презентация к уроку Transformers


Чтобы посмотреть презентацию с оформлением и слайдами, скачайте ее файл и откройте в PowerPoint на своем компьютере.
Текстовое содержимое слайдов:

The Topic:Electrical Machines The most prime governing thing that holds for the existence of mankind and the universe and beyond is Energy. From the dark ages, Humans have been trying to develop means and methods to produce energy and then to transform it into another usable form. Even today, our lives are based on Energy. Energy today is now available in many forms for different uses. The most significant type of Energy that has affected our lives in a huge way is the electrical energy. Just turn around your face and you will see electrical devices everywhere around you. Electricity or the popular name for electrical energy as we call it has transformed our lives in a significant way; it has made our lives quite easy and comfortable. HOW IS ELECTRICITY PRODUCED? Electricity (the inevitable thing) is produced by different types of Electric Machines and that too in different forms. The electricity that reaches our home is not a novice task; many genius minds and lots of complex and bulky electric machines are involved behind it. Then an electric machine is not only used for generation purpose it can also be used as a source of mechanical energy that is motor may it be a juicer mixer in your kitchen or the conveyer belt system in large manufacturing plants. So in the next section we will try to explain briefly about basic principle of electric machines and their types. The Topic:Electrical MachinesWhat is an electrical machine?What are their principles of operation, construction?What are they used for?What are their types? What is an electrical machine?An electrical machine converts energy from one category into another. Thereby at least one energy categoryfeatures as electric power.An electrical machine is an energy converter in which two electric circuits have been coupled by means of a magnetic circuit. They all comprise two electric circuits which have been coupled through a magnetic circuit. Going through the basic fundamentals about principle, construction and operation of electric machinesFigure: Tasks of electrical machines in power flow What are the principals of operation of electrical machines?Magnetic fields are the fundamental mechanism by which energy is converted from one form to another in motors, generators and transformers. Two related physical principles underline the operation of generators and motors. The electromagnetic induction The electromagnetic reactiondiscovered by Michael Faraday in 1831If a conductor is moved through a magnetic field, or if the strength of a stationary conducting loop is made to vary, a current is set up or induced in the conductor. If a current is passed through a conductor located in a magnetic field, the field exerts a mechanical force on it. discovered by André’ Ampere in 1820 Functional block diagram of electromechanical energy conversion devices as (A) motor, and (B) generator Vocabulary:feature – особенность, характерная чертаconverter – преобразователь, конвертерcommutator – коллекторarmature – якорьto suggest – предлагать, предложитьring – кольцо, фланец, хомутbar – полоса (металла)to pull – тянуть, притягиватьto switch – включать, выключать, переключатьdrive – передача, приводdesign – конструкция, чертёж, план,to power – снабжать энергией, to differ – различаться, отличатьсяto rotate – 1. вращаться; 2. чередоватьсяto create – творить, создавать Motors and generators’ structure A simple electromagnet consisting of a coil of insulated wire wrapped around an iron coreThe Armature  from a small DC fan motor Electrical Machines Bearers of electric circuits to one anotherrigidflexibleStationary electrical machinesRotating electrical machinessynchronousasynchronouscommutatorstransformersDC MachinesSingle-phaseThree-phase What are these? The subject: TransformersLesson Tasks:To check up our homework;To get information about transformers;to find out what is a transformer;to learn about it’s construction;to know about the types of transformers; Warming-up{5C22544A-7EE6-4342-B048-85BDC9FD1C3A}Column AColumn Barmature a device consisting of a core of magnetic material such as ironelectromagneta device that converts mechanical energy into electrical energycommutator the rotating part of a generator or motorrotora laminated soft-iron core conductora