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Volume 5, Issue 1 2006 Article 8 International Journal of Emerging Electric Power Systems Non-Contact Determination of the Phase Sequence and Voltage Level of Overhead Conductors in Air Insulated Substations Fei Li, University of Strathclyde Philip J. Moore, University of Strathclyde Recommended Citation: Li, Fei and Moore, Philip J. (2006) "Non-Contact Determination of the Phase Sequence and Voltage Level of Overhead Conductors in Air Insulated Substations," International Journal of Emerging Electric Power Systems: Vol. 5: Iss. 1, Article 8. DOI: 10

Abstract

The present paper shows the simulation results of turbogenerator faulty synchronization with inverse phase sequence. Great emphasis is placed on the physical phenomena existing in the rotor because the measurement of rotor damper bar currents is difficult in practice. There are presented the comparisons of maximum magnitudes of stator current and electromagnetic torque determined during faulty synchronization with maximum magnitudes designated during sudden short circuit after both no-load and rated operation condition. In addition, the effect of synchronizing limits on faulty synchronization is presented.

4(4-Alkyloxybenzoyloxy)-4' -cyanoazobenzole: Eine homologe Reihe flüssigkristalliner Verbindungen mit der ungewöhnlichen Phasenfolge smektisch A-nematisch-smektisch A 4(4-Alkyloxybenzoyloxy)-4'-cyanoazobenzenes: A Homologous Series of Liquid Crystals Exhibiting the Unusual Phase Sequence Smectic A - Nematic - Smectic A Gerd Heppke*, Reinhard Hopf, Bernd Kohne und Klaus Praefcke* [1] Fachbereich für Synthetische und Analytische Chemie der Technischen Universität Berlin, Straße des 17. Juni 135, D-1000 Berlin 12 Z. Naturforsch. 35b, 1384-1388 (1980

Abstract

Phase diagrams at 298.2 K were determined for aqueous systems of alkylamines and alkanoic acids in equimolecular ratio, i.e. for alkylammonium alkanoates. The bilayer structural evolution for these ionic surfactants with organic counter-ions in water was studied using transmission electron microscopy (TEM), optical microscopy, small-angle X-ray scattering (SAXS) and rheological measurements. The formed vesicles are highly viscoelastic and have a yield stress value. In the pentylammonium nonanoate-water system at higher contents, the vesicles collapse to micelles, while in the hexylammonium nonanoate-water and in the pentylammonium decanoate systems, a transition to a fully expressed lamellar phase is observed. The results are discussed in terms of electrostatic interactions and membrane flexibility.

–0097 $ 06.00 c© 2004 Verlag der Zeitschrift für Naturforschung, Tübingen · http://znaturforsch.com per hour. The polarized thermal microscopic textural observations (focal conic batonnet texture in SmA and threaded marble schlieren in SmC*) suggested [7] the following phase sequence: Crystal −17.0 ◦C−−−−−→ SmC∗ ←96.5 ◦C−−−−→ SmA←119.3 ◦C−−−−−→ Isotropic. 98 A. K. George et al. · Studies on Room Temperature Ferroelectric Liquid Crystal, 12CN5(R∗) Fig. 1. Temperature variation of the spontaneous polarization PS(T ). Solid line represents data fitted to (1). The compound

controller of thyristor rectifier for high voltage formed aluminium foil based on TMS320F2812. The hard- ware and software design of the controller is investigated in details. This paper pre- sented a grid frequency tracking and phase sequence adaptive method and steps. Experimental results show that the trigger controller has good performance due to simple hardware, high reliability. Keywords: Phased rectifier; Phase sequence adaptive; Digital signal processor 1 Introduction A thyristor rectifier and its controller are key equipment of high voltage formed

Direct Determination of the Anisotropy of the Magnetic Susceptibility in Smectic Liquid Crystals G. Illian, H. Kneppe. and F. Schneider Physikalische Chemie, Universität Siegen Z. Naturforsch. 40a ,46-51 (1985); received September 29. 1984 A sample of an aligned smectic liquid crystal, suspended in a magnetic field, can be excited to oscillations. Measurement of the oscillation period allows a direct determination of the aniso- tropy of the magnetic susceptibility. Liquid crystals exhibiting the phase sequence isotropic- nematic-smectic A can be aligned

_{\boldsymbol{x}}=\sum_{k=0}^{L-1}\, |x_k|^2 \end{array}$ the energy of the sequence and δ a, b the Kronecker’s delta. When the sequence is composed of phases, | x k | = 1, it is said unimodular or of constant amplitude (CA). Accordingly, phase sequences which are also perfect are said CAZAC sequences. Their basic characterization follows from the (unitary) Discrete Fourier Transform (DFT) of the autocorrelation, 1 L ∑ n = 0 L − 1 R x ( n ) e − j 2 π n m / L = L | X m | 2 , $$\begin{array}{} \displaystyle \frac{1}{\sqrt{L}} \sum_{n=0}^{L-1}R_{\boldsymbol{x}}(n) e^{-j2\pi nm

Polymorphism and multiple twinning of (Et4N)2ZnCl4 P. Sondergeld*, I, II, H. FuessII, H. IshiharaIII and W. W. SchmahlIV I University of Wien, Institut für Experimentalphysik, Strudlhofgasse 4, A-1090 Wien, Austria II University of Technology, Institute for Materials Science, Darmstadt, Germany III Saga University, Faculty of Education, Japan IV Ruhr-Universität Bochum, Institut für Mineralogie, Germany Received August 18, 2000; accepted February 23, 2001 Abstract. The phase sequence of (Et4N)2ZnCl4 has been determined based on thermal analysis and 35Cl NQR

Reprint requests to Prof. S. U.; Fax: 048-12-6337086. E-mail: ufurban@cyf-kr.edu.pl Z. Naturforsch. 58a, 333 – 340 (2003); received February 17, 2003 For the first time the low frequency relaxation process in two smectic phases (smectic A and smec- tic C) was studied at elevated pressures with the aid of DTA and dielectric spectroscopy. The sub- stance studied, 2-(4-hexyloxyphenyl)-5-octyl-pyrimidine (6OPB8 in short) exhibits the nematic (N) – SA – SC phase sequence. The p-T phase diagram was established with DTA. However, the SA – SC transition was not observed in the