Vocabulary.

almost exclusively – почти исключительно

occasional­ly – иногда

to be wound – быть намотанным

at first glance – на первый взгляд

these of themselves – сами они

secondary consideration – вторичное значение

predetermine – предопределить

locality – местность

accommodate – разместить

circumference – окружность, окружение

obviously – очевидно

prohibit – запрещать

necessitate - делать необходимым, вынуждать

permit – разрешать

restriction – ограничение

5. Answer the questions.

1. What is the difference between the commutator and slip rings?

2. What does the number of poles depend on?

3. How can the dc generator be converted to an acgenerator?

4. What is a drum winding?

5. What types of winding do you know?

6. What are the advantages of the stationary armature over the rotating one?

7. What is required for the greater capacity of an alternator?

8. Give the definition of frequency.

9. What would a six-pole rotor require?

10. What are the two types of field construction used on alternators?

11. What type of alternators is the cylindrical rotor almost exclusively used for?

12. Where are the conductors of a cylindrical-pole winding placed in?

13. What determines the type of field construction to be used for a particular air generator?

14. When are steam turbines most efficient?

15. What may be the synonymous terms for high-speed and low-speed rotor and why?

6. Never looking into the text try to complete the following sentences:

By means of the commutator, the generated voltage in a dc generator is _____. Depending on the number of slip rings and the connection points on armature the number of poles _____ . If three slip rings are connected to points which are several electrical degrees apart, the result is _____ . The dc generator may be converted to_____. The armature of the alternator, like that of the dc generator, is also a _____ . The principles underlying armature construction are the same for both _____ . The stationary armature has very pronounced _____ over the rotating one. _____the slip rings from the shaft would present another problem. The high-voltage _____ required for the armature conductors is more easily accomplished on a stationary member. As more armature _____ is required for greater capacity, deeper _____ are also required. The number of cycles per second, or _____, is directly proportional to the _____ of the rotor. Coils of the same phase are usually connected in ____ in order to obtain the high voltages generated. The frequency in the armature conductors is directly proportional to the number of _____ . There are two types of field construction used on alternators: salient, or _____, and _____, or cylindrical pole. The conductors of a cylindrical-pole winding are placed in _____ which are parallel to the _____ . The major cost of operating a power plant or even an individual alternator lies in the _____ . Steam turbines are most efficient at _____, and therefore nearly all turboalternators are _____ machines. The terms high-speed and _____ rotors are sometimes used synonymously with _____ and salient-pole rotors respectively.