• Journal of Institute of Control, Robotics and Systems
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• v.6 no.3
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• pp.284-290
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• 2000

The measurement of electric current using optical techniques provides a number of important practical advantages including effective isolation from high line potentials and freedom from the saturation effects observed in conventional current transformers. In this work the optical current sensor which uses thin YIG(Yittrium Ion Garnet) film as a Faraday element has been developed. We have characterized this optical current sensor and implemented it to the OOCR(Opto-electronic OverCurrent Realy) Performance of the OOCR shows the possibility of replacing the present overcurrent relays with OOCR.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1846-1849
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• 1998

An optical magnetic filed sensor, YIG (Yittrium Iron Garnet), response rapidly, to the power-line currents to be measured. In response to Faraday effect, it shows wide-and-linear measurable range. This paper reports the development and implementation of an OOCR (Optoelectric OverCurrent Relay) using this sensor. This relay is free from environmental electro-magnetic noises and has excellent insulation characteristics inherently. By using this OOCR, we can reduce insulation cost of protective relaying systems and its maintenance cost, and can achieve high reliability of the system.

• Journal of the Korean Chemical Society
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• v.17 no.2
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• pp.115-121
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• 1973

Crystalline products were obtained when$TiCl_4$ was reacted in dichloromethane with acetic, propionic, crotonic, benzoic, furoic and salicylic acids. Chemical analysis has shown that these were all dichlorodicarboxylatotitanium (IV). Cryoscopy of dichlorodipropionatotitanium (IV) indicated the carboxylato-complexes are dimeric. In the IR spectra of these complexes two strong bands both assigned to asymmetric carbonyl stretching vibration have been observed in the region$1500 - 1700cm^{-1}$ and the NMR spectrum of dichlorodipropionatotitanium (IV) has also shown two triplets and two quartets, which indicate that there are two chemically unequivalent carboxylato-ligands in the dimer $[TiCl_2(OOCR)_2]_2$. Their molecular structure was proposed to be bis-carboxo-bridged dimer.