{"title":"Novel soft-switching full-bridge converter with magnetic amplifiers","authors":"M. Brkovic, A. Pietkiewicz, Slobodan Cuk","doi":"10.1109/INTLEC.1994.396661","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396661","url":null,"abstract":"A novel full-bridge DC-to-DC converter combines the functions of the lossless soft-switching and secondary side PWM output voltage regulation at constant-switching frequency. The primary side switches of the bridge are driven at constant frequency and near 50% duty ratios with small dead-times, while the output voltage is regulated by PWM control of the magnetic amplifiers on the secondary side. The proposed converter exhibits soft-switching for no-load to full load conditions and maintains high overall efficiency. Experimental results obtained on 300 W, 48 V prototype operated from 300 VDC confirm those features.<<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":"130693732","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":"Analysis and interpretation of conductance measurements used to assess the state-of-health of valve regulated lead acid batteries","authors":"D. Feder, M. Hlavac","doi":"10.1109/INTLEC.1994.396621","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396621","url":null,"abstract":"This paper presents data showing conductance aging of new valve-regulated Pb-acid (VRLA) secondary cells and capacity/conductance aging of older cells. It presents data showing the comparative accuracy of several techniques for selection of a cell conductance value suitable for use in field determination of cell pass/fail conditions based on either capacity failures below 80% or below 50% of rated value. The accuracy of the various selected conductance values are determined by actual comparison to cell by cell capacity/conductance data. This data represents 192 cells of 1000 Ah (ampere hour) size in 48 volt telecom use and 96 cells of 600 Ah size in 24 volt strings in another type of telecom usage. The data presented should allow the user to select a technique which appears most suitable to his needs and capabilities.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"2013 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":"128823336","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}
C. Bose, J.B. Baldasty, M. Weeks, K. Bullock, A. Cannone
{"title":"Design concepts for lead-acid batteries in distributed and bulk power applications","authors":"C. Bose, J.B. Baldasty, M. Weeks, K. Bullock, A. Cannone","doi":"10.1109/INTLEC.1994.396673","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396673","url":null,"abstract":"Valve-regulated Pb-acid batteries in distributed and bulk power applications such as cabinets are often subjected to higher temperature environments. Unless the float voltage is compensated for temperature or the trickle charge current is limited, the battery internal temperature may increase due to heat generated by oxygen recombination. In designing batteries for these extreme environments, case and cover materials must be chosen to minimize water loss, promote heat dissipation and withstand high temperatures. Post and case-to-cover seals must be robust enough to cycle between high and low temperatures under pressurized conditions in which hot acid vapors inside the battery can chemically attack the materials. Standard valve designs are not always reliable at temperatures where frequent pressure release and closure are required. If the valve does not close after the pressure is released, atmospheric oxygen can rapidly discharge the negative plate. Leading to permanent loss of cell voltage and capacity. Other design factors such as the grid material and configuration and plate processing methods reduce internal heating by improving heat transfer and minimizing cell imbalances. In this paper, the authors discuss some of the key design and manufacturing approaches used in secondary batteries to improve their performance in high temperature environments.<<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":"128915025","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 systems for coaxial cable","authors":"D. Weiner","doi":"10.1109/INTLEC.1994.396605","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396605","url":null,"abstract":"This paper is presented to serve as a guide to evaluate or compare different methods of powering a coaxial cable network and addresses both AC and DC options. The criteria used for the evaluations assumed a hybrid network consisting of fiber optic cables routed to a fiber node and then transitioning to coaxial cable. The simulated network handles both video and telephony over coaxial cable. Each fiber node and associated coaxial cable feed up to 480 homes. A maximum of one express amplifier and four line extenders are utilized in any one coaxial feeder. The home or residence is served by a NIU (network interface unit) which separates the video, telephone and any other information or services that may be carried over this network. This document evaluates the different types of powering solutions and should only be used as a reference to the size of the coaxial cable, the current consumption or the amplifiers and the many other factors which affect an actual operating system. All of the power systems discussed provide 8 hours of battery reserve (typical) and do not include redundancy. -130 VDC is not considered as a viable option as it appears that it would have to be limited to 100 VA whether it is contained within the right of way or not in order to comply with NEC and NESC codes.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"32 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":"115026414","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":"Electrical protection for multimedia workstations","authors":"W. Bush","doi":"10.1109/INTLEC.1994.396649","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396649","url":null,"abstract":"Electrical protection for multimedia workstations is essentially dependent upon the product safety listing process. In other words, workstation assemblies and peripherals utilize power, grounding and protection schema that are necessary to obtain the listing mark (such as UL or CSA) for certified product safety. At the time of writing, there is no standard that specifically addresses workstations. This paper explores the acceptability of depending upon just the product safety listing for suitability of electrical protection. A straightforward methodology is applied to determine to what level additional site conditioning may be necessary. The author deliberately utilizes existing codes, standards, draft standards and leading industry articles to illustrate that a straightforward resolution is feasible.