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The complex [(tpy)Ru(tpp)RhCl(3)](PF(6))(2) (tpy = 2,2',6',2"-terpyridine and tpp = 2,3,5,6-tetrakis(2-pyridyl)pyrazine) has been prepared and its spectroscopic, electrochemical, and photophysical properties investigated. This complex couples a ruthenium light absorber to a rhodium electron acceptor to create the first tpp-bridged light-absorber-electron-acceptor dyad. This study illustrates the applicability of this (tpy)Ru(II)(&mgr;-tpp) chromophore in the construction of photochemical molecular devices. This system is of interest since the tpp ligand has been shown to provide stereochemically defined polymetallic complexes with reasonably long-lived metal to ligand charge transfer excited states. The complex [(tpy)Ru(tpp)RhCl(3)](PF(6))(2) displays a Ru-->tpp CT transition centered at 516 nm that is the lowest lying electronic transition. The electrochemistry of [(tpy)Ru(tpp)RhCl(3)](PF(6))(2) shows a Ru(II/III) couple at 1.60 V vs Ag/AgCl, an irreversible Rh(III/I) reduction at -0.23 V and, a tpp(0/)(-) couple at -0.60 V. This illustrates that although this complex has a lowest lying spin-allowed spectroscopic transition that is Ru-->tpp CT in nature, the lowest occupied molecular orbital is Rh based. Thus, following excitation of this [(tpy)Ru(tpp)RhCl(3)](PF(6))(2) complex into the Ru-->tpp CT state, electron transfer to the rhodium is thermodyamically favorable. This electron transfer leads to a quenching of the emission normally observed for this Ru-->tpp CT excited state. Emission quenching for [(tpy)Ru(tpp)RhCl(3)](PF(6))(2) via electron transfer is 80% efficient with a k(et) of 4 x 10(7) s(-)(1). Details of these studies are presented herein.

The aim of this paper is to present methods on realtime event detection and data archival reduction based on synchrophasor data produced by phasor measurement unit (PMU). Event detection is performed with principal component analysis and a second order difference method with a hierarchical framework for the event notification strategy on a small-scale microgrid. Compared with the existing methods, the proposed method is more practical and efficient in the combined use of event detection and data archival reduction. The proposed method on data reduction, which is an "event oriented autoadjustable sliding window method," implements a curve fitting algorithm with a weighted exponential function-based variable sliding window accommodating different event types. It works efficiently with minimal loss in data information especially around detected events. The performance of the proposed method is shown on actual PMU data from the Illinois Institute of Technology campus microgrid, thus successfully improving the situational awareness of the campus power system network.Index Terms-Archiving, event detection, phasor measurement unit (PMU), principal component analysis (PCA), reduction, situational awareness (SA), synchrophasor.

International Electronical Committee (IEC) 61850-90-7 is a part of the IEC 61850 series which specifies the advanced functions and object models for power converter based Distributed Energy Resources (DERs). One of its functions, the Voltage/VAR (V/V) control function, is used to enhance the stability and the reliability of the voltage in the distribution system. The conventional V/V function acts mainly for flattening the voltage profile as for a basic grid support function. Currently, other objectives such as the minimization of line loss and the operational costs reduction are coming into the spotlight. In order to attain these objectives, the V/V function and hence the DER units shall actively respond to the change of distribution system conditions. In this paper, the modification of V/V function and new requirements are proposed. To derive new requirements of V/V function, loss minimization is applied to a particle swarm optimization (PSO) algorithm where the condition of voltage constraint is considered not to deteriorate the voltage stability of the distribution system.

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