A pre-estimation filtering process of bad data for linear power systems state estimators using PMUs

Abstract

Abstract-The paper proposes a specific algorithm for the pre-estimation filtering of bad data (BD) in PMU-based power systems linear State Estimators (SEs). The approach is framed in the context of the so-called real-time SEs that take advantage of the high measurement frame rate made available by PMUs (i.e., 50 -60 frames per second). In particular, the proposed algorithm examines PMU measurement innovations for each new received set of data in order to locate anomalies and apply countermeasures. The detection and identification scheme is based on: (i) the forecasted state of the network obtained by means of a linear Kalman filter, (ii) the current network topology, (iii) the accuracy of the measurement devices and (iv) their location. The incoming measurement from each PMU is considered reliable, or not, according to a dynamic threshold defined as a function of the confidence of the predicted state estimated by using an AutoRegressive Integrated Moving Average (ARIMA) process. The performances of the proposed algorithm are validated with respect to single and multiple bad data of different nature and magnitudes. Furthermore, the algorithm is also tested against faults occurring in the power system to show its robustness during these unexpected operating conditions.

Fault Detection and Faulted Line Identification in Active Distribution Networks Using Synchrophasors-Based Real-Time State Estimation

“…It is worth observing that the current literature has shown a growing interest in PMU deployment and their applications in distribution systems: recent publications have illustrated and discussed distribution networks equipped with PMUs in every bus [9], [21]. 4) Due to the stringent time requirements of the targeted application, bad data are removed from the measurement set by using the pre-filtering algorithm described in [22] that was proved to be robust against faults.…”

Architecture and experimental validation of a low-latency phasor data concentrator

“…In such a case, the subsequent applications are assumed to cope with incomplete datasets by using replacement techniques or historical information (e.g. [20], [21]). Consequently, a delayed packet that reaches the PDC when its corresponding dataset has already been pushed, is lost and it is no longer available for further applications.…”

GridBox pilot project

“…The elementary real-time application consists of a linear three-phase state estimator based on concepts presented in [8,9] capable of detecting and treating bad data such as measurement deviations and of handling missing data. Missing Besides technical reasons such as inaccessible cable junctions in the ground, it is also an economical motivation to deploy only as many GridBoxes as necessary.…”