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"183 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120863775","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":"High power factor operation of discontinuous current mode series-parallel resonant converter","authors":"V. Belaguli, A. Bhat","doi":"10.1109/INTLEC.1994.396643","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396643","url":null,"abstract":"This paper presents the operating principle, analysis, design, simulation and experimental results for a high frequency (HF) transformer isolated AC-to-DC series-parallel resonant converter (SPRC) operating on the utility line, in discontinuous current mode (DCM). The equivalent models, the state space analysis of the SPRC in DCM are presented. PROMATLAB software is used to solve the equations and to obtain important design parameters. SPICE simulation and experimental results obtained from a 150 W prototype are presented to verify the analysis. High power factor operation (>0.99) with low harmonic distortion (<15%) have been achieved for the entire load range even without active control, in addition to eliminating switching losses.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"33 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":"128588102","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":"Input current controlled DC interconnection converter for fuel cell systems","authors":"Y. Kuwata, T. Babasaki, M. Iwasawa, T. Koyashiki","doi":"10.1109/INTLEC.1994.396641","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396641","url":null,"abstract":"Fuel cells are a remarkably efficient energy generator that also protect the global environment. NTT is developing a fuel cell energy system that supplies generated electrical energy to telecommunications equipment. It is a cogeneration system; the heat energy recovered is used to cool the telecommunications equipment. In a DC interconnection system, along with the commercial AC power, the fuel cell output is fed to the telecommunications equipment through a converter. This paper describes a control method for a new DC interconnection converter and DC interconnection characteristics. The new converter controls its input current to the fuel cell rated current at maximum and can operate stably even when the fuel cell output decreases. Good DC interconnection characteristics can be obtained in the steady state and the transient state.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"71 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":"130849575","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":"Operation of from power soft-switched phase-shifted full-bridge dc-dc converter under extreme conditions","authors":"A. Pietkiewicz, D. Tollik","doi":"10.1109/INTLEC.1994.396663","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396663","url":null,"abstract":"No-load and short-circuit conditions are analyzed for the soft-switched phase-shifted full-bridge DC-DC power convertor topology. Some potential problems are identified and possible solutions are discussed.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"18 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":"122265961","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":"DC-DC converter plants and their ability to clear distribution fuses","authors":"J. Giancaterino","doi":"10.1109/INTLEC.1994.396616","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396616","url":null,"abstract":"Accidental faults in the distribution circuits of DC-DC power converter plants can cause voltage dips below the acceptable operating range of the converter loads. Unlike battery plants, converter plants rely solely upon the power supplies to clear fault protection devices. Since the DC-DC power converters are current limited, their ability to clear faults will be based upon the short burst of current from their output capacitors and the excess current available from the plant. As the technologies have taken the DC-DC power converters to higher and higher operating frequencies, their output capacitance has decreased substantially. In the past, the larger capacitors would provide a higher momentary current when a fault was introduced. In many cases, this is not enough. This paper looks at some of the considerations of converter plants with respect to fault clearing, as well as some practical approaches to resolving this problem. A Lorain 6241 converter plant was tested for its fuse clearing capabilities with and without the additional capacitor bank. The results of this testing are presented.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"35 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":"116725082","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}
F. Vaccaro, J. Rhoades, K. Marion, R. Malley, M. Sirard
{"title":"Valves for immobilized electrolyte lead-acid batteries requirements, design, and performance","authors":"F. Vaccaro, J. Rhoades, K. Marion, R. Malley, M. Sirard","doi":"10.1109/INTLEC.1994.396670","DOIUrl":"https://doi.org/10.1109/INTLEC.1994.396670","url":null,"abstract":"A valve is a device that regulates gas or liquid flow by opening and closing to maintain a predefined condition, whether on the input or exit side of the valve. When employed in the immobilized electrolyte lead-acid battery (IE) the valve's primary functions are to prevent air (oxygen) from entering the cell and to vent excess gasses from the cell. This paper reports on a chronological trace of those inputs necessary to arrive at a bunsen valve for a relatively thin walled plastic battery container. The study begins with design concepts and concludes with the basis for a nonempirical approach to valve design. It is anticipated that this work will aid design engineers in their efforts to provide a satisfactory venting system. Also, the battery user should gain a better understanding of valve performance and characteristics. This knowledge will help in the selection of battery product. Although this paper deals with a specific valve design, i.e. a bunsen cup valve, it can be employed in the conception of most valve configurations.<<ETX>>","PeriodicalId":123164,"journal":{"name":"Proceedings of Intelec 94","volume":"3 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":"131415302","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}