Carrier Communication over Power Lines

Transcription

1 Heinrich-Karl Podszeck Carrier Communication over Power Lines Fourth Revised Edition Springer-Verlag Berlin Heidelberg New York 1972

2 HEINRICH-KARL PODSZECK Chief Engineer of the Power Line Carrier Section Siemens.Aktiengesellschaft, Munich, Germany With 88 Figures ISBN-13: DOl: / e-isbn-13: This work Is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically those of translation, reprinting, re-use of illustrations, broadcasting, reproduction by photocopying machine or similar means, and storage in data banks. Under 54 of the German Copyright Law where copies are made for other than private use, a fee is payable to the publisher, the amount of the fee to be determined by agreement with the publisher. by Sprlnger-Verlag, Berlin-Heidelberg 1963 and Softcover reprint of the hardcover 2nd edition 1972 Library of Congress Catalog Card Number The use of general descriptive names, trade names, trade marks, etc. in this publication even if the former are not especially identified, is not to be taken as a sign that such names, as understood by the Trade Marks, and Merchandise Marks Act, may accordingly be used freely by anyone.

3 Preface to the Fourth Edition Carrier communication over power lines, like carrier traffic over postal lines, has a tradition of about 50 years. It has become a vital element in electric system operation. Being restricted to power networks, it has a comparatively limited scope. Nevertheless, great efforts are being expended on technical advancement to keep pace with the demands made of both power and communication engineering. As in previous editions of this book, it is endeavored in the fourth edition to familiarize the man in the field with the fundamental concepts on which this technique and its practical application are based. The physical and electrical characteristics of the equipment involved are described in a general way. For the sake of clarity, the author has refrained from giving a detailed account or illustrations of special versions, especially as the differences between the equipment supplied by the various manufacturers are so small. This is due to the use of transistors instead of tubes and to the universally adopted plug-in module construction technique. In the load dispatching plants of power supply networks, telemetering systems are turning more and more to data engineering methods and equipment to lighten the task of network management. Consequently, at certain points in the text, topics concerning remote data processing are treated, emphasis being placed on transmission channels operating at a considerably higher speed than was usual 10 years ago. In preparing this new edition, the author was able to draw on the wealth of experience gained in his dealings with ClGRE experts from many countries over the past 20 years. The author endeavored to present the data in a form easily understood both by the power engineer and the communication engineer. A definition of pure communication engineering terms was not felt to be necessary. An index has been provided to assist the reader. Wherever discussion of details would involve undue departure from the main subject, the reader is referred to pertinent publications or to explanations in the appendix. Figures in brackets refer to relevant publications. The text is illustrated by photographs supplied by the manufacturers of the equipment, and certain passages are reproduced from original works with the permission of the publishers. The author extends his thanks to Dr.-lng. E. ALSLEBEN and lng. G. BERGMANN, both of Munich, who assisted him in preparing the fourth edition with contributions and valuable advice. Also, he is obliged to H.HEROLD, Munich, for doing the translation. Munich, in January 1972 H.-K. Podszeck

4 Contents List of Abbreviations... VII 1. Private Communication Networks for Electric System Operation... '" Communication Problems in Electric System Operation Communication Circuits in the Power Network Coupling Circuits Wave Traps By-Pass-Circuits Line Coupling in the Light of New Developments Properties of Power Lines in the Carrier Frequency Range Characteristic Impedance of Overhead Power Lines Attenuation of Overhead Power Lines Coupling Loss Impedance Presented by a Power Network Station Shunting Loss of a Power Network Station Transit Loss of a Power Network Station Characteristic Impedance and Attenuation of Power Cables Attenuation of a Complete Transmission Section Noise Level Characteristics of Power Line Carrier Channels Transmission Systems Bandwidth and Frequency Assignment Transmitter Power and Range Radiation Carrier Communication Networks Frequency Allocation Scheme Telephone Networks Telemetering and Remote Control Networks Transition to Communication Feeder Lines Carrier Current Relaying for Network Protection Portable Carrier Telephone Terminals for Line Crews Carrier Communication Terminals Single-Purpose Equipment a) Telephone Terminals b) Carrier Terminals for Telemetering and Remote ControL..., c) Carrier Terminals for Network Protection and Direct Breaker Tripping

5 VI Contents 7.2 Multi-Purpose Carrier Terminals for Simultaneous Transmission Multi-Purpose Carrier Terminals for Alternate Transmission Multi-Channel Carrier Terminals Survey of Equipment Models Power Supply Measuring Methods and Measuring Equipment Measuring Methods a) Magnitude ofimpedance b) Real and Imaginary Components Measurements on a De-Energized Power Line without Line Equipment 143 a) Characteristic Impedance b) Attenuation Measurements on an Energized Line a) Impedance and Attenuation b) Noise Level Appendix Effect of Spur Lines on Carrier Communication Circuits Effect of Wave Traps Iron-Coated Power Conductors for Network Decoupling Network Decoupling by Four-Pole Circuits Attenuation and Level Amplitude Modulation in Connection with Double-Sideband and Single- Sideband Transmission, Frequency Modulation Send Power and Transmission Range of Carrier Terminals with the Different Transmission Methods a) Transmitter Power b) Noise Level and Signal-to-Noise Ratio c) Gain Factor of Transmission Method d) Practical Application Table of the 4-Digit Mantissae of Briggs' Logarithms Bilbliography Subject Index

6 List of Abbreviations UCPTE Union pour la Coordination de la Production et du Transport de l'electricite AlEE CCITT CEI CIGRE IEC American Institute of Electrical Engineers Comire Consultatif International Telegraphique et TeIephonique Comission Electrotechnique Internationale Conference Internationale des Grands Reseaux Electriques a Haute Tension International Electrotechnical Commission