{"title":"The State-of-Art Space-Voltage Vector Modulated Sinusoidal Three-Phase Inverter with High-Frequency Transformer-Coupled Resonant DC Link for High-Power Density UPS","authors":"H. Yonemori, M. Michihira, M. Nakaoka","doi":"10.1109/TELESC.1994.4794371","DOIUrl":"https://doi.org/10.1109/TELESC.1994.4794371","url":null,"abstract":"Newly-improved Quasi-Resonant DC Link (QRDCL) three-phase voltage-sourced inverter circuit topology operating under a commutation principle of the high-frequency (HF) transformer-assisted Zero Voltage Switching (ZVS) is proposed. The basic operating principle of this power conversion circuit using Auxiliary Transformer-assisted QRDCL (TQRDCL) more suitable for CVCF/UPS, power active filter, switched-mode PWM converter, and new energy-interfaced power supplies for utility-interactive interconnection is presetted in this paper, Its operating characteristics are discussed and evaluated in terms of using the computer-aided simulating results. The experimental circuit is tested and examined for CVCF/UPS systems. This tested equipment is discussed for linear and non-linear electrical loads under the conditions of large load variations and voltage fluctuations from a practical point of view.","PeriodicalId":178715,"journal":{"name":"TELESCON '94 - The First International Telecommunications Energy Special Conference","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115341353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Principles of Function, Construction and Application of Valve Regulated Lead-Acid Batteries","authors":"D. Kunze","doi":"10.1109/TELESC.1994.4794379","DOIUrl":"https://doi.org/10.1109/TELESC.1994.4794379","url":null,"abstract":"One of these parasitic reactions is the electrolytic decomposition of water (hydrolysis) in the electrolyte, thereby developing the gases oxygen and hydrogen. The decomposition-potential of water (1.23 volts at 25°C) is far below the equilibrium potential of a lead-acid battery (ca. 2.1 volts). The rate of this reaction rises exponentially with the potential (by a factor 10 for every 0.2 volts in conventional batteries). During the charging of a battery, more and more water is decomposed with rising state of charge and potential.","PeriodicalId":178715,"journal":{"name":"TELESCON '94 - The First International Telecommunications Energy Special Conference","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122543288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Load Sharing in High-Reliability AC-DC and DC-DC Converter Power Systems","authors":"A. Kislovski","doi":"10.1109/TELESC.1994.4794370","DOIUrl":"https://doi.org/10.1109/TELESC.1994.4794370","url":null,"abstract":"The high reliability of power systems utilizing paralleled rectifiers or converters is based on redundancy of individual modules. This paper traces the origines of the load-sharing approach to airborne electromechanical power systems and highlights the fundamental features of today's state-of-the-art approaches. The emphasis is on the over-all performance, reliability and user-friendliness.","PeriodicalId":178715,"journal":{"name":"TELESCON '94 - The First International Telecommunications Energy Special Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129462160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Evolution of Telecommunications and the Impact on CO Power Architectures","authors":"N. Osifchin, J. Horzepa","doi":"10.1109/TELESC.1994.4794308","DOIUrl":"https://doi.org/10.1109/TELESC.1994.4794308","url":null,"abstract":"The evolution of telecommunications in the USA and its impact on CO Powering architectures is reviewed in two time eras: prior to divestiture of AT&T in 1984 and ten years after divestiture. A possible scenario for the next ten years is also presented. Advances in technology together with competition has spurred the introduction of digital electronics, fiber and wireless to create telecommunications networks with broad bandwidths and capable of providing an array of voice, data and image services to any place and any time. To support these networks, power technology has responded with distributed architectures and smaller, lighter, more flexible, more efficient and lower cost rectifiers, dc/dc converters, dc/ac inverters, and batteries more compatible with the new environment Power processing has steadily moved closer to the electronics; into system frames in COs and closer to the customer in the field. This distributed architecture together with microprocessors has spurred the development of power system controllers that will be integrated into end-to-end network system management.","PeriodicalId":178715,"journal":{"name":"TELESCON '94 - The First International Telecommunications Energy Special Conference","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128141347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Seismic Analysis of Telecom Battery Racks","authors":"B. Regvart, H. Franke","doi":"10.1109/TELESC.1994.4794373","DOIUrl":"https://doi.org/10.1109/TELESC.1994.4794373","url":null,"abstract":"Earthquakes have a potential to cause serious damages to telecom system and jeopardise its continuos communication service availability. The battery is a vital part of uninterruptible power supply system for telecom equipment. Its function is to provide dc. energy without interruption at mains failure or until a standby diesel generator is started up. The learning and challenges of earthquakes have been presented in many papers. According to the study of the earthquake made by author in paper [1] during the commercial outage after the earthquakes some standby diesel generators failed to start. If this occurs the battery as a standby unit for mains or diesel generator failures takes over the feeding of telecom equipment. The traditional power system for telecom plant, composed of thyristor controlled rectifiers and conventional battery has been installed separately from telecom equipment. Generally, large conventional batteries are located on basement or the first floor in the telecom building. In many countries the conventional vented lead acid battery is replaced by valve regulated lead acid (VRLA) battery that can be put in the room of telecom equipment. Telecom system with incorporated VRLA cells of battery can be found on different floors of a telecom building. Depending on location of VRLA batteries in telecom building and seismic zones some telecom organizations require analysis of battery racks resistant to earthquakes. This paper deals with two different techniques in analysis