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Text 1. Fundamentals of electricity




АНГЛИЙСКИЙ ЯЗЫК

 

Министерство образования и науки Российской Федерации

ФГАОУ ВПО «УрФУ имени первого Президента России Б.Н. Ельцина»

 

 

АНГЛИЙСКИЙ ЯЗЫК

Учебно-практическое пособие по обучению чтению

Научно-технической литературы по специальности

Электротехнического факультета

«Электротехника»

(для групп коррективного курса)

 

 

Екатеринбург

УрФУ

УДК 002=111 (076.6)

 

Авторы-составители: Т. Ф. Пименова, Ж. А. Храмушина

Научный редактор: проф., д-р техн. наук А. В. Паздерин

 

 

АНГЛИЙСКИЙ ЯЗЫК: учебно-практическое пособие

по обучению чтению научно-технической литературы / авт. сост.

Т. Ф. Пименова, Ж. А. Храмушина. Екатеринбург: УрФУ, 2010, 74 с.

 

 

Предназначено для студентов Электротехнического факультета групп коррективного курса. Цель пособия – развитие навыков и умений, направленных на практическое владение английским языком, таких как навыки перевода технического текста, умение работать сл словарем, умение извлекать информацию на материале текстов, формирование навыков говорения по тематике специальности. Все тексты взяты из оригинальной литературы по специальностям электротехнического факультета, переработаны и адаптированы. Тексты сопровождаются тренировочными упражнениями по терминологии.

Прил.2.

 

Подготовлено кафедрой иностранных языков

 

 

© УрФУ, 2010

 

 

ОГЛАВЛЕНИЕ

Урок 1. Unit 1. 5

Урок 2. Unit 2. 10

Урок.3. Unit 3. 15

Урок 4. Unit 4. 21

Урок 5. Unit 5. 26

Урок 6. Unit 6. 33

Урок 7. Unit 7. 38

Урок 8. Unit 8. 43

Урок 9. Unit 9. 50

Урок. 10. Unit 10. 53

Приложение 1. Слова и выражения для тренировки навыков

разговорной речи. 67

Приложение 2. Структура простого предложения и

грамматические модели. Структура простого предложения 74

 

УРОК 1. UNIT 1.

1. Прочитайте слова, обращая внимание на чтение подчеркнутых букв и

буквосочетаний в ударных слогах.

 

oper a tion el e ctric s y stem c o mplex

b a sic eff e ctively eff i ciently o perate

altern a ting n e cessary e lectr i city gr o ss

ch a nge personn e l b u siness bec au se

displ ay ed exc e ss i ndustries o pposite

s a me st ea dily del i very acc o mmodate

w ay eff e ct fac i lities v o ltage

m a de m ea surement d i gitally f o llowing

sh a pe r ea dily compos i tion w a tt

 

disp a tch f u ndamental prov i de ret ur ned

m a gnet c u stomer l i ght c ir cuit

underst a nding c u rrent appl i ed p er

m a ximum o ne p i pe t er med

g a llons d oe s t y pe c er tain

b a ttery cond u ctor rise th er mocouple

a tom res u lt t i me ref er

m a nner o ther s i ze transf er

ch a racteristics s u bstance pr i me conv er t

 

compl e ting u sed ent ire s our ce

rep ea ted u nit sc ie nce a lternating

m e ter c u bic w ire c a lled

ea ch f ew h igher f or m

f ee t prod u ce des i rable c au se

m ea ns u tilize env i ronment f or ce

ea sily rev iew requ i red au tomatic

h ea t f u el f i re a ll

imm e diately u sually violent imp or tant

 

air p ower g oa l ap ar tment

comp are d our h o me pl a nt

v a rious hour fl ow ing ch ar ge

th ere t ower l oa d br a nch

th eir fl our l ow f ar

v a ry fl ower c oa l p a ss

c are ful s our bel owar ticle

w here sh ower kn ow n h ar mful

b are p ower ful contr o l adv a ntage

 

2. Прочитайте и запомните следующие слова и словосочетания.

 

to operate – действовать, работать, приводить в действие;

to dispatch – распределять нагрузку;

a business – торговое предприятие, фирма;

to complete – завершать, заканчивать; замыкать;

unidirectional – однонаправленный (ток);

to rise – подниматься, повышаться, нарастать;

to increase – возрастать, увеличиваться;

to decrease – уменьшаться, снижаться;

by means of – посредством, с помощью;

in the same manner – таким же образом;

a junction – соединение;

to turn on / off – включать / отключать, выключать;

a means of – средство.

 

3. Прочитайте текст 1. “Fundamentals of Electricity”, подчеркните во всех предложениях подлежащее (одной чертой), сказуемое (двумя чертами), определение (волнистой линией). Определите грамматическую модель каждого предложения.

 

TEXT 1. FUNDAMENTALS OF ELECTRICITY

The operation of an electric system is not complex. To effectively and efficiently operate and dispatch in an electric system, a fundamental understanding of basic electricity is necessary.

