the minimum exchange be chosen based on an arbitrary value using (45). According to Lemma 1 under Assumption 1, 2, 3 and 4, then if the initializer is the same for all agents , the deviation for any and at the -th update satisfies (48) where is the gossip error scale in (39), are defined in (47) and…”

“…From (43) and (103), we have (106) (107) where the last inequality comes from the non-negativity of (i.e., for all finite ). By the definition of in (45) in Assumption 4, we have (108) where we have used the fact that (see (91)). Therefore, the matrix series expansion holds for (105).…”

An optimal hierarchical algorithm for factored nonlinear weighted least squares state estimation

“…These requirements are unlikely to be met and more efficient local information processing methods are needed. Distributed multi-area state estimation methods have been considered to overcome these issues [1]- [7].…”