Distance Relay Co-ordination Using Support Vector Machines in Power Transmission System

In this paper, a new approach to enhance the transmission system distance relay co-ordination is presented. The approach depends on the apparent impedance loci seen by the distance relay during all possible disturbances. In a distance relay, the impedance loci seen at the relay location is obtained by extensive transient stability studies. Support vector machines (SVMs), a class of patterns classifiers are used in discriminating zone settings (zone-1, zone-2 and zone-3) using the signals to be used by the relay. Studies on a sample 9-bus are presented for illustrating the proposed scheme.

Crystal co-ordination of the barium ion

A systematic study has been made of the crystal co-ordination of the barium ion in various compounds whose structures have been solved. Apart from the more common co-ordination polyhedra which are enumerated in text-books, a number of new polyhedra have been identified, particularly in cases where the co-ordination numbers are unusual, such as ten or eleven. According to the radius-ratio rule of Pauling, a co-ordination number of nine or ten is normally expected for the barium ion. The present investigations, however, reveal that it shows a variety of co-ordinations with ligancies from six up to twelve. Some of the factors that might possibly enter in explaining this wide range of co-ordination numbers are discussed. It appears as though the part played by the Ba2+ ion in deciding the structure is secondary, limiting itself only to occupying vacant spaces provided by other atoms in the crystal.

Three different co-ordination geometries in the pentacopper(II) unit of [Cu5(OH)2(H2O)(O2CMe)6(Him)4][ClO4]2(Him = imidazole)

The reaction of imidazole (Him) with [Cu2(µ-O2CMe)4(H2O)2] in water–NaClO4 led to the formation of a polynuclear copper(II) complex, [Cu5(OH)2(H2O)(O2CMe)6(Him)4][ClO4]21, in which the pentanuclear units, showing four, five and six co-ordination geometries for the copper(II) centres and Cu Cu distances of 3.043(1), 3.178(1) and 3.578(1)Å, were linked by aqua bridges to give an intra-chain inter-unit Cu Cu separation of 4.507(1)Å.

An unusual axial co-ordination of phenolate oxygen to copper(II): crystal structure of chloro(2-[bis(2-pyridylmethyl)aminomethyl]-4-nitrophenolato)copper(II)

A tripod ligand possessing two pyridine moieties and a phenolato group as pendants forms a mononuclear complex with an axial copper(II)–phenolate co-ordination in a square-pyramidal environment.

A porphyrin bearing tetrahydrothiophene pickets; co-ordination behaviour and electron transfer

A novel ‘picket-fence’ porphyrin, 5,10,15,20-tetrakis[o-(tetrahydro-2-thenoylamino)phenyl]porphyrin (H2L) with ligating tetrahydrothiophene rings disposed perpendicular to the porphyrin plane has been synthesised. Its zinc(II) derivative, [ZnL], binds two silver(I) ions co-operatively with a dissociation constant of 4.8 × 10–8 dm3 mol–1. Time-resolved fluorescence lifetime measurements reveal the presence of intramolecular photoexcited electron transfer in this donor–acceptor system.

An Approach for Distance Relay Co-ordination using Support Vector Machines

In this paper, an approach to enhance the Extra High Voltage (EHV) Transmission system distance protection is presented. The scheme depends on the apparent impedance seen by the distance relay during the disturbance. In a distance relay,the impedance seen at the relay location is calculated from the fundamental frequency component of the voltage and current signals. Support Vector Machines (SVMs) are a new learning-byexample are employed in discriminating zone settings (Zone-1,Zone-2 and Zone-3) using the signals to be used by the relay.Studies on 265-bus system, an equivalent of practical Indian Western grid are presented for illustrating the proposed scheme.

Knowledge-Based Approach Using Support Vector Machine for Transmission Line Distance Relay Co-ordination

In this paper, knowledge-based approach using Support Vector Machines (SVMs) are used for estimating the coordinated zonal settings of a distance relay. The approach depends on the detailed simulation studies of apparent impedance loci as seen by distance relay during disturbance, considering various operating conditions including fault resistance. In a distance relay, the impedance loci given at the relay location is obtained from extensive transient stability studies. SVMs are used as a pattern classifier for obtaining distance relay co-ordination. The scheme utilizes the apparent impedance values observed during a fault as inputs. An improved performance with the use of SVMs, keeping the reach when faced with different fault conditions as well as system power flow changes, are illustrated with an equivalent 265 bus system of a practical Indian Western Grid.

Simultaneous co-ordination of three cytosine ligands displaying different binding sites around the copper centres

We report the synthesis and structural characterization of a polymeric ternary copper-cytosine-phenanthroline complex, Cu-4(phen)(3)-(mu(3)-cyt)(2)(mu-OH)(cyt)(OH)Cl-3](n)center dot 16H(2)O, where three cytosine ligands with different binding sites have simultaneously complexed to the four copper metal centres. Interestingly, the complex exhibits two different coordination geometries around the metal centres.