Electricity is used to light homes, businesses and operate industries. When a water delivery system has water flowing, the water flows to the customers by pipes. The excess water is not returned directly to the source. In electrical systems, electricity flows to the customers by wire. In an electrical system, the current is returned to the source, completing the circuit. There are two types of electric current: direct current (DC) and alternating current (AC).

Direct current is so called because it flows directly to the load and returns to the source. It is unidirectional by character.

Alternating current does not immediately change its direction. The change rises to a maximum flow in one direction, and then it decreases to zero. Next it rises to a maximum flow in the opposite direction, and then decreases to zero. This entire sequence is called a “cycle”. In power systems, the frequency of complete cycles is repeated 60 (sixty) times each second.

Current flow is expressed in units termed amperes (amps). This is similar to the measurement of the water flow by units called cubic feet per second or gallons per second. Amperes are read by means of ammeters or displayed digitally.

All substances do not accommodate electrical current flow in the same manner. Materials which readily allow current flow are termed “conductors”. Materials which do not readily allow current flow are termed “insulators”.

There are six main ways to produce electricity. Electricity may be produced by means of friction. Friction is used to produce electricity by rubbing two materials together. Electricity may be produced by pressure. Pressure can be utilized to produce electricity by applying pressure to a crystal of certain materials. The crystal is placed between two metal sheets with pressure being applied. Then voltage can be registered between the two plates. Certain crystals which possess this particular characteristic are quartz and tourmaline. Electricity may be produced by heat. This is exhibited in the form of a thermocouple. A thermocouple uses two dissimilar metals. The two metals are subjected to the direct action of heat and can cause electricity at the junction of these two metals. Electricity may be produced by chemical reaction. The current delivered by batteries is termed DC. Electricity may be produced by light. Light may be used to produce electricity in the action of light striking photosensitive materials. The photovoltaic effect is used in the form of a light meter which utilizes a selenium alloy iron and a transparent material. Photocells used in turning on and off lighting systems also utilize this means of producing electricity. Electricity may also be produced by magnetism. Magnetism may be used to produce electricity by utilizing the relative movement of a magnet and a wire. This will result in the cutting the lines of force. Anytime the lines of force are cut by a conductor, electricity is produced.

 

4. Найдите в каждом ряду слово, перевод которого дан в начале ряда:

 

1) работа, управление – work, operation, job

2) подача питания, доставка – delivery, transfer, flow

3) потребитель – buyer, customer, operator

4) провод, проводник – customer, load, wire

5) электрическая цепь, контур – wire, line, circuit

6) электрический ток – current, customer, conductor

7) нагрузка – line, load, flow

8) частота – frequency, voltage, current

9) напряжение – frequency, voltage, current

10)фотоэлемент – photoactor, photocathode, photocell

 

5. Найдите в тексте английские эквиваленты следующим словосочетаниям и фразам.

 

1) чтобы эффективно и рационально управлять

2) используется для освещения

3) считываются с помощью

4) не проводит поток тока

5) к ним и прилагается давление

6) можно отметить, зарегистрировать

7) это демонстрируется

8) подвергаются непосредственному воздействию

9) может вызвать появление электрического тока

10)это приведет к пересечению

 

6. Ответьте на следующие вопросы.

 

1) Where is electricity used?

2) What types of electric current are there?

3) What is the basic difference between direct current and alternating current?

4) What units are used to measure current?

5) Is there any difference between conductors and insulators?

 

7. Назовите основные способы получения электрического тока.

 

8. Переведите текст на русский язык.

 

 

УРОК 2. UNIT 2.

1. Прочитайте следующие слова, обращая внимание на чтение

подчеркнутых согласных букв и буквосочетаний.

 

c onsidering c ircuit surrounding s flu x

c urrent s in c e flow s ma x imum

cir c uit c ycle si z e e x plain

magneti c s ine increa s ing basi cs

c an c ertain oppo s e s e x cess

cy c le resi s tan c e re si stive mi x ing

c ause s ame z ero e x press

pea k re c eive ri s e e x change

che ck lo ss degree s a x ial

 

effi c iency direc tionwh ich v oltage

accompli sh alterna tionw ill de v ice

sh ape situa tionw ave v alue

ra ti o opera tionwh ere wa v e

poten t ial induc tionw ould v oltmeter

ter t iary connec tionwh en relati v e

establi sh sec tionw ire subdi v ision

pre ss ure transmi ssionw ound v ery

sh ould propor tionw inding di v ide

 

be h ind ch ange e qu ip ma g netic

h inder ac t ually e qui pment ma g nitude

h ave rea ch e qu al la g

h igh ch eck re qu ire de g ree

h andle mu t ual e qu ivalent re g ard

wh o combus tio n qu ick fi g ure

wh ose fea t ure s qu are to g ether

wh ole struc t ure qu ality ne g ative

wh om manufac t ure qu antity lan g uage

 

volta g e bo thth en alternati ng

lar g e some th ing th ere surroundi ng

ener g y th ird th at si ng le

ener g ize th rough th ey ba n k

g enerator no th ing th is windi ng

dama g e me th od th ese meteri ng

in j ury streng th ano th er relayi ng

a dj ustable th ick wi th in readi ng s

chan g e ma th ematics wi th out stre ng th

 

