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Dr. Ali Abur gave two seminars at University of Seville, Spain last week. Each seminar was attended by approximately 20-25 participants consisting of faculty, graduate students and researchers. The seminars were also broadcasted live to two other institutions in Spain.  

The first seminar was on May 28th and was titled "Linear State Estimation of Balanced and Unbalanced Systems. " The second seminar was on May 29th and was titled "Detection of System Disturbances Using Sparsely Placed Phasor Measurements."

Abstract: Linear State Estimation of Balanced and Unbalanced Systems - Exclusive use of phasor measurements provided by phasor measurement units (PMU) for static state estimation allows implementation of simplified and robust solution algorithms. In this talk we will first review the state estimation prob-lem formulation based on conventional measurements and then show the bene-fits of using PMU measurements. Two alternative solution algorithms will then be presented. These algorithms will be shown to possess some attractive fea-tures with respect to computational effi-ciency as well as robustness against bad data. In addition, side benefits that im-pact capability to detect and identify parameter errors as a result of using PMU measurements will also be de-scribed. In addition to the conventional balanced system solution, it will be shown that unbalanced operation can also be monitored using similar algo-rithms with minimal changes made in the balanced algorithm. Numerical examples will be used to illus-trate the discussed procedures and solu-tions when applied to typical power sys-tems.

Abstract: Detection of System Disturbances Using Sparsely Placed Phasor Measurements - This talk will cover some applications of sparse estimation methods to power sys-tem problems. The common enabling technology for these applications will be the phasor measurement units which can provide voltage and current phasor meas-urements at sampling rates of 30 times a second. We will first review the main fea-tures of these devices and then describe two power system problems which can be formulated in such a way that their solu-tion can be obtained using phasor meas-urements and sparse estimation methods. The first application is the identification of branch outages for grids which are not fully observable. One example is the identification of outages in external sys-tems from which a very limited number of real-time measurements are typi-cally available. The problem of line outage identification will be formu-lated as a sparse selection problem and will be solved by a mixed integer programming algorithm. The second example is related to fault location in power grids where synchronized voltage measurements are sparsely available at a limited number of bus-es. It will be shown that the fault location problem can be formulated as a sparse regression problem and then solved using the least absolute selection and shrinkage operator (lasso) algorithm. Relationship be-tween the equivalent current injec-tions at faulted branch terminals and the distance to the fault point along the branch yields a fast and efficient way to locate faults.

Ali-Abur-NEU.pngBio: Dr. Ali Abur obtained his B.S. degree from Orta Do?u Teknik Üniversitesi, Ankara, Turkey in 1979 and M.S. and Ph.D. degrees from The Ohio State University in 1981 and 1985, respectively. He was a faculty member at Texas A&M University until November 2005 when he joined the faculty of Northeastern University. He served as Chair of the Electrical and Computer Engineering Department at Northeastern until 2013. He is currently a Professor in the same department with research and educational activities mainly in the area of power systems. He is an IEEE PES Distinguished Lecturer and a Fellow of the IEEE for his work on power system state estimation. He has co-authored a book and published widely in IEEE journals and conferences. He was on the Editorial Board of IEEE Transactions on Power Systems and Power Engineering Letters during 1999-2011.