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on amp。 Control Limited, 1987參考文獻[1] 熊信銀,發(fā)電廠電氣部分(第三版),北京:中國電力出版社,[2] 陳躍,電氣工程專業(yè)畢業(yè)設(shè)計指南電力系統(tǒng)分冊,北京:中國水利水電出版社,[3] 丁毓山 雷振山,中小型,變電所實用設(shè)計手冊,北京:中國水利水電出版社,[4] 陳化鋼, 電氣設(shè)備及其運行, 合肥: 合肥工業(yè)大學(xué)出版社, 2004[5] 賀家李等, 電力系統(tǒng)繼電保護原理, 北京:中國電力出版社,2004.[6] 朱獻清, 物業(yè)供用電, 北京:機械工業(yè)出版社,2003[7] 尹克寧, 變壓器設(shè)計原理, 北京:中國電力出版社,2003[8] :中國水利電力出版社,2002[9] :中國水利電力出版社,2002[10] :中國電力出版社,2004[11] :中國電力出版社,2004[12] . :2327[13] :1418[14] 何仰贊等,電力系統(tǒng)分析,武漢:華中理科技學(xué)出版社, [15] Hologamous Integrating Strategies for Incipient Fault Diagnosis of Transformer,1985[16] Workgroup of GEC AL THOM Measurements. Protective RelaysApplication Guide:3rd Edition . Stafford: GEC AL THOM Protection amp。 Control Limited, 1987 附錄Ⅰ英文資料及其翻譯TransformerTypes and Construction of TransformerA transformer is a device that alternating current electric energy at one voltage level into alternating current electric energy at another voltage level through the action of a magnetic consists of two or more coils wire wrapped around a mon ferromagnetic coils are (usually)not directly connected. The only connection between the coils is the mon magnectic flux presen within the core.One of the transformer windings is connected to a source of ac electric power,and the second(and perhaps third) transformer winding supplies electric power to loads. the transformer winding connected to the power souce is called the primary winding or input the winding connected to the loads is called the secondary winding or input there is a third winding on the transformer,it is called the tertiary winding.Power transformer are constructed on one of two types of type of construction consists of a simple rectangular laminated piece of steel with the transformer windings wrapped around two sides of the type of construction is know as coreform .The other type consists of threelegged laminated core with the windings wrapped around the center leg .This type of construction is know as shell either case,the core is constructed of thin laminations electrically isolated form each other in order in order to reduce eddy currents to a minimum.The primary and secondary windings in a physical transformer are wrapped one on top of the other with the lowvoltage winding an arrangement severs two purposes: simplifies the problem of insulating the high voltage winding from the results in much less leakage flux than would be the two windings were separated by a distance on the core.Power transformer are given a variety of different names, depending on their use in power transformer connected to the output of a generator and used to step its voltage up to transformer levels is sometimes called unit transformer. The transformer ai the other end of the transformer line,which steps the voltage down from transmission levels to distribution levels,is called a substation ,the transformer that takes the distribution voltage and steps is down to the final voltage ai which the power is actually used is called a distribution these devices are essentially the samethe only difference among them is their intended use.In addition to the various power transformer, two specialpurpose transformers are used with electric machinery and power first of these special transformers is a device specially designed to sample a high voltage and produce a low secondary voltage directly proportional to a transformer is called a potential power transformer also produces a secondary voltage directly proportional to its primary voltage。the difference between a potential transformer and a power transformer is that the potential transformer is designed to handle only a very small second type of special transformer is a device designed to provide a secondary smaller than but directly proportional to its primary device is called a current transformer.Cirtcuit BreakersA circuit breaker is mechanical switching device capable of making,and breaking currents under normal circuit conditions and also for a specified time ,and mediujm in which circuit interruption is performed may be designated by a suitable prefix, for example,airblastcircuit breaker,oil circuit circuit breakers currently in use can be dlassified into the following categories according to the arcquenching principles:air swetches oel ciryit breakers,minmumoil circuit breakers,airblast circuit breakers,the magenetic air circuit breakers,minimumoilcircuit breakers,aerblast circuit breakers,the by voltage,insulation levelcurrent,interrupting capabilities,transient recovery coltage,interrupting tiome,and trip nameplate on a circuit breaker usually indicates: maximum steadystate current it can carry, 2. The maximum interrupting current,3. The maximum line voltage, interrupting time in cycles, The interrupting time in may last form 3 to 8 cycles on a 60 Hz system. To interrubt large currents quickly, we have to ensure rapid cooling. Highspeed interruption lunits the damage transmission lines and equipment and, equally important,it helps to mainmain the stability of the system whenever a contingency occurs. The main parts of a circuit breaker are usually:arcquenching chamber (or interrupter with moving and fixed contacts) operating mechanism and supporting structures. Air SwitchesWith increasing currents and voltages, springaction driving mechanisms were developed to reduce contact buring by fasteropening ,main contacts were fitted with arcing contacts of special material and shape,which opend after and closed before the main improvements of the air switch were the burshtype contact with a wiping and cleaning function,the insulating barrier leading to arc chutes,and blowout coils with excellent arcextinguishing features,as well as the horn gap contact,are still in use in low voltage as and de breakers. Oil Circuit Breaker Around 1900, in order to cope with the new requirement for “interrupting capacity”,AC switches were immersed in a tank of oil. Is very effective in quen