2. Прочитайте и запомните следующие слова и словосочетания:

 

an alternating current circuit – цепь переменного тока;

a magnetic field – магнитное поле;

inductance – индуктивность; самоиндукция, собственная индукция;

both the current and the voltage – и ток, и напряжение;

magnitude – амплитуда;

to lag behind – отставать, запаздывать;

an induction motor – асинхронный двигатель;

a transformer – трансформатор;

a reactor – (электрический) реактор; катушка индуктивности;

to energize – включить(подать) напряжение; возбудить;

to de-energize – отключать, снимать напряжение; обесточивать; снимать

возбуждение;

a collapsing field – (зд.) перенапряжение

to flash over – вспыхивать; искрить;

a circuit breaker – автоматический выключатель;

a field breaker – автомат гашения поля;

a coil – катушка (индуктивности);секция обмотки (катушки); намотка;

обмотка;

a turn – виток; оборот;

spacing – расстояние; интервал; промежуток;

a winding – обмотка;

power operations personnel – оперативный персонал;

to transfer power – переносить; передавать энергию;

a core – сердечник; стержень;

mutual inductance – взаимная индукция;

self-inductance – собственная индуктивность, самоиндукция;

 

3. Прочитайте текст 2. “Inductance”, подчеркните во всех

предложениях подлежащее, сказуемое, определения. Укажите грамматическую модель каждого предложения. Назовите формальные признаки, по которым можно определить временные формы глагола-сказуемого.

 

TEXT 2. INDUCTANCE

In considering alternating current circuits, remember anytime current flows, a magnetic field surrounds the conductor. That flux (magnetic field) surrounding it is relative to the direction of current flow in the conductor. Since the alternating current circuit entails the alternation of the current flow first in one direction and then in another, the flux is also increasing and decreasing. As the current flow changes direction, the direction of the flux surrounding that conductor also changes.

In order to fully understand alternating current circuits we’ll consider certain other phenomena. The first of which we will term inductance. Inductance is the property of an electrical circuit which opposes the change of current. In an alternating current circuit both the current and the voltage alternate in magnitude and polarity (direction). Since the current and voltage alternate, the phenomenon of inductance retards the rate at which the current can change. It does not hinder the changing of the voltage. In a 60 (sixty) cycle system, if there is inductance in a circuit, the inductance actually retards and causes the current to lag behind the voltage sine wave.

In simple terms, the effect of inductance upon an AC circuit is that the inductance retards the current sine waves and causes them to lag behind the voltage sine waves. If there is no inductance in a circuit and it is purely resistive, the current and the voltage change at the same rate. They reach maximum at the same time and they reach zero at the same time. When inductance is introduced into a circuit, the inductance causes the current sine wave to lag behind that of the voltage sine wave. When inductance is introduced into a circuit, the current and the voltage do not rise to maximum at the same time, nor do they fall to zero at the same time. They peak and reach zero at different times. A complete cycle is said to be 360 electrical degrees.

The maximum amount that inductance can cause current to lag behind the voltage would be 90 (ninety) electrical degrees. This is evident in any electrical circuit where there is a large number of induction motors. A large size or number of induction motors, transformers, reactors or other equipment which introduces inductance into an electrical circuit causes the current to lag behind the voltage.

Any time the current and the voltage do not peak at the same time, there is a loss of efficiency. This means that it requires more current to do the same amount of work as would have previously been accomplished if the current and the voltage were both in phase. The efficiency of the equipment operation is less if the current and the voltage do not peak or reach zero at the same time.

Inductance in a direct current (DC) circuit is significant when there is a great increase or decrease of current flow in that circuit and upon energizing or de-energizing that circuit. When a DC system is de-energized rapidly the collapsing field in the DC circuit produces a very high induced voltage. This induced voltage is relative to the rate at which the lines force collapse and to the strength of the magnetic field. Actually this can be so great in magnitude as to “flash over” certain pieces of equipment. This induced voltage in a situation like this can be many times that of the normal circuit voltage. This may be evidenced on the opening of the generator field breakers.

Inductance of a circuit is measured in units of measurement termed “Henries”. A “Henry” is used to measure the inductance of a coil. Inductance can not be measured in ohms. A simple resistor can be checked with an ohmmeter. The inductance of a circuit is dependent on a number of factors. It is dependent upon the number of turns, the spacing between the turns, the shape of the coils, the diameter of the coil, the core material, the wire size, the number of layers of windings and the manner in which it is wound. Each of these things is involved in determining the inductance of a circuit. The calculation of the circuit inductance is something which is not ordinarily calculated by power operations personnel. However, inductance is a very important factor with regard to the operation of power systems. The operation of transformers is directly attributable to inductance.

Inductance is the ability to transfer power from one conductor to another conductor without a direct electrical connection. In a transformer, two conductors are wound around a common core. Because the flux is rapidly expanding at the rate of 60 cycles per second, inductance is present between the two coils. The secondary winding of the transformer has a voltage induced therein. If the secondary circuit is completed, current will flow.

