Bulk power transmission

A transmission grid is a network of power stations, transmission circuits, and substations. Energy is usually transmitted within the grid with 3-phase alternating current (AC).

The capital cost of electric power stations is so high, and electric demand is so variable, that it is often cheaper to import some portion of the variable load than to generate it locally. Because nearby loads are often correlated (hot weather in the Southwest portion of the United States might cause many people there to turn on their air conditioners), imported electricity must often come from far away. Because of the irresistible economics of load balancing, transmission grids now span across countries and even large portions of continents. The web of interconnections between power producers and consumers ensures that power can flow even if one link is disabled.

XII. Составьте письменный реферат текста.

Unit 4

I. Определите значение данных слов и словосочетаний, используя англо-русский словарь.

power-line fuel-burning coal-fired corona discharge phase-shifting capacitance capacitor bank resistive to offset

inductance impedance fibre optic cable ground conductor common carrier pilot-wire utilities stand-alone reactive

II. Проверьте по словарю произношение данных интернациональных слов.

Corona, asynchronous, reactive, compensator, phase, factor, telecommunication, commercial, cable, structure.

III.Проанализируйте и переведите на русский язык следующие прилагательные, образованные с помощью следующих суффиксов.

-ant: significant, vacant, reluctant, redundant;

-ent: prominent, dependent, violent, frequent;

-able: controllable, reliable, available, variable;

-ous: asynchronous, onerous, ambitious, generous.

IV. Переведите следующие беспредложные терминологические словосочетания, состоящие из существительного, причастия I (герундия) и существительного, на русский язык.

fault-sensing protection relays fuel-burning power plants phase-shifting transformers

voltage regulating system load balancing economics

V. Переведите следующие терминологические словосочетания, состоящие из существительного, причастия II и существительного, на русский язык.

water-filled pipe

coal-fired power plants

pressure-operated switch

keyboard-controlled machine

VI. Переведите следующие беспредложные терминологические словосочетания, состоящие из существительных, на русский язык.

construction cost

ground conductor

power-line carrier

long-distance transmission

country and customer requirements

transmission line impedance

electric power transmission organization

VII. Переведите следующие предложения на русский язык, обращая внимание на разные значения словa since.

1) since — так как, поскольку (если since вводит придаточное предложение);

2) since — с (перед любыми словами и словосочетаниями, указывающими время);

3) since — с тех пор (часто в сочетании со словом then—since then)

1. Since the power flow through an HVDC (high voltage DC) link is directly controllable, HVDC links are sometimes used within a grid to stabilize the grid against control problems with the AC energy flow.

2. Since the unit of a potential is called a volt, potential itself is called “voltage”.

3. The process has been used since its first announcement.

4. Leased circuits from common carriers are not preferred since availability is not under control of the electric power transmission organization.

5. Whether the circumstances have been changed since then is not known.

VIII. Переведите следующие словосочетания с причастием II в функции определения на русский язык.

the fuels used to make that electricity

for a given amount of power transmitted

the percentage of energy lost

the Pacific Intertie located in the Western United States

IX. Переведите следующие предложения, обращая внимание на инфинитив в различных функциях.

1. It is necessary to transmit the electricity at high voltage to reduce the percentage of energy lost.

2.Today transmission-level voltages are usually considered to be 110 kV and above.

3. Utilities add capacitor banks and other components throughout the system to control reactive power flow for reduction of losses and stabilization of system voltage.

4. It is often cheaper to import some portion of the variable load than to generate it locally.

5. As a result, there is economic pressure to locate fuel-burning power plants near the population centers that they serve.

6. When electrical energy is required to be transmitted over very long distances, it can be more economical to transmit using direct current instead of alternating current.

7. Much analysis is done by transmission companies to determine the maximum reliable capacity of each line.

X. Переведите предложения на русский язык, обращая внимание на перевод страдательного залога.

1. Long-distance transmission is typically done with overhead lines at voltages of 110 to 765 kV.

2. At high AC voltages significant amounts of energy are lost due to corona discharge and the capacitance between phases.

