变压器铁损和铜损的几种测定方法

用多种方法对变压器的铁损和铜损进行了实验测定，并进一步分析了实验结果，认识了铁损和铜损的实质。     

理想变压器的种种“理想”

理想化是物理学重要的研究方法,理想变压器是忽略了漏磁、铁损、铜损和励磁电流等因素的理想化模型。当变压器在空载时,励磁电流不能忽略;当变压器副线圈短路时,铜损不能忽略,不能认为是理想变压器。     

高损变压器改造计算机软件包

本文提出了一个新观点，认为高损变压器改造适宜以用户年变电成本作为主要判据，改造效益与当地电价、材料价、劳务价以及原变压器参数有关，所编制的计算机包可以进行多种方案比较，从而使用户作出最佳方案选择。最后本文以广东珠江三角洲为例指出该地区高损变压器改造可望获得较大收益。     

高考中的变压器问题导析

变压器是电磁感应现象的实际应用．中学物理研究的变压器是不计铁损、铜损、磁损的理想变压器，用于计算的公式有U1/U2=n1/n2、l1/l2=n2/n1和P人=P出，所以，就变压器这节内容本身没有多大的思维难度．但对于那些不拘泥于教学大纲，构思新颖，立意创新的变压器问题，学生分析解答时不能很好看清物理模型、不注意适用条件、不分清特殊情况、不辨析因果关系，往往盲目代公式．因此，学习中既要抓基础知识、     

试析变压器节能增效的措施

单台变压器运行时，为使效率最高，其负荷的大小必须在一定的范围内；多台变压器并联运行时，为使效率最高，要根据负荷的大小及变化情况确定变压器运行的台数，这样才能做到使变压器经济运行。针对变压器的实际使用情况，提出了具体的节能增效的措施，并进行了相应的理论分析。     

变压器运行方式对降低网损的影响

变压器采取何种运行方式．以及运行方式是否经济,对降低系统的网损有重要的影响。本文对变压器的经济运行进行了探讨。     

主变压器油介损超标的分析及处理

本分析220KV漳州总山变电站2号主变绝缘油介质损耗超标的原因。通过现场取证和试验数据，阐明降低绝缘油介质损耗的处理措施和处理流程。为今后变压器油介质损超标诊断及处理提供借鉴。     

电力变压器低压引线新型接法的探讨与应用

电力变压器传统的低压引线四螺旋结构由于直流电阻不平衡的原因，导致变压器内部产生环流从而增加了变压器损耗，降低了效率。引入新型的接法，可以使直流电阻不平衡率降低一倍。     

变压器原副线圈电流关系实验的商榷

变压器原副线圈电流关系实验的商榷黄柱南（广西容县高中，５３７５００）关于变压器原、副线圈的电流Ｉ１、Ｉ２之间的关系，高中物理第二册（必修）课本是根据变压器消耗的功率很小、效率很高，然后直接用直流电功率公式写出Ｉ１Ｕ１＝Ｉ２Ｕ２．由于这种方法不严密，高...     

地区电网经济调度的主要手段分析

结合电网的实际运行情况,对地区电网经济调度进行了研究,提出了精心编制运行方式、实现无功就地平衡、合理调节运行电压、科学调整负荷曲线、组织变压器经济运行、合理安排检修计划等手段,从而达到降低电能损耗,实现电网经济运行的目的。     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.     

Improvement of one-cycle controller by use of proportional integral differential controller

1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…     

库克斯顿城堡

城堡, 是欧洲典型的建筑之一, 每个城堡都有一个美丽的传说或是一段历史。从本期开始, 我们将推出“城堡之旅”, 带各位读者去浏览、观赏欧洲各地的城堡, 开始一段文化与历史的旅途!     

The Reader Response Approach to Teaching of English Literature

During interview with English majors, it was found that a majority of students expressed disappointment with their experience of English literature classes. Students' dislike of learning English literature appears to be the major problem of teaching English literature in China. Reader response approach is a good way to solve this problem. In this paper, I explain the rationale behind the reader response approach, such as its origin, definition, features, assumptions, and strategies. Then I illustrate how reader response approach works as a teaching strategy by presenting several teaching models. At last I evaluate its usefuiness for teachers and present the advantages of reader response approach in Chinese context.