device for reversing the direction of a currentmotora device that converts alternating current to direct currentgeneratora device that converts electrical energy into mechanical energyconvertera material allowing the flow of electric currentinduction the movement of an electric charge in a conductorcurrentthe excitation of the electric current in a conductor Checking-up the h/w / Giving marks {5C22544A-7EE6-4342-B048-85BDC9FD1C3A}Number of mistakes Mark0-3Very Good4-7Good8-15Satisfactory16, ˂ 16Bad Checking-up the Home work / Keys {5C22544A-7EE6-4342-B048-85BDC9FD1C3A}Column AColumn B1) electromagnetic2) rotating3) alternating4) electrical5) high 6) magneticbasicenergyinsulatedconducting induction part current machine voltage field principle converter coil wires{5C22544A-7EE6-4342-B048-85BDC9FD1C3A}Column AColumn B1) electromagnetic2) rotating3) alternating4) electrical5) high 6) magneticbasicenergyinsulatedconducting induction part current machine voltage field principle converter coil wires Checking-up the h/w / Giving marks {5C22544A-7EE6-4342-B048-85BDC9FD1C3A}Number of mistakes Mark0-3Very Good4-7Good8-15Satisfactory16, ˂ 16Bad Text working “Transformers”Vocabulary:{5C22544A-7EE6-4342-B048-85BDC9FD1C3A}winding [‘waɪndɪŋ]primary / secondary windingturnfrequency [‘fri:kwənsɪ]opentrouble (common trouble)shortcoreto step up to step downto increaseto decreaseto substitutedue toобмоткапервичная / вторичная обмоткавитокчастотаобрывнеисправность, (возможная неполадка)короткое замыканиесердечникповышатьпонижатьувеличиватьуменьшатьзаменитьблагодаря, из-за Transformers’ TypesWhat types of transformers are described in the text? What is the work principle of a step-up transformer ? What is the work principle of a step-down transformer ? What is the work principle of an air-core transformer ? What is the work principle of an iron-core transformer ? The subject: TransformersLesson Tasks:To check up our homework;To get information about transformers;to find out what is a transformer;to learn about it’s construction;to know about the types of transformers; Transformers’ Application1. Distribution transformers are generally used in power distribution and transmission systems. 2. Power transformers are used in electronic circuits and come in many different types and applications. 3. Control transformers are generally used in circuits that require constant voltage or constant current with a low power or volt-amp rating. 4. Auto transformers are generally used in low power applications where a variable voltage is required. 5. Isolation transformers are normally low power transformers used to isolate noise from or to ground electronic circuits. 6. Instrument potential and instrument current transformers are used for operation of instruments such as ammeters, voltmeters, watt meters, and relays used for various protective purposes. Transformers’ Application Complex ObjectThe SubjectThe PredicateThe Object (a Noun or a Pronoun in an Object case) The Infinitive (with or without to)The Rest Part of the SentenceComplex ObjectWeconsidera transformer to be an electrical machine.Shewantshim to study English . Complex ObjectПосле глаголов: желания (wish, want, like, would like), предположения (expect, seem, consider, appear, suppose, believe), сообщения/информации (know, think, claim, report, declare, show, find) После глаголов  физическое восприятия и ощущения (notice, see, watch, hear, listen to, observe, feel, ), а также make и letThe SubjectThe Object (a Noun or a Pronoun in an Object case) to + The InfinitiveThe Infinitive The Object (a Noun or a Pronoun in an Object case) Complex SubjectThe SubjectThe PredicateThe Infinitive The Rest Part of the SentenceComplex SubjectThe currentIs knownto consist of moving electrons.SheIs supposedto work at this plant. Complex Subject Сказуемое-глагол в пассивном залоге: to say, to report, to announce, to believe, to suppose, to think, to state, to expect, to know, to consider, to see, to hear Сказуемое в активном залоге: to seem, to appear, to prove, to turn out, to happen, to chance. 3) Сказуемое-глагол to be в выражениях:to be likely, to be unlikely, to be certain, to be sureThe Subjectto + The Infinitive Complex Object / Complex SubjectWesupposehim at this plant.Complex SubjectHeIs supposedto work at this plant.to work Complex Object

Приложенные файлы

  • pptx file3.doc
    презентация к уроку Transformers
    Размер файла: 924 kB Загрузок: 3