3. Transmission lines can also be used to carry data: this is called power-line carrier, or PLC.

4. PLC signals can be easily received with a radio for the longwave range.

5. Sometimes a stand-alone cable is used, which is commonly fixed to the upper crossbar.

6. In that country transmission operations and market operations are controlled by separate companies.

XI. Выберите правильный перевод.

1. In remote areas a common carrier may not be available at all.	a) В отдаленных районах коммер­ческая сеть связи не может быть доступна всем. b) В отдаленных районах обыч­ная сеть связи может быть доступна не всем. c) В отдаленных районах коммер­ческая сеть связи мо­жет быть не доступна совсем.
2. Protection of the transmission line from short circuits and other faults is usually so critical that…	a) Защита линии передач от ко­роткого замыкания и других ошибок обычно так критична, что… b) Защита линии передач от ко­роткого замыкания и других неисправностей обычно на­столько необходима, что… c) Защита линии передач от ко­роткого замыкания и других неполадок обычно такая кри­тическая, что…
3. Transmission and distribution losses in the USA were estimated at 7.2% in 1995 …	a) В 1995 году в США потери при передаче и распростране­нии составили 7.2% … b) В 1995 году в США потери при передаче и распростране­нии оценивались в 7.2% … c) В 1995 году в США потери при передаче и распростране­нии были оценены на 7.2% …

XII. Выполните перевод всего текста.

Long-distance transmission

Long-distance transmission of electricity is almost always more expensive than the transportation of the fuels used to make that electricity. As a result, there is economic pressure to locate fuel-burning power plants near the population centers that they serve. The obvious exceptions are hydroelectric turbines - high-pressure water-filled pipes being more expensive than electric wires. The unvarying portion of the electric demand is known as the "base load", and is generally served best by facilities with low variable costs but high fixed costs, like nuclear or large coal-fired power plants.

Losses

It is necessary to transmit the electricity at high voltage to reduce the percentage of energy lost. For a given amount of power transmitted, a higher voltage reduces the current and thus the resistive losses in the conductor. Long-distance transmission is typically done with overhead lines at voltages of 110 to 765 kV. However, at extremely high voltages, more than 2 million volts between conductor and ground, corona discharge losses are so large as to offset the advantage of lower heating loss in the line conductors.

Transmission and distribution losses in the USA were estimated at 7.2% in 1995, and in the UK at 7.4% in 1998.

In an alternating current transmission line, the inductance and capacitance of the line conductors can be significant. The currents that flow in these components of transmission line impedance constitute reactive power, which transmits no energy to the load. Reactive current flow causes extra losses in the transmission circuit. The fraction of total energy flow (power) which is resistive (as opposed to reactive) power is the power factor. Utilities add capacitor banks and other components throughout the system - such as phase-shifting transformers, static VAr compensators, and flexible AC transmission systems (FACTS) - to control reactive power flow for reduction of losses and stabilization of system voltage.

HVDC

High voltage DC (HVDC) is used to transmit large amounts of power over long distances or for interconnections between asynchronous grids. When electrical energy is required to be transmitted over very long distances, it can be more economical to transmit using direct current instead of alternating current. For a long transmission line, the value of the smaller losses, and reduced construction cost of a DC line, can offset the additional cost of converter stations at each end of the line. Also, at high AC voltages significant amounts of energy are lost due to corona discharge, the capacitance between phases or, in the case of buried cables, between phases and the soil or water in which the cable is buried. Since the power flow through an HVDC link is directly controllable, HVDC links are sometimes used within a grid to stabilize the grid against control problems with the AC energy flow. One prominent example of such a transmission line is the Pacific Intertie located in the Western United States.

Grid exit

At the substations, transformers are again used to step the voltage down to a lower voltage for distribution to commercial and residential users. This distribution is accomplished with a combination of sub-transmission (33 kV to 115 kV, varying by country and customer requirements) and distribution (3.3 to 25 kV). Finally, at the point of use, the energy is transformed to low voltage (100 to 600 V, varying by country and customer requirements).

Communications

Operators of long transmission lines require reliable communications for control of the power grid and, often, associated generation and distribution facilities. Fault-sensing protection relays at each end of the line must communicate to monitor the flow of power into and out of the protected line section. Protection of the transmission line from short circuits and other faults is usually so critical that common carrier telecommunication is insufficiently reliable. In remote areas a common carrier may not be available at all. Communication systems associated with a transmission project may use:

• Microwaves

• Power line carrier

• Optical fibres.

