Deck 5: Single-Phase AC Generation Principles

Question 1

Most of the problems that occur with single-phase generators are from the ____________________, or the engine input, that drives the generator.

Answer 1

prime mover

Question 2

How is frequency measured?

Answer 2

Frequency is measured in hertz, or cycles per second.

Question 3

What is the significance of the number 120 in the formula used to determine the frequency of the generated waveform?

Answer 3

The number 120 is a constant used to convert RPM to revolutions per second, and pairs of magnetic poles to number of poles used in the formula.

Question 4

What three factors should be checked if the generator does not have correct output?

Question 5

If you multiply the ____________________ of the angle that the conductor moves from the horizontal starting point times the maximum induced voltage in the conductor, you can plot a graph of each induced voltage level at each angular position.

Question 6

The looped conductor multiplies the effects of the magnetic field cutting just one conductor.

Question 7

The equation associated with Faraday's law states that if 100 million lines of magnetic flux cut through a conductor in 1 second, then 1 volt is induced into the conductor.

Question 8

As the conductor passes directly under the center of the magnetic field pole, the flux is most dense and the induced voltage is greatest.

Question 9

If a conductor is spinning inside a(n) ____________________, then the conductor will pass through stronger and weaker magnetic fields in different directions.

Question 10

When a generator is used to produce a single sinewave output, it is referred to as a