Application of Broadcast FM for Utility Energy Management Communications
Technological and economic aspects of various approaches to electric utility Energy Management communications for remote control are discussed. Communication systems employing radio frequency (RF) transmission techniques are treated in some detail with comparisons being made between narrow- band VHF transmitter systems, those systems utilizing a portion of AM broadcast radio channels and systems using a portion of FM broadcast radio channels. Finally, typical utility energy management applications of these-systems are discussed.
Electric power load management: Some technical, economic, regulatory and social issues
This paper provides a review of the subject of electric power load management. In Section I, we briefly introduce the topic and then provide a summary of the current operating characteristics of electric energy production and delivery (EEPD) systems. Section II places load management in the context of the broader set of energy management strategies available to EEPD systems. The organization and rationale of the paper is then explained. In Section III, we review the set of communication/control technologies available or under development for use in the implementation of load management in EEPD systems. We provide an assessment of the relative attractiveness of alternative technologies, a brief summary description of a major field demonstration being jointly funded by EPRI and DOE, and two examples which illustrate the state of the art in modern two-way systems. In Section IV, we review the conventional approach to U.S. electric rate design, describe the current national Electric Utility Rate Design Study, review some important basic ideas of microeconomics, explore the subject of price elasticity of demand, examine the basic ideas underlying marginal cost pricing, discuss some of the practical difficulties of implementing time dependent rates, briefly examine some foreign rate design experience, and conclude by summarizing a number of U.S. rate design experiments sponsored by NSF and by FEA (now DOE). Section V is devoted to an examination of the problems of finding manageable loads in the residential, commercial, industrial, and transportation sectors. Particular attention is given to the development of thermal storage systems for water heating, space heating, and space cooling. Section VI is devoted to summarizing a number of studies which have attempted to assess the short- and long-term economic impacts of load management. The state of the field is such that few definitive cost/benefit statements can be made at this time. A number of potential social impacts are discussed and some broad regulatory policy guidelines are suggested. Finally, in Section VII, we highlight conclusions reached in the five preceeding sections, and identify a number of research and policy needs.
Prediction of a representative point for rail temperature measurement by considering longitudinal deformation
Monitoring rail temperature is very important for determining the safe running speed of trains and to prevent buckling. In general, the maximum variation of the internal rail temperature can be >7 ℃ depending on the point of measurement. However, there is as yet no sufficient information about how to predict the measurement point to represent the thermal deformation due to temperature distribution. In this study, the authors report a new point, called the representative measurement point, at which the rail temperature can be measured. This point considers the average deformation of the rail through structural analysis by adopting experimental and actual rail temperature data. The authors designed and installed a measurement system similar to an actual rail environment. Using the system, various data were acquired (internal/surface rail temperature and weather data) for 10 months. On the basis of these data, an analysis was done to calculate the average deformation point through thermal analysis. Finally, the representative measurement point was proposed as the position at which the average deformation point converges regardless of weather or seasons. The authors believe that the method described herein is advantageous in that it could be used in a high-accuracy temperature-monitoring system and for predicting thermal deformation and buckling.