Tài liệu tiếng anh chuyên ngành hệ thống điện

Unit 1:
Engineering - what's it all about?
Task 1
List the main branches of engineering. Combine your list with others in your group. Then
read this text to find out how many of the branches listed are mentioned.
Engineering is largely a practical activity. It is about putting ideas into action. Civil
engineering is concerned with making bridges, roads, airports, etc. Mechanical
engineering deals with the design and manufacture of tools and machines. Electrical
engineering is about the generation and distribution of electricity and its many
applications. Electronic engineering is concerned with developing components and
equipment for communications, computing, and so on. Mechanical engineering includes
marine, automobile, aeronautical, heating and ventilating, and others. Electrical
engineering includes electricity generating, electrical installation, lighting, etc. Mining
and medical engineering belong partly to mechanical and partly to electrical.

Task 2
Complete the blanks in this diagram using information from the text.

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Reading Introduction
In your study and work, it is important to think about what you are going to read
before you read. This helps you to link old and new knowledge and to make guesses
about the meaning of the text. It is also important to have a clear purpose so that you
choose the best way to read. In this book, you will find tasks lo make you think before
you read and tasks to help you to have a clear purpose when you read.

Task 3
Study these illustrations. They show some of the areas in which engineers work. Can you
identify them? What kinds of engineers are concerned with these areas - electrical,

mechanical, or both?

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Task 4
Now read the following texts to check your answers to Task 3. Match each text to one of
the illustrations above.
Transport: Cars, trains, ships, and planes are all products of mechanical
engineering. Mechanical engineers are also involved in support services such as
roads, rail track, harbours, and bridges.
Food processing: Mechanical engineers design, develop, and make the machines
and the processing equipment for harvesting, preparing and preserving the foods
and drinks that fill the supermarkets.
Medical engineering: Body scanners, X-ray machines, life-support systems, and
other high-tech equipment result from mechanical and electrical engineers
combining with medical experts to convert ideas into life-saving and preserving
products.
Building services: Electrical engineers provide all the services we need in our
homes and places of work, including lighting, heating, ventilation, airconditioning, refrigeration, and lifts.
Energy and power: Electrical engineers are concerned with the production and
distribution of electricity to homes, offices, industry, hospitals, colleges and
schools, and the installation and maintenance of the equipment involved in these
processes.
Language study deals with/is concerned with
What is the link between column A and column B?
A

B

mechanical

machines

electrical

electricity

Column A lists a branch of engineering or a type of engineer. Column B lists things
they are concerned with. We can show the link between them in a number of ways:
1 Mechanical engineering deals with machines.
2 Mechanical engineers deal with machines.
3 Mechanical engineering is concerned with machines.
4 Mechanical engineers are concerned with machines.
5 Machines are the concern of mechanical engineers.

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Task 5:
Match each item in column A with an appropriate item from column B and link the
two in a sentence.
A

B

1 marine

a

air-conditioning

2 aeronautical

b

roads and bridges

3 heating and ventilating

c

body scanners

4 electricity generating

d

cables and switchgear

5 automobile

e

communications and equipment

6 civil

f

ships

7 electronic

g

planes

8 electrical installation

h

cars and trucks

9 medical

i

power stations

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Task 6: Writing
Fill in the gaps in the following description of the different branches of engineering using
information from this diagram and language you have studied in this unit.

The main branches of engineering are civil, 1 ……….., 2 ……….., and electronic.
Mechanical engineering is 3…………., 4 ………….machinery of all kinds. This branch
of engineering includes 5 …………., automobile. 6……….,and heating and ventilating.

The first three are concerned with transport: 7………. cars and planes. The last 8………
with air-conditioning, refrigeration, etc
Electrical engineering deals with 9………… from generation to use. Electricity generating
is concerned with 10…………. stations. Electrical installation deals 11 ………….. cables,
switchgear. and connecting up electrical equipment.
Two branches of engineering include both 12…………and 13………… engineers. These
are mining and 14………… engineering. The former deals with mines and mining
equipment, the latter with hospital 15 ……….. of all kinds.

Unit 2:

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Unit 3: Graphs

In engineering, graphs and charts are a common way of giving information. They
allow a great deal of data to be presented easily in visual form.

Task 1

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Task 2
Study the graph opposite which shows typical daily load curves for a power station,
Answer these questions about the graph for weekdays
1. When is the peak load?
2. When is there least demand?
3. When is the load 65% of capacity?
4. What is the load at 1 p.m.?
Describe changes in load for these periods:
5. Between 6 a.m. and 10 a.m.
6. Between 7 p.m. and midnight.
7. Between 3 p.m. and 5 p.m.
Language study Describing graphs
Look at the period 6 a.m. to 10 a.m. We can describe the change in load in two ways:
1 The load rises.
2 There is a rise in load.
We can make our description more accurate like this:
3 The load rises sharply.
4 There is a sharp rise in load.
Study this table of verbs and related nouns of change. The past form of irregular verbs is

given in brackets.
Direction
Verb
Up
climb
go up (went up)
increase
rise (rose)
Down
decline
decrease
dip
drop
fall (fell)
go down (went
down)
Level
not change
remain constant

Noun
increase
rise
decline
decrease
dip
drop
fall
No change
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These adjectives and adverbs are used to describe the rate of change:
Adjective

Adverb

slight

slightly

gradual

gradually

steady

steadily

steep

steeply

sharp

sharply

sudden

suddenly

fast.

fast

Task 3
Study this graph which shows the load at weekends.

Write sentences to describe the load during these periods.
1 Saturday, 8 a.m. to noon.
2 Saturday, 6 p.m. to ] 0 p.m.
3 Saturday, noon to 5 p.m.
4 Saturday, noon to 1 p.m.
5 Sunday, 2 a.m. to 8 a.m.
6 Sunday. 8 a.m. to 9 a.m.
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7 Sunday, noon to 3 p.m.
8 Sunday, S p.m. to 10 p.m.

Task 4:
Look at Fig. 1 and Fig. 2. Make comparisons of these periods. For example:
Sunday, 4 a.m. to 8 a.m./weekdays at the same time.
On Sunday the load remains constant between 4 a.m. and 8 a.m. but on weekdays it
rises sharply.
1. Sunday, noon to 3 p.m./Saturday at the same time.
2. Weekdays. 10 p.m. to 1] p.m./Saturday at the same time.
3. Saturday peak load/Sunday peak load.
4. Sunday, noon to 1 p.m./the rest of the week at the same time.

Word study Common verbs in engineering
Study this list of common verbs in engineering which you have studied in this book.
They all have the sense of 'make something happen'.
lower

make low

raise

make high

heat

make hot

release

make free

compress

make smaller volume

reduce

make smaller

increase

make larger

Task 5
Fill in the blanks in these sentences with suitable verbs from the list above.
1 When thermoplastics are ……………., they soften.
2 If a gas is……………..it heats up.
3 Refrigeration preserves food by……………..its temperature.
4 A heater……………..the temperature of the water.
5 The rising piston……………..the fuel mixture.
6 Designers try to……………..the weight of a structure.
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7 When the push button is……………..the valve spring pushes up the spool.
8 Pumping fluid into the main cylinder gradually……………..the jack.
9 Aerodynamic designs……………..wind resistance.
10 The motor starts up slowly, then gradually……………..speed
11 At intermediate substations, power is ……………..to 11 kV for light industry
12 When the child……………..the handle, the seat swings back under the weight.
Writing Describing a graph
An important mechanical test of a metal is the tensile test to destruction. Increasing
loads are applied to a specimen of the metal until it breaks. For a mild steel specimen,
a graph of load against extension looks like this:

Task 6
The following sentences describe the most important stages of the test. With the help of
the graph:
graph.

put the stages in the correct sequence to form a text describing the

-

fill in the missing references (0, P, E, Y, U, F).

a From …………to ……….the specimen extends in direct proportion to the load
applied.
b This rapid extension continues until point…………….., the maximum load, is
reached.
c From……………..there is a rapid increase in length for each increase in load.
d At……………..the specimen finally fractures.
e After……………..the specimen lengthens further but the load falls.
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f Soon after P the material reaches its elastic limit, marked on the graph as
point……………...

Task 7
Add this extra information to your text.
a Up to the elastic limit, the steel will regain its original length when the load is removed.
b Up to U there is no change in the cross-section of the steel.
c After the elastic limit, the steel will not regain its original length.
d After U the specimen undergoes 'waisting'.
e Y is the yield point.

Task 8
Refer to each of these figures at an appropriate place in your text. Use expressions such as these:
As shown in Figure A. See Figure A. (Figure A)

Technical reading Properties and applications of carbon steels

Task 9
Study the diagram below which shows how tensile strength, hardness, and ductility vary
with the percentage of carbon in carbon steels. Answer these questions:
1 What percentage of carbon gives the greatest tensile strength?
2 What happens to ductility between 0.08% and 0.87% carbon?
3 How does increased carbon affect hardness?
4 What is the effect on tensile strength of increasing carbon beyond 0.84%?
5 What happens to ductility beyond 0.87% carbon?

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Task 10
Now study the diagram below for extra information and answer these questions.
1 What is high carbon steel?
2 How much carbon docs tool steel contain?
3 Compare the properties of mild steel and hard steel.
4 What kind of steel is tin plate made from?
5 What kind of steel arc car springs made from?

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Unit 4: Con Edison
I

READING AND COMPREHENSION

Con Edison - A bit of background on a complex field

Many players figure in New York City's electricity system. The most visible player is Con
Edison, which supplies most of the electricity the city uses and serves Westchester County, too.
Since the industry was deregulated, Con Edison delivers electricity through its immense
5 transmission and distribution system to the 3.2 million customers in its 690-square-mile service
area. (Among other statistics: Con Edison's 93,000 miles of underground cable could circle the
Earth 3.6 times; it has 36,000 miles of overhead cable.) Electricity not generated locally is
imported via transmission lines that come in from New Jersey, from Long Island, and from the
northeast and Canada through Westchester County.
10 Conceptually, Con Edison's system looks like this:

Fig.1-1. Con Edison’s system outline

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As its name suggests, "Consolidated Edison" was formed through consolidation of many small
power generation companies. Today, history is reversing itself: clean "distributed generation" is
coming into favor, as the substantial benefits of a decentralized system come to be appreciated
and as new technologies facilitate it. Con Edison defines distributed generation as a facility
producing up to 20 MW of electricity dedicated to the support of nearby associated load. Con
Edison's portfolio includes electric and natural gas delivery, as well as steam delivery through the
largest district steam system in the world.
20 Among other players are these:

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•

The Public Service Commission regulates retail electric, gas, and steam utilities.

•

The New York State Research & Development Authority (NYSERDA) promotes
energy efficiency, R&D, and environmental goals. It provided $2 million to Verdant
Power's project in New York.

•

The Independent System Operator (a.k.a. the New York Power Pool) operates the
state's high-voltage electric transmission system and administers the state's wholesale
energy markets.

•

The Federal Energy Regulatory Commission (FERC) regulates interstate transmission
of electricity and licenses hydropower projects.

•

The New York Power Authority sells electricity to the city government and other parties
and owns and operates several electric generation plants.

The Economic Development Corporation's quarterly Energy and Telecom News is a good
source of information on developments in this complex, dynamic field. The Mayor's Energy
35 Policy Task Force 2004 report, "New York City Energy Policy: An Electricity Resource
Roadmap," provides a good overview of the city's current and future energy needs and its
strategy for meeting them.

Task 1

Rephrasing

Rewrite the following sentences, replacing the words in italics with expressions from the
passage which have similar meanings:
1. The most visible player is Con Edison, which provides most of the electricity the city uses
and serves Westchester County, too.
2. Con Edison distributes electricity through its immense transmission and distribution
system to the 3.2 million customers in its 690-square-mile service area..
3. As its name implies, "Consolidated Edison" was formed through consolidation of many
small power generation companies.
4. The Independent System Operator (a.k.a. the New York Power Pool) operates the state's
high-voltage electric transmission network and administers the state's wholesale energy
markets.

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5. The New York Power Authority sells electricity to the city government and other parties
and owns and operates several electric generation stations.

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Task 2

Contextual reference

What do the pronouns in italics in these sentences refer to?
1. Since the industry was deregulated, Con Edison delivers electricity through its immense
transmission and distribution system to the 3.2 million customers in its 690-square-mile
service area. (line 5 & 6)
(a)The industry’s; immense transmission and distribution system’s
(b)Con Edison’s; immense transmission and distribution system’s
(c)Con Edison’s; Con Edison’s
(d)The industry’s; Con Edison’s
2. As its name suggests, "Consolidated Edison" was formed through consolidation of many small
power generation companies. (line 12)
(a)Con Edison’s system
(b)Consolidated Edison
(c)Consolidation
(d)Power generation company
3. Today, history is reversing itself: clean "distributed generation" is coming into favor, as the
substantial benefits of a decentralized system come to be appreciated and as new technologies
facilitate it. (line 15)
(a)Consolidated Edison
(b)History
(c)Distributed generation
(d)Decentralized system
4. It provided $2 million to Verdant Power's project in New York. (line 24)
(a)NYSERDA
(b)Energy efficiency
(c)R&D
(d)Environmental goal
5. The Mayor's Energy Policy Task Force 2004 report, "New York City Energy Policy: An
Electricity Resource Roadmap," provides a good overview of the city's current and future
energy needs and its strategy for meeting them. (line 37)
(a)The Mayor’s; the city’s current and future energy needs

(b)New York City Energy Policy’s; energy needs
(c)Overview’s; future energy needs
(d)New York City’s; the city’s current and future energy needs

Task 3

Checking facts and ideas

Decide if these statements are true or false. Quote from the passage to support your decisions.
1. Only Con Edison figures in New York City's electricity system.
2. Con Edison supplies most of the electricity the city uses and serves Westchester County, too.
3. Con Edison imports electricity from New Jersey, from Long Island, and from the northeast
and Canada through Westchester County.
4. Con Edison defines distributed generation as a facility producing 20 MW of electricity
dedicated to the support of nearby associated load.
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5. Con Edison provides services of electric and natural gas delivery, as well as steam delivery
through the largest district steam system in the world.
6. Public Service Commission and NYSERDA are parts of Con Edison.
7. Verdant Power's project in New York is funded by NYSERDA.
8. The state's high-voltage electric transmission system is operated by the Independent System
Operator.
9. The function of FERC is to only license hydropower projects.
10. The New York Power Authority owns and operates several electric generation plants.
II

USE OF LANGUAGE

Task 4

Relative clauses 1

Study these sentences:
1. The most visible player is Con Edison.
2. Con Edison supplies most of the electricity the city uses and serves Westchester County, too.
Both these sentences refer to Con Edison. We can link them by making sentence 2 a relative
clause.
1+2. The most visible player is Con Edison, WHICH supplies most of the electricity the city
uses and serves Westchester County, too.
The relative clause is in CAPITALS. Note that Con Edison in sentence 2 becomes WHICH.
Study these other pairs of sentences and note how they are linked:
3. Consumers are supplied at higher voltages than domestic consumers.
4. These consumers use large quantities of energy.
3+4. Consumers WHO USE LARGE QUANTITIES OF ENERGY are supplied at higher
voltages than domestic consumers.
5. 33kV lines are fed to intermediate substations.
6. In the intermediate substations the voltage is stepped down to 11kV.
5+6. 33kV lines are fed to intermediate substations WHERE THE VOLTAGE IS STEPPED
DOWN TO 11kV.
Now link these sentences by using a suitable relative clause:
1. Energy is vital to New Yorkers' lives and to New York City
New York City is the financial, corporate, and communications capital of the United States,
as well as a leading world destination for business and tourism.
2. The investments and improvements are necessary to meet growing energy demand
The energy demand has increased more than 20 percent during the past 10 years.
3. For the summer of 2007, the company forecasts a peak load of 13,575 megawatts for its
service area.
The peak load for its service area includes a peak of 11,780 megawatts for New York City

and 1,795 megawatts for Westchester County

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4. Workers require illumination of 300 lux.
The workers install heavy machinery.
5. In 1982, the first hydro-electric plant was built in the United States.
The first hydro-electric made use of a fast flowing river for generating electricity.
6. The large consumers should be supplied stable voltage
The large consumers use a large quantities of electricity.
7. Dams are constructed to create artificial water storage areas at the most convenient locations.
Dams control the water flow rate to the power station turbines.
8. Francis turbines are the most common water turbine in use today.
The Francis turbine was developed by James B. Francis.
9. An electric motor is a machine for converting electrical energy into mechanical energy.
The electric motors can be run on direct (dc) or alternating current (ac).
10. Hydroelectric power now supplies 20% of world electricity .
The hydroelectric powers use the kinetic, or movement energy of rivers.

Task 5

Pronoun links between sentences

When we link sentences together, or into paragraphs, repeated nouns usually become pronouns.
EXAMPLES

1. A short circuit occurs in a generator.
2. The short circuit may cause large current.
3. The large current may damage the equipment.

When a short circuit occurs in a generator, it may cause large current. This may damage the
equipment.
Note: When there may be misunderstanding, or when the repeated noun comes a long time after
its first mention, the full noun is used.
EXAMPLES

Power system electricians install and maintain high voltage electrical power distribution
equipment, including generators and transformers in generating stations or powerhouses. They

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inspect and test installed electrical equipment at power houses and major substations. They repair
or replace faulty electrical equipment and complete test and maintenance reports.
Compare this version where the full nouns have been kept:
Power system electricians install and maintain high voltage electrical power distribution
equipment, including generators and transformers in generating stations or powerhouses. The
power system electricians inspect and test installed electrical equipment at power houses and
major substations. The power system electricians repair or replace faulty electrical equipment and
complete test and maintenance reports.
Now replace the repeated nouns in following paragraph with suitable pronouns where there is no
likelihood of confusion.
Investor-owned electric utilities are privately owned entities. The investor-owned electric utilities
represent 8 percent of the total number of electric utilities and approximately 75 percent of
electric utility generating capability, generation, sales, and revenue in the United States. Like all
private businesses, investor-owned electric utilities have the fundamental objective of producing
a return for investor-owned electric utilities’ investors. These utilities either distribute profits to
stockholders as dividends or reinvest the profits. Investor-owned electric utilities are granted
service monopolies in certain geographic areas and are obliged to serve all consumers. As
franchised monopolies, these utilities are regulated and required to charge reasonable prices, to

charge comparable prices to similar classifications of consumers, and to give consumers access to
services under similar conditions. Most investor-owned electric utilities are operating companies
that provide basic services for the generation, transmission, and distribution of electricity. The
majority of investor-owned utilities perform all three functions. The investor-owned electric
utilities operate in all States except Nebraska, where electric utilities consist primarily of
municipal systems and public power districts.

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