Rarely, and for short distances, a utility will use pilot-wires strung along the transmission line path. Leased circuits from common carriers are not preferred since availability is not under control of the electric power transmission organization.

Transmission lines can also be used to carry data: this is called power-line carrier, or PLC. PLC signals can be easily received with a radio for the longwave range.

Sometimes there are also communications cables using the transmission line structures. These are generally fibre optic cables. They are often integrated in the ground (or earth) conductor. Sometimes a stand-alone cable is used, which is commonly fixed to the upper crossbar. On the EnBW system in Germany, the communication cable can be suspended from the ground (earth) conductor or strung as a stand-alone cable.

XIII. Составьте письменную аннотацию текста.

Unit 5

I. Определите значение данных слов и словосочетаний, используя англо-русский словарь.

monopoly commission agreement to operate to elevate cancer correlation the proximity of to devise

wireless onerous wholesale to beam rectenna to be fed satellite chairman

II. Проверьте по словарю произношение данных интернациональных слов.

Leukaemia, monopoly, radiation, voluntary, natural, standard, theory, problem, federal, regional, to demonstrate, business, operator, electromagnetic.

III. Определите способ словообразования следующих однокоренных слов и переведите их на русский язык.

1. to demonstrate — demonstrative — demonstrable — demonstration — demonstrator.

2. to establish — established — establishment.

3. to separate — separable — inseparable — inseparably — separate — separately — separation.

4. to operate — to cooperate — operational — operative — cooperative — operation — cooperation — operator.

5. to elevate — elevation — elevator.

IV.Проанализируйте и переведите на русский язык следующие существительные, образованные с помощью следующих суффиксов.

-ment: agreement, establishment, management;

-hood: childhood, brotherhood, motherhood;

-age: breakage, package, voltage, storage;

-ity: authority, electricity, capacity, density.

V. Расшифруйте следующие аббревиатуры и переведите их.

the USA	Independent Transmission System Operator
AC	Regional Transmission Organization
ISO	high voltage direct current
RTO	the Federal Energy Regulatory Commission
FACTS	Standard Market Design
MISO	the United States of America
FERC	alternating current
HVDC	Midwest Independent Transmission System Operator
DNA	flexible AC transmission systems
SMD	power-line carrier
PLC	deoxyribonucleic acid

VI. Переведите следующие терминологические словосочетания, состоящие из причастия I и существительного, на русский язык.

heating losses alternating current

superconducting cable controlling circuit

VII. Переведите следующие терминологические словосочетания. Помните, что в беспредложном терминологическом словосочетании главным словом является последнее, все слова, стоящие слева от него, играют второстепенную роль — роль определения. Перевод беспредложных терминологических словосочетаний надо начинать с главного слова.

solar power satellites

wireless power transmission

high load density areas

childhood leukaemia rates

wholesale electricity market operator

traction current converter plants

single phase traction power networks

VIII. Переведите следующие предложения на русский язык, обращая внимание на различие в значении слов other, another, the other.

1) other — другой, другие (какие-то, вообще); при самостоятельном употреблении имеет форму множественного числа others;

2) another — другой, еще один (всегда стоит перед существительным в единственном числе);

3) the other — другой, другие, все остальные (все те, которые остались); при самостоятельном употреблении имеет форму множественного числа the others.

1. One may use other methods.

2. Another method was tried.

3. The other methods were not useful.

4. Some studies support this theory, and others do not.

5. Another form of wireless power transmission has been studied for transmission of power from solar power satellites to the earth.

6. The current mainstream scientific view is that power lines are unlikely to pose an increased risk of cancer or other somatic diseases.

7. For the others the problem is more complicated.

IX. Переведите следующие предложения на русский язык, обращая внимание на различие в значении слова that.

1) тот, та, то — если that стоит перед существительным в единственном числе; указательное местоимение;

2) который — если that стоит после существительного; вводит определительное придаточное предложение;

3) то, что — если that стоит в начале предложения; вводит придаточное подлежащее;

4) что — если that стоит после сказуемого; вводит дополнительное придаточное предложение.

1. Regulatory Commission had issued a notice of proposed rulemaking setting out a proposed Standard Market Design (SMD) that would see the establishment of Regional Transmission Organizations (RTOs).

2. In that country transmission operations and market operations are controlled by separate companies.

3. Some have claimed that electromagnetic radiation from power lines elevates the risk of certain types of cancer.

4. The current mainstream scientific view is that power lines are unlikely to pose an increased risk of cancer or other somatic diseases.

5. That these decisions can be critical has been demonstrated by well-known scientists.

X. Переведите следующие предложения на русский язык, обращая внимание на различие в значении слова present.

1) present — a) присутствующий; b) настоящий, современный; c) имеющийся, данный;

2) to be present — присутствовать;

3) а present — подарок, презент;

4) to pre´sent — представлять, давать.

1. They were not present at the meeting.

2. The present situation is rather complicated.

3. In the present report we present the results of the simulation model.

4. It is argued by some that living near high voltage power lines presents a danger to animals and humans.

5. The project presented had many disadvantages.

6. What was your birthday present?

XI. Переведите следующие словосочетания с причастием II в функции определения на русский язык.

an increased risk of cancer

an unpopulated desert area

networks operated by the railways

equipment used at lower voltages

XII. Предложенный вариант перевода третьей части текста содержит ошибки. Найдите их и отредактируйте перевод.

Hidetsugu Yagi attempted to devise a system for wireless power transmission. Whilst he managed to demonstrate a proof of concept, the engineering problems proved to be more onerous than conventional systems. His work however, led to the invention of the yagi antenna. Another form of wireless power transmission has been studied for transmission of power from solar power satellites to the earth. A high power array of microwave transmitters would beam power to a rectenna in an unpopulated desert area. Formidable engineering, environmental, and economic problems face any solar power satellite project. There is a potential for the use of superconducting cable transmission in order to supply electricity to consumers, given that the waste is halved using this method. Such cables are particularly suited to high load density areas such as the business district of large cities, where purchase of a right of way for cables would be very costly.

Хидэцугу Йаги попытался изо­брести систему для беспроводной передачи энергии. Он сумел проде­монстрировать доказательство кон­цепции, но технические проблемы, оказалось, были более трудными, чем обычные системы. Его работа, однако, привела к изобретению ан­тенны Йаги. Другая форма беспроводной пе­редачи энергии была изучена для передачи энергии от солнечных спутников до земли. Мощный ис­точник электропитания микровол­новых передатчиков передавал бы электроэнергию к антенне со встро­енным выпрямителем в безлюдной области пустыни. Огромная разра­ботка, экологические, и экономиче­ские проблемы сталкиваются с лю­бым солнечным проектом спутника. Есть потенциал для использова­ния суперпроведения кабельной пе­редачи, чтобы поставлять электри­чество потребителям, при условии, что отходы сокращаются вдвое, ис­пользуя этот метод. Такие кабели особенно подходят высоко для об­ластей плотности груза типа дело­вого района больших городов, где закупка права пути для кабелей была бы очень дорогостоящая.

XIII. Выполните перевод всего текста.

Electricity market reform

Transmission is a natural monopoly and there are moves in many countries to separately regulate transmission. In the USA the Federal Energy Regulatory Commission had issued a notice of proposed rulemaking setting out a proposed Standard Market Design (SMD) that would see the establishment of Regional Transmission Organizations (RTOs). The first RTO in North America is the Midwest Independent Transmission System Operator (MISO). MISO's authority covers parts of the transmission grid in the United States midwest and one province of Canada (through a coordination agreement with Manitoba Hydro). MISO also operates the wholesale power market in the United States portion of this area.

In July 2005, the new FERC chairman, Joseph Kelliher announced the end of SMD efforts because "the rulemaking had been overtaken by the voluntary formation of RTOs and ISOs" according to FERC.

Spain was the first country to establish a Regional Transmission Organization. In that country transmission operations and market operations are controlled by separate companies. The transmission system operator is Red Electrica de Espana (REE) and the wholesale electricity market operator is Operador del Mercado Iberico de Energia - Polo Espanol, S.A. (OMEL). Spain's transmission system is interconnected with those of France, Portugal, and Morocco.