Numerical observability analysis based on network graph theory

Korres, GN; Katsikas, PJ; Clements, KA; Davis, PW

dc.contributor.author	Korres, GN	en
dc.contributor.author	Katsikas, PJ	en
dc.contributor.author	Clements, KA	en
dc.contributor.author	Davis, PW	en
dc.date.accessioned	2014-03-01T01:19:20Z
dc.date.available	2014-03-01T01:19:20Z
dc.date.issued	2003	en
dc.identifier.issn	0885-8950	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/15436
dc.subject	Echelon forms	en
dc.subject	Graph theory	en
dc.subject	Incidence matrix	en
dc.subject	Loop-to-branch matrix	en
dc.subject	Maximal observable islands	en
dc.subject	Observability analysis	en
dc.subject	Rank deficiency	en
dc.subject.classification	Engineering, Electrical & Electronic	en
dc.subject.other	Algorithms	en
dc.subject.other	Graph theory	en
dc.subject.other	Iterative methods	en
dc.subject.other	Matrix algebra	en
dc.subject.other	Topology	en
dc.subject.other	Gain matrix	en
dc.subject.other	Electric power systems	en
dc.title	Numerical observability analysis based on network graph theory	en
heal.type	journalArticle	en
heal.identifier.primary	10.1109/TPWRS.2003.814882	en
heal.identifier.secondary	http://dx.doi.org/10.1109/TPWRS.2003.814882	en
heal.language	English	en
heal.publicationDate	2003	en
heal.abstract	This paper presents a numerical method for topological observability analysis of a measured power system. By floating-point operations on the echelon form of a rectangular test matrix, which is based on network graph properties, observability and maximal observable islands are determined. A minimal set of pseudo measurements, which make an unobservable network barely observable, is selected in a noniterative manner. The existing numerical methods are based on the number of zero pivots that may appear during the factorization of the measurement Jacobian or the gain matrix. Due to round-off errors, the zero pivots may be misclassified. The problem becomes more severe when the number of injection measurements is large, resulting in a great disparity of values in Jacobian or gain matrix. In the proposed method, the test matrix consists of + / - 1 values, it is numerically better conditioned and zero pivots are identified more accurately. By topological processing of the flow measured branches and by removing the redundant injection measured nodes that are incident only to flow measured branches or branches which form loops with flow measured branches, a reduced test matrix is created with fewer nonzero. elements than the Jacobian or the gain matrix, resulting in less computational effort. The method details are illustrated by various test systems.	en
heal.publisher	IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC	en
heal.journalName	IEEE Transactions on Power Systems	en
dc.identifier.doi	10.1109/TPWRS.2003.814882	en
dc.identifier.isi	ISI:000184455100009	en
dc.identifier.volume	18	en
dc.identifier.issue	3	en
dc.identifier.spage	1035	en
dc.identifier.epage	1045	en