Reclosure of circuit breakers following a fault on a high-voltage transmission line with a minimum of delay in order that synchronous load will not fall out of step is described in this paper. Apparatus that performs ...
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This paper represents the first of a series of studies on the physical and mathematical analysis of the steady-state stability of conventional and long-distance transmission systems as influenced by the presence of vo...
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This paper represents the first of a series of studies on the physical and mathematical analysis of the steady-state stability of conventional and long-distance transmission systems as influenced by the presence of voltage regulators and other control devices. As a first step attention is restricted to the transmission line as a component part of the over-all system and practical equivalent circuits are established for its representation, when the connected synchronous machines oscillate. For that purpose the basic equations of stationary networks are set up when viewed from uniformly rotating reference frames. An isolated inductor and capacitor, then a transformer, and finally a transmission line are used as examples. Their equations viewed from a simultaneously rotating and oscillating reference frame are given in reference 1. COPYRIGHT 1949 BY THE AMERICAN INSTITUTE OF ELECTRICAL ENGINEERS
The majority of water-wheel generators now in service have been built without damper windings. Recent technical investigations and laboratory tests have indicated that, in addition to reducing oscillations and improvi...
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This paper deals with shaping the output pulse of a line-type pulser by means of tapering the distributed elements (L and C) of the line and, secondly, with calculating pulse shape for a given taper. It proves possibl...
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This paper deals with shaping the output pulse of a line-type pulser by means of tapering the distributed elements (L and C) of the line and, secondly, with calculating pulse shape for a given taper. It proves possible to generate perfectly flat pulses on a conventional load (resistance and inductance in parallel) by appropriate line tapering. Also related problems can be solved with exactness. Calculation of pulse shape resulting from a given taper is more difficult. Here only approximations have been obtained. The mathematical method used consists essentially in expressing line voltage and current as Maclaurin series in which the relations existing at load and at front are introduced. This leads to exact or approximate solutions of the problem.
Summary form only. An abstract of the above-titled article, taken from the 1963 IEEE International Convention (held March 25-28, New York, NY, USA), is presented.
Summary form only. An abstract of the above-titled article, taken from the 1963 IEEE International Convention (held March 25-28, New York, NY, USA), is presented.
A schematic diagram of the constant phase difference circuits to be discussed is given in Fig. 1. It consists of two similar two-port log-periodic circuits with their inputs connected in parallel.
A schematic diagram of the constant phase difference circuits to be discussed is given in Fig. 1. It consists of two similar two-port log-periodic circuits with their inputs connected in parallel.
The theoretical problem of a bend on a two-wire transmission line is analyzed by the vector-potential method. The equivalent circuit elements are obtained by comparing the variableline parameters near the bend with th...
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The theoretical problem of a bend on a two-wire transmission line is analyzed by the vector-potential method. The equivalent circuit elements are obtained by comparing the variableline parameters near the bend with the conventional line parameters found on an infinite line. The effect of the nonrotational symmetry of the axial vector potential on the conductor surfaces is treated by an approximate method to obtain one of the equivalent series elements. Experimental values of the circuit elements for the bend were found to be in good agreement with the theoretical. Good agreement was also found between experimental and theoretical values for open-ended and bridged-end lines.
The “Linascope,” an electronic fault locator is described which uses an echo-ranging method for determining the location and nature of transmission line faults. This device has been used on open-wire telephone circu...
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The “Linascope,” an electronic fault locator is described which uses an echo-ranging method for determining the location and nature of transmission line faults. This device has been used on open-wire telephone circuits for the location of various fault conditions, including open and short circuits, and high-resistance joints. Tests have been performed on high-voltage transmission lines which were removed from service for the purpose. Artificial faults applied at distances as great as 300 miles were detected. Open and short circuit faults are readily observed. Transposition points give slight echoes. The equipment has been used for inspecting live lines. In this application a high-frequency pulse is used which is coupled to the line by means of a high-voltage coupling capacitor. It is intended to use photographic recording gear with this instrument for the continuous inspection of live lines, in order to locate transient faults such as occur with lightning flashover of live-line insulators. COPYRIGHT 1948 BY THE AMERICAN INSTITUTE OF ELECTRICAL ENGINEERS
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