Energy can be transferred from one circuit to the other by induction. This is commonly termed mutual induction. That is a transfer of power or voltage from one circuit to the other without a direct electrical connection. Self-inductance is another term which refers to the induction within one circuit.

 

4. Переведите следующие словосочетания на русский язык,

применяя правило “цепочки существительных”:

 

1) alternating current circuits

2) a current flow

3) a voltage sine wave

4) an induction motor

5) equipment operation

6) generator field breakers

7) the circuit voltage

8) the core material

9) the wire size

10) the circuit inductance

11) power operations personnel

12) power systems

 

5. Подберите русские эквиваленты к следующим английским

словам:.

 

1) field 2) flux 3) current 4) circuit 5) voltage 6) degree 7) equipment 8) magnitude 9) breaker 10) turn 11) core 12) winding 13) coil 14) conductor 15) transfer 1) амплитуда 2) сердечник 3) передача 4) поле 5) проводник 6) обмотка 7) оборудование 8) магнитный поток 9) виток 10) градус 11) напряжение 12) цепь, контур 13) выключатель, прерыватель 14) электрический ток 15) катушка

 

6. Найдите в тексте английские эквиваленты следующим русским

фразам:

 

1) при рассмотрении, рассматривая;

2) всякий раз, когда;

3) связан, соответствует, соотносится с;

3) для того, чтобы полностью понять;

4) фактически (действительно) замедляет, задерживает, тормозит;

5) проще говоря;

6) с одной и той же скоростью;

7) известно, что полный цикл составляет;

8) это означает, что;

9) требуется больше тока, чтобы;

10) измеряется в единицах;

11) ряд факторов;

12) то, что обычно не;

13) напрямую (прямо) приписывается, обусловлено;

14) поскольку поток быстро расширяется;

15) то есть передача.

 

7. Найдите в тексте информацию и расскажите о явлении

индуктивности и единицах ее измерения.

 

8. Переведите текст на русский язык.

УРОК 3. UNIT 3.

1. Прочитайте слова, обращая внимание на чтение подчеркнутых букв и

буквосочетаний.

Ref er, c er tain, c ir cuit, t ur n, th ir d, t er tiary, s er ve, comm er cial, p ur pose.

Pr e viously, betw ee n, f ie ld, m ean s, incr ea se, decr ea se, k ee p, m e tering,

ea sily.

Fl u x, cond u ctor, c u rrent, ind u ction, o ne, but, en ou gh, m u ch, n o thing.

Prev a lent, b a sis, ch a nge, gr ea t, a ble, s a me.

Compr i se, w i nding, beh i nd, l i kew i se, h i gh, wh y, pr i mary, c y cle, suppl y.

V i c i n i t y, cons i der, s i ngle, s i gn i f i cance, equ i pment, ab i l i t y, s y stem.

S our ce, m ore, c au se, c a ll, sm a ll, imp or tant.

Prod u ce, m u t u al, distrib u tion, n eu tral, val ue, u se, ind u ced.

R a pidly, b a nk, v a lue, cap a city, m a nner t a p.

Am ou nt, h ow, f ou nd, d ow n, n ow,r ou nd.

Des ire d, requi re d, h igher, w ire.

Reg ar d,ret ar d, f ar, ex a mple.

Transform er, whenev er, rel a tive, second a ry, a noth er, prop er ty.

 

2. Прочитайте и запомните следующие слова и словосочетания.

 

a bank – батарея;

losses – потери;

to step up – повышать (напряжение);

to step down – понижать (напряжение);

a transmission system – система передачи;

a tertiary winding – третичная обмотка;

an instrument transformer – измерительный трансформатор;

a current transformer – трансформатор тока;

a potential transformer – трансформатор напряжения;

a distribution transformer – трансформатор распределительной сети,

распределительный трансформатор;

a power transformer – мощный (силовой) трансформатор;

a one-to-one transformer – разделительный трансформатор с коэффициентом

трансформации, равным единице;

potential – электрический потенциал, разность потенциалов, напряжение;

metering equipment – измерительное оборудование, аппаратура;

relaying equipment – оборудование релейной защиты;

the primary – первичная обмотка;

the secondary – вторичная обмотка;

opposition – противофаза; сопротивление;

a stack – набор, комплект; блок, батарея;

capacitance – электрическая емкость; емкостное сопротивление;

resistance – (активное) сопротивление; сопротивление;

impedance – полное сопротивление;

billing – составление счетов; расчеты;

utilities – энергостанции (энергосистемы) общего пользования;

a tap changer – переключатель ответвлений (обмоток трансформатора);

 

a load tap changer – переключатель ответвлений (обмоток трансформатора)

под нагрузкой;

excitation – возбуждение; подмагничивание;

to shut down – остановить; выключить; отключить;

setting – уставка.

 

3. Прочитайте текст 3 “Transformers”. Во всех предложениях подчеркните

глагол-сказуемое. Укажите предложения, глагол-сказуемое которых 1) содержит модальные глаголы или их эквиваленты, 2) употребляется в страдательном залоге. Переведите эти предложения письменно.

 

TEXT 3. TRANSFORMERS

Part I

To understand the operation of a transformer, one must refer to certain basics which were previously explained. Voltage is produced whenever there is relative motion between a magnetic field and a conductor. Whenever current flows in a conductor, a magnetic field (flux) is established surrounding that conductor. The magnetic field (flux) is most prevalent in the vicinity of that conductor.

These basics are the basis for transformation of currents and voltages. A transformer may be defined as a piece of apparatus without continuously moving parts which by electromagnetic induction transforms alternating voltage and current in one winding into alternating voltage and current in one or more other windings, usually at different values of voltage and current. It consists essentially of an iron core on which are wound the primary and the secondary windings. The core comprises the means by which the flux is concentrated. The rapidly changing alternating current produces rapidly changing flux. As this flux increases and decreases, there is relative motion between flux from windings of the source side of the bank and the secondary windings. This produces mutual inductance. Mutual inductance is the ability to transfer energy from one circuit to the other circuit without a direct connection.

Transformers do not produce electricity. They merely transform it from one level to another. The total amount of power does not increase. There are losses which are associated with transformers. Anytime the voltage is stepped down, the current is stepped up by the same ratio. Likewise, when the voltage is stepped up, the current is stepped down by the same ratio. This is why transmission systems utilize high voltage. The higher the voltage the less the current for a given value of power. Less AC decreases losses.

The winding of a transformer which is electrically connected to the source of power is called the primary winding. The load side winding of a transformer is termed the secondary winding. Transformers with a third winding require a term other than primary and secondary. The third winding of a power transformer is termed the tertiary winding. A transformer may be used to step the voltage up or down. It may also serve to step the current up or down.

Let us consider the basic types of transformers. First, instrument transformers are of significance. Current transformers and potential transformers are instrument transformers. Instrument transformers transform potential or current to values which can be easily used on metering and relaying equipment. The potential transformer transforms voltage from a high value to a lower value, the most common of which is 120 volts AC. The potential transformer is similar to a power transformer, but can only handle small volt-ampere values. The load of a potential transformer must be considerably less than that normally found on a power transformer. A potential transformer will transform voltage. It can only handle enough current for metering and relaying.

Another type of instrument transformers is the current transformer. The current transformer transforms current from higher values to lower values. High values cannot easily be used in metering and relaying circuits. Low values may easily be used in metering and relaying circuits. The current transformer is rated in ratio of, for example 600:5. “MR” represents a multi-ratio current transformer. The “5” is not the maximum of current that can flow in the secondary, but is an easy reference to what is commonly referred to as a full scale deflection on an ammeter. Unlike a potential transformer a current transformer is a very low impedance device. The secondary of the current transformer offers very little opposition to the current flow. The primary may be the conductor and the secondary may represent a number of turns around that conductor. The current flow through the primary establishes flux. Based upon the number of turns, the secondary produces a current flow proportional to but much less than the primary current.

If the current is stepped down, the voltage must be stepped up. Anytime the current is stepped up, the voltage must be stepped down. The voltage is stepped down on a potential transformer and the current is stepped up. On a current transformer, the current is stepped down and the voltage is stepped up.

There is very little voltage associated with a CT secondary voltage. This is true because the primary of that current transformer is actually nothing more than one phase of the conductor itself. The voltage across two points on one phase of the primary is no more than millivolts.

 

4. Найдите в тексте эквиваленты следующих фраз, составьте с ними свои

предложения, описывая работу электрооборудования:

 

1) всякий раз, когда имеется;

2) всякий раз, когда ток течет;

3) состоит, по-существу из;

4) средства с помощью которых;

5) подобным же образом, когда напряжение;

6) вот почему системы передачи электроэнергии;

7) чем выше …, тем меньше;

8) он также может служить для того, чтобы;

9) могут легко использоваться;

10)должна быть значительно меньше (больше).

 

5. Назовите основные части трансформатора и расскажите о их

назначении.

 

6. Переведите текст на русский язык.

 

УРОК 4. UNIT 4.

1. Найдите в тексте примеры слов, в которых встречаются следующие

звуки и сочетания звуков:

/ Λ / an o ther, …, …, …;

/ ju: / distrib u tion, …, …, …;

/ з: / p ur pose, …, …, …;

/ i / s y stem, …, …, …;

/ ai / suppl ie s, …, …, …;

/ i: / ea sily, …, …, …;

/ ð / th ey, …, …, …;

/ ∫n / distribu tion, …, …, …;

 

2. Прочитайте и запомните следующие слова и словосочетания:

 

a lightning arrestor – грозовой разрядник;

lightning surges – грозовое (атмосферное) перенапряжение;

to extinguish the arc – гасить (погашать) дугу;

a surge crest voltage – максимальное импульсное напряжение; бросок

напряжения; максимальная величина перенапряжения;

to bypass – (зд.) отвести;

a surge discharge – разряд импульсного напряжения;

an outage – простой, перерыв; отключение, перерыв подачи

(электроэнергии); выход из строя;

a failure – отказ (в работе); авария; повреждение; неисправность;

a circuit breaker bushing – высоковольтный ввод выключателя;

to furnish a path – предоставить, обеспечить путь;

to cease to conduct – прекращать (останавливать); зд. не проводит;

rated voltage – номинальное (расчетное) напряжение;

an insurance – гарантия;

severity – интенсивность;

to break down – пробивать; выходить из строя;

to fail – повреждаться; отказывать в действии; выходить из строя; давать

перебои;

ratio – коэффициент трансформации.

 

3. Прочитайте текст 4. “Transformers”, Part 2. Найдите примеры глаголов-

сказуемых всех грамматических моделей. Укажите предложения, глагол-сказуемое в которых употребляется в сослагательном наклонении. Переведите эти предложения письменно.

 

TEXT 4. TRANSFORMERS

Part 2

Another type of transformer is the distribution transformer. A distribution transformer is a transformer with a capacity much less than the power transformer. It is normally used for the purpose of providing service to customers. We see distribution transformers on poles or on concrete pads for industrial or commercial application. They provide power for certain services in our systems.

The power transformer is considered a major transformer which is normally of a substantial capacity. A power transformer would be the definition assigned to the transformer which supplies power transforming voltage levels. The utility power transformer would be utilized to transform voltages from high voltage transmission levels to lower levels such as from 230 (two hundred and thirty) kV to 69 (sixty nine) kV or 115 (a hundred and fifteen) kV.

If the purpose of a transformer is to step the voltage down, it could be termed a step-down transformer. A step-down transformer is one that has a secondary voltage lower than the primary voltage.

A step-up transformer is used in conjunction with power generation equipment. After the power is generated, for example at a level of 13.8 (thirteen point eight) or 25 (twenty five) kV, it is stepped up to higher values which more easily permit transmission to distant locations with minimal losses. The power transformers that generation units utilize are of the step-up type.

Tap changers allow change of transformer ratio to give versatility required for utility system operation. Operating at low voltages is not desired. Operation at high voltage can result in over excitation of the transformer, increased noise levels, and greater excitation loss in terms of economics. Simply, it pays to operate at the best ratio for excitation conditions. Load tap changers allow for changing taps under full load conditions.

The type of tap changer which is also common is the “no load tap changer”. In order to operate this no load type, the transformer must be completely de-energized. It may be necessary to shut down, de-energize or change taps several times a year. If conditions remain stable, no changes may be required. As a general rule, voltage levels should be near the tap setting for the best economic considerations. It is possible; however, that other criteria may outweigh the economic considerations in arriving at a tap setting.

Lightning arrestors protect transformers from lightning surges. The purpose of lightning arrestors is similar to that of a safety valve on a boiler. The safety valve relieves a high pressure by permitting the escape of steam. When the pressure is reduced to normal, the valve closes and it is again ready to protect against another abnormal condition. Lightning arrestors operate in a similar manner. When a voltage much higher than normal voltage exists on a line, the arrestor immediately breaks down and furnishes a path to ground. As soon as the voltage returns to normal, the arc is extinguished, the arrestor ceases to conduct and the line returns to normal. Lightning arrestor equipment then must limit the surge crest voltage which may be applied to the apparatus it protects and bypass the surge to ground. The arrestor must be able to withstand its rated voltage and must be capable of extinguishing any power arc which follows the surge discharge.

Application of lightning protection equipment is an insurance against outages and equipment failure. ***The amount and kind of protection needed are influenced by the frequency and severity of storms in the area, the importance of reducing line outages due to lightning and the risk of failure of the equipment used. Generally, the insulation level of the line in the vicinity of the station, within the insulation level of the equipment in the station, should be considered in such a way that the line insulation would break down before the insulation in the station equipment would fail. Line insulators are cheaper and easier to replace than transformers and circuit breakers bushings.

 

4. Переведите следующие сочетания, обращая внимание на перевод

существительных и причастий в функции определения:

 

a distribution transformer the definition assigned to the transformer

a power transformer versatility required for the operation

power transmitting voltage levels increased noise levels

the utility power transformer the rated voltage

voltage transmission levels protection needed

a step-down transformer the equipment used

power generation equipment power provided for certain purposes

generation units the utility power transformer utilized to

utility system operation transform voltages

excitation conditions the power generated

load tap changers changes required

a no load type the apparatus applied

a lightning arrestor line insulators replaced

a lightning surge

a safety valve

lightning arrestor equipment

the surge crest voltage

the insulation level

the line insulation

 

5. Найдите в тексте английские эквиваленты следующих фраз:

 

1) он обычно используется с целью (в целях);

2) просто выгодно работать;

3) может возникнуть необходимость;

4) тем не менее, возможно;

5) как только напряжение возвращается;

6) в общем;

7) нужно, чтобы … выдерживал;

8) должен быть способен;

9) следует считать (учитывать).

 

6. Выберите из обеих частей текста “Transformers” информацию о разных

типах трансформаторов и расскажите о их назначении.

 

7. Расскажите о назначении защитного оборудования.

 

8. Переведите письменно предложение с ***. Переведите текст на

русский язык.

 

УРОК 5. UNIT 5.

1. Повторите правила чтения. Прочитайте следующие слова, обращая

внимание на чтение подчеркнутых сочетаний.

 

Des i gned, l i ne, t i me, t y pe, c y cle, f i ve, pr i marily, h y draulic, h i gh, i dentif ie d,

dev i ce, util i ze, w i nd, f i nd, l i ght.

Interr u pt, c u rrent, p u mping, n u mber, m u st, s u ch, d o ne, o ther, f u nction,

th o roughly.

Au tomatically, or der, c au se, dr aw, au xiliary, c au tion, rest ore, n or mal, m ore,

s our ce, c a lled, a lternating.

Thr ou gh, m o ve, r ou tine, l oo p, s oo ty, t wo, evol u tion, gr ou p, c oo led, r u le,

rem o val, m o vement.

C ir cuit, subm er sed, t er med, ref er, c er tain, w or k, em er gency, det er mine,

transf er, th er mal, conv er t.

Ar c, reg ar d, bl a st, p a ss, l ar ge, ar mature, ch ar ge, disch ar ge, ar ticle, h ar mful,

adv a ntage.

Circ ui t, e qu i pment, wh i ch, transm i ssion, d i str i bution, s y stem, capab i l i t y,

s i ngle, volt a ge, b e g i n, tr i p, unt i l, t y p i cal, cons i der, c y l i nder.

P ie ce, cont i nuous, m e tering, r ea ch, m ea ns, ea ch, th e se, rel ea se, rout i ne,

compl e te, h ea t.

C a pability, autom a tically, c a rrying, cap a city, d a mage, v a lue, g a s, v a cuum,

m a nner, disp a tch.

Distrib u tion, v iewe d, pn eu matic, u tilize, u se, c u bicle, prod u ce, s ui t, u nit,

f ew, f u el, u sually.

Break er, reclos er, typic a l, mod er n, medi u m, c o nsid er, vari ou s, o p e rat or,

c o ntin uou s, c o mpress or.

F ou nd, with ou t, n ow, h ow, ou t, all ow, ab ou t, ou tside, surr ou nd, am ou nt,

ar ou nd.

Br ea ker, m ay, r a ted, rel ay, th ey, b a sis, enc a sed, s a fety, b a sic, r ai se, d ay,

demonstr a te.

Cl o se, m o st, fl o w, contr o l, m ou ld, o pen, g oa l, h o me, l oa d, kn ow, bel ow,

c oa l, f o ld, bl ow.

Che ck, c lose, c ubi c le, brea k er, cir c uit, cy c le, c onfuse, c an, pneumati c,

c ontrol, c are, c apable c hemistry, ar ch ive, ar ch eology, s ch ool.

C ell, s pring, thi s, c ircuit, s afety, c ylinder, c ycle, s uit, re c eive, s earch,

sc ienti s t, sc ien c e, ne c e ss ary.

Whi ch, ch eck, swi tch ing, dis ch arge, combus tio n, ques tio n, na tu ral, su ch,

ea ch, ch ose.

Volta g e, dama g e, char g e, dischar g e, in j ury, ener g ize, emer g ency, g eneral,

sub j ect, lar g e, arran g e, ma j or, g enerate, sta g e, leaka g e.

Provi sion, deci sion, confu sion.

Mea sure, plea sure, u su ally.

W e, w ill, w ithin, wh ich, wh en, wh ere, wh y, w ith, o ne, wh ether, w ork,

wh ile, wh at, w ire, w ind.

S qu are, qu ick, qu arter, subse qu ent, qu ality, qu antity, qu estion, re qu ire,

conse qu ently, e qu ipment, ade qu ately, li qu id.

Th rough, th oroughly, th ink, th eory, th ermal, me th od, th ree, th irty,

ma th ematics, leng th.

Th is, th ey, wi th, wi th in, wi th out, th ereon, whe th er, al th ough, ano th er, th ere,

th at, th eir.

Fla sh, sh all, sh ould, ma ch ine, espe c ially, spe c ial, pre ss ure, effi c iency,

suffi c ient, accompli sh.

Applica tion, genera tion, ac tion, posi tion, loca tion, direc tion, men tion,

suc tion, fric tion.

Y es, y ou, y oke, y oung, y et, y ellow.

Wh o, wh ose, h ow, wh ole, wh om, h ello, H enry, h ere, h igh, h ydraulic, h ard.

Wr ite, wr ong, cu rr ent, ca rr ying, r elative, r ating, r ight, r ound, vi r us, t r ouble.

 

2. Прочитайте и запомните следующие слова и словосочетания:

 

a circuit breaker – автоматический выключатель;

fault current – ток повреждения, ток КЗ;

to be rated – быть расчитаным, определенным, запроектированным на;

a rating – характеристика, показатель, индекс, класс, расчетное значение,

номинальное значение, допустимое значение;

interruption – прерывание, разъединение, размыкание, разрыв;

to interrupt – прерывать, разрывать, размыкать;

a trip coil – катушка расцепления, катушка отключения;

a series trip coil – последовательно включенная катушка отключения;

a circuit recloser – выключатель с устройством повторного включения;

устройство АПВ;

a fault – повреждение, неисправность, короткое замыкание, КЗ,

to close – замыкать, включать,

an arc – (электрическая) дуга;

to be submersed – погружаться, быть погруженным;

an oil circuit breaker – масляный выключатель;

an air circuit breaker – воздушный автоматический выключатель;

an air blast circuit breaker – выключатель с воздушным дутьем;

a gas blast circuit breaker – выключатель с газовым дутьем;

a vacuum circuit breaker – вакуумный выключатель;

an operator – оператор, устройство управления;

a spring operator – пружинное устройство управления;

a motor operator – устройство управления с моторным приводом;

a closing coil – замыкающая катушка;

to trip – расцеплять, отключать;

a latch – релейный элемент, регистр-фиксатор, триггер-фиксатор, защелка,

запор;

a trip latch – отключающая, расцепляющая защелка;

an armature – якорь,

to charge – заряжать, подзаряжать;

to discharge – разгружать, снимать нагрузку, освобождать, разряжать,

выпускать, производить;

a cubicle – ячейка, шкаф, ящик;

a cell – элемент, ячейка, клетка;

a metal clad switch gear – распределительное устройство с металлическим

покрытием;

a flash suit – спецодежда;

switching – переключение, коммутация, выключение, прерывание,

разъединение;

emergency – авария;

a tank – бак;

a control valve – регулирующий клапан;

a piston – поршень;

a failure – отказ (в работе), авария, повреждение, неисправность;

to reset – повторно устанавливать, сбрасывать, восстанавливать, возвращать

в исходное положение или состояние;

 

3. Прочитайте текст 5 «Circuit Breakers», Part 1. Найдите в тексте

примеры на все грамматические модели. Выпишите предложения с глаголом- сказуемым, в состав которого входят модальные глаголы. Переведите эти предложения письменно.

 

CIRCUIT BREAKERS

Part 1

A circuit breaker is a piece of equipment which is designed to interrupt fault current automatically. Circuit breakers may be found on generation, pumping, transmission and distribution systems. Circuit breakers are rated in a number of ways: circuit breakers are rated in momentary and continuous current carrying capability. Breakers are also rated as to voltage, KVA and MVA, and interruption times.

The interruption time is the time from the point the current begins to flow through the trip coil (or the current value in the series trip coil of a current recloser reaches the trip value) until the breaker interrupts the fault. Closing time is a time between the point when closing is actuated and the circuit is closed through that breaker.

There are five basic types of circuit breakers used on power systems. They are the oil circuit breaker, the air circuit breaker, the gas blast circuit breaker and the vacuum circuit breaker. In each case the five terms designate the means which is used to interrupt the arc in the breaker. We will consider primarily the circuit breaker with applications of the air or magnetic air circuit breaker and the oil circuit breaker.

Circuit breakers are also identified by various means used to close them. A circuit breaker may be closed by a number of means. The device used to close a circuit breaker is called the operator. The various types of operators we might find on a power system could include the spring operator, the solenoid operator, the pneumatic operator, the hydraulic operator, the motor operator, and the neudraulic (hydropneumatic) operator. Each of these may be utilized in order to close a circuit breaker.

We should also consider the solenoid type operator, the spring type operator and the pneumatic operator. The solenoid type operator closes the circuit breaker merely by magnetic action produced by passing a large current flow through the closing coil. This causes the armature to close the circuit breaker in which position it is latched. If the trip latch is released it allows the breaker to trip. The spring type operator is one which utilizes an AC or DC motor to charge a closing spring. Most circuit breakers use a spring to assist in the tripping of the circuit breaker. The reference to a spring operator refers to the device used to close that circuit breaker. This is in addition to the spring used to trip the breaker. A DC motor is utilized to charge (wind) the spring, and the spring is used to close the circuit breaker. In closing, this large spring discharges and in closing the circuit breaker it latches it into position. As the circuit breaker closes it charges the tripping spring.

Breakers which have the spring operator must be checked upon drawing them out to be certain that this closing spring has discharged upon drawing the breaker from the cubicle or cell. In checking this closing spring, discharged when the breaker is open and drawn out of the cell, it is important to prevent personal injury to the personnel working thereon. Anytime switching is done on energized enclosed areas, such the cells of the metal clad switch gear, the flash suit should be worn for safety. Carelessness cannot be tolerated in any high voltage switching, whether routine or emergency applications are involved.

A pneumatic operator uses an air compressor, air storage tank, and a pneumatic cylinder to close a circuit breaker. A control valve allows air into the cylinder. The subsequent piston operation causes the operating rod to close the circuit breaker. The air is used to close the circuit breaker. Pneumatic operators are used on many types of oil circuit breakers. Do not confuse the operator type with the circuit breaker type.

All personnel should know how to trip a circuit breaker manually where that opportunity is provided in the event of an electrical trip failure. Know the location of the manual trip lever. If the breaker fails to trip electrically, then it would not trip

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