of telecom battery racks resistant to earthquakes. classified with the aid of various scales. Since 1964. empirical MMS scales have been used in civil engineering in Europe. Earthquakes in MMS scales are classified in degrees of intensity according to their effects at human senses and building damages. In most countries magnitude scales are used (i.e. Richter). Magnitude scales are based on the recorded values of seismic energy released at an earthquake. Table 1. show the relationship between MMS and Richter scales and ground acceleration levels during earthquakes in various seismic zones.","PeriodicalId":178715,"journal":{"name":"TELESCON '94 - The First International Telecommunications Energy Special Conference","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125613086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Power supplies for customer premises telecommunications equipment","authors":"N. Asano, K. Tsutsui, T. Yamashita, S. Furubo","doi":"10.1109/TELESC.1994.4794313","DOIUrl":"https://doi.org/10.1109/TELESC.1994.4794313","url":null,"abstract":"High performance and visual telecommunications equipment based on network digitization have been introduced. Portable equipment such as portable telephones is also coming into wide use. This has resulted in many new requirements for power supplies for this equipment. This paper examines power supplies for these customer premises telecommunications equipment in Japan. The requirements, design concept, features and future work are described.","PeriodicalId":178715,"journal":{"name":"TELESCON '94 - The First International Telecommunications Energy Special Conference","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115525930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Installation of Energy Saving A/C-Systems for Telecom Centres in the Czech Republic and the Slovak Republic","authors":"Peter Wulff, Zdenek Kvarda","doi":"10.1109/TELESC.1994.4794358","DOIUrl":"https://doi.org/10.1109/TELESC.1994.4794358","url":null,"abstract":"As the result of world war I1 and the division of Europe into a western democratic part and a totalitarian eastern block, the subsequent creation of the \"Iron Curtain\" involved the obstruction of communication between East and West. Since telecommunication in the eastern block countries was not considered desirable, the modern electronic digital technique in use in the West was not introduced in the East. With the Berlin Wall coming down in 1989 and the abolition of the regime in power at that time, the Czech Republic and the Slovak Republic decided for a gradual but extensive reconstruction of their inadequate and antiquated telecommunication network including the equipment for digital exchange stations.","PeriodicalId":178715,"journal":{"name":"TELESCON '94 - The First International Telecommunications Energy Special Conference","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117319407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Single Switch Wide-Input-Range AC-DC-Converter with Power-Factor-Correction for Isolated Output","authors":"M. Emsermann","doi":"10.1109/TELESC.1994.4794328","DOIUrl":"https://doi.org/10.1109/TELESC.1994.4794328","url":null,"abstract":"The demands of the IEC 555 standards call for high power factor AC/DC converters to fulfill the harmonic components requirements. A conventional designed converter would include two power stages: one AC/DC converter for the power factor correction and one DC/DC converter including the main to output safety isolation. In this paper a single stage power converter including power factor correction and primary secondary isolation is presented. The converter was designed to fullfil the requirements of EN 60950 and the IEC 555-2.","PeriodicalId":178715,"journal":{"name":"TELESCON '94 - The First International Telecommunications Energy Special Conference","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123463676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A History of the Development of Power and Building Engineering Services in Telecommunications, Telecommunications Energy Special Conference a Satellite Conference to INTELEC","authors":"J. Parsons","doi":"10.1109/TELESC.1994.4794309","DOIUrl":"https://doi.org/10.1109/TELESC.1994.4794309","url":null,"abstract":"Telecomms Power and Building Engineering Services (BES) plant has come a long way since the 1930's. On the DC side, equipment has developed from on site generation of DC power, to distributed switch mode power supplies. AC standby plant has progressed from zero provision to fully automated packaged engine sets, and ventilation requirements have advanced from openable windows, to temperature controlled sites with microprocessor controlled Air Handling Units (AHU's). Advancements in technology, energy considerations and careful design, have all played a part in producing AC, DC and BES plant that is purpose built to reliably support modern switches. In recent years there has been continual reduction in available resource and this, coupled with the privatisation of PTT's and regulated competition, has increasingly played a role in developing remote surveillance and alarm collection systems. As competition increases, and in-house resource decreases, the need to cut costs will be accelerated. More use will be made of external contractors for maintenance and installation work, and more commercially available equipment will be purchased. Energy constraints will require more efficient plant and more developments will be targeted at reducing the standing loads on power plant. This will be particularly applicable in new technology areas, such as telecommunications over passive optical networks (TPON). This paper describes some of the developments that have taken place in the past and suggests factors that will impinge on Power and BES for telecommunications in the future.","PeriodicalId":178715,"journal":{"name":"TELESCON '94 - The First International Telecommunications Energy Special Conference","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128216871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Rectifier Module 48/60V-120/100A with Sinusoidal Input Current","authors":"Wilhelm Sabadi","doi":"10.1109/TELESC.1994.4794329","DOIUrl":"https://doi.org/10.1109/TELESC.1994.4794329","url":null,"abstract":"","PeriodicalId":178715,"journal":{"name":"TELESCON '94 - The First International Telecommunications Energy Special Conference","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121451493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}