{"title":"Communication link between power converters and computer systems for system and alarm management","authors":"H. Bekker","doi":"10.1109/INTLEC.1994.396674","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396674","url":null,"abstract":"Communication between computers and power converters has become more and more important. Communication between power converters and central processing equipment totally changes the traditional routine of maintenance and service departments. Introducing a communication link is a very effective way of controlling the performance of a power converter. However, the way of communication must be carefully selected to avoid getting lost in the many possibilities of remote communication. The author describes how the introduction of a microcontroller in the power conversion control circuitry and the use of a well designed power conversion topology, both electronically and mechanically, ensures a good and reliable flow of power to any critical load, which is of major importance of a power converter system. A good selection of communication between the power converter and a computer system will increase the MTBR values of a system and allows the user to select his load profile more efficiently.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126655534","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":"Maintenance and reliability of standby battery systems: flooded vs. valve regulated lead acid battery","authors":"S. Misra, T. Noveske, A. J. Williamson","doi":"10.1109/INTLEC.1994.396647","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396647","url":null,"abstract":"Flooded and VRLA cells should be considered as battery types which complement each other. VRLA cells are here to stay because of their gas-free nature, low maintenance, and high energy density. They should not be considered indiscriminately as substitutes for flooded cells. The special sensitivities of VRLA should be taken care of in a system approach. In particular the system float voltage should be reviewed, and adjusted for significant temperature excursions. A system reliability should include continuous monitoring of module voltage, current and temperature, and action steps and safeguards built-in to avoid thermal problems.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132345336","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 new generation of board mounted modules for telecom","authors":"B. Brakus","doi":"10.1109/INTLEC.1994.396593","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396593","url":null,"abstract":"The rapidly increased processing density within switches has caused decisive changes in power supply architecture and design. As a result, two main effects can be observed: board-mounted power supplies have gained more ground, since the single system board becomes a closed functional unit; and the increased power density requires highly efficient low profile power modules, optimized for forced cooling. Following comprehensive studies of a suitable power converter topology, the power supply department of Siemens' Public Switch Division designed a new family of board-mounted DC/DC modules. Employing the advanced thick-film hybrid technology based on ceramic substrates, four basic modules for 5 W, 15 W, 30 W and 60 W have been created. This paper presents this circuit topology based on an f-modulated forward-type power converter with a frequency maximum of 700 kHz. For this purpose, a special control IC has been designed. The main goals of high frequency conversion (such as low profile magnetics, ceramic capacitors, light weight, low profile design) have been fully realised. The technological highlights, such as the dice in globe-top-technique, multilayer hybrid design, active and passive laser trimming, are discussed. The practical results of the present module family are commented upon.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117322683","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":"Tests on valve regulated lead acid batteries at different environmental temperatures and float voltages","authors":"R. Elgh","doi":"10.1109/INTLEC.1994.396658","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396658","url":null,"abstract":"This paper describes the behaviour of two different types of valve regulated lead acid batteries which have been exposed to environmental temperatures between 22 and 37/spl deg/C and at different float voltages. Temperatures inside the batteries and float currents are monitored. Significant difference in performance have been observed between the two battery types.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130661085","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":"Environmental issues in remote telecommunications sites: hydrogen evolution of VRLA batteries in cellular installations","authors":"P. Casson, D.C. Dunsworth, J. Robbins","doi":"10.1109/INTLEC.1994.396660","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396660","url":null,"abstract":"Modern telecommunications deployment increasingly involves the use of remote sites. Equipment is housed in enclosures that range in size and scope from large concrete buildings containing entire switches to small cabinets containing a few lines of transmission equipment. In most cases, reserve energy during AC power failures is supplied from lead acid batteries collocated with the electronics within the enclosure. The fact that all lead acid batteries generate hydrogen continuously during their operation is an important design parameter for both the enclosure, and the equipment which the batteries are designed to support. While much published material has dealt with VRLA battery operational issues such as hydrogen evolution and thermal runaway from a design and engineering viewpoint, this investigation has attempted to represent a users perspective. In determining the capabilities and limitations of both the batteries and their end users the paper attempts to present some real world principles to aid successful applications. While predominantly focussing on wireless, such principles could also apply to other outside plant type applications.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124891613","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 novel ring network for telephone exchange's rectifier system","authors":"C. Vun, B.S. Lee, C.T. Lau","doi":"10.1109/INTLEC.1994.396598","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396598","url":null,"abstract":"This paper describes a novel ring network based on the SDLC data link transmission protocol that is specifically designed to be used for the new generation of microprocessor-based rectifiers. The network protocols proposed allow a central computer to supervise and maintain the rectifiers that are used in a telephone exchange station more efficiently as compared to the other commonly used methods for such a system.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122597412","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":"Imperfectness as a useful approach in battery monitoring","authors":"T. Suntio","doi":"10.1109/INTLEC.1994.396625","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396625","url":null,"abstract":"Ability to monitor secondary battery state of health and state of charge has become increasingly important. Earlier methods were entirely based on cell or block voltages. In the case of valve-regulated batteries, information of plain cell or block voltage can no longer be used as a sign of failure due to high normal deviation. Discharging a battery is still the only reliable method by which battery state-of-health and state-of-charge can be verified. This paper describes a practical and simple method, as well as the circuitry used, for a battery monitor. The method is based on measurement and comparison of the voltage differences of series connected battery blocks in a way which reduces the number of measurement channels as well as comparisons. For a typical 24-cell battery string containing four 12 V monoblocks, the measuring channels and comparison needed are three. The monitoring process also contains periodical battery discharges. The discharge interval and time can be chosen to ensure sufficient reliability and availability performance of the battery system.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"39 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128985083","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":"Computer simulation and verification of DC power plants for seismic qualification","authors":"G. K. Crowe","doi":"10.1109/INTLEC.1994.396650","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396650","url":null,"abstract":"Power plant integrity and resistance to earthquakes are of special interest to those living in areas of high seismic risk. Power products must be designed and tested to ensure survivability. A cost effective analytical approach using PC based software is described and verified. Medium sized power plants are selected for structural examination. They are -48 VDC plants with maximum current capacity of 600 A. The plants are modular, mounted on a seismic, free standing equipment rack. The modularity is provided by interchangeable functional blocks or panels. Being modular, the plants provide for a variety of configurations. The total weight, center of gravity and eccentricity will change or shift as modules are added, subtracted or interchanged. Finite element analysis (FEA) is a cost effective way to determine the structural impact. FEA may be applied to all configurations with confidence once one set of analysis results has been confirmed by testing.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"2016 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127457989","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 new current programming technique using predictive control","authors":"P. Shanker, J.M.S. Kim","doi":"10.1109/INTLEC.1994.396633","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396633","url":null,"abstract":"This paper investigates a new current programming technique for constant frequency switch-mode power converters. In the proposed technique, the duty cycle of the power converter switch is controlled by the input and output voltage as well as inductor current information. The basic idea in predictive control is to force the inductor current to follow the command current within one switch cycle. This new technique removes several drawbacks of conventional current mode control, such as current loop instability and error between inductor peak current and command current. The boost power converter is used as an example of the implementation of this new technique.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127556750","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 single phase quasi-resonant rectifier with unity power factor","authors":"G. Moschopoulos, G. Joós","doi":"10.1109/INTLEC.1994.396611","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396611","url":null,"abstract":"Typical boost power factor correction (PFC) circuits have significant switching losses which reduce their efficiency. Resonant PFC circuits have been proposed to overcome this drawback but these circuits operate with higher RMS currents and thus higher conduction losses. A single phase, quasi-resonant rectifier that operates with unity power factor and with reduced conduction losses is proposed. In the paper, the modes of operation of the converter are explained and analyzed, the method of input current control is discussed, and a design procedure is derived. The feasibility of the converter is shown with results obtained from computer simulation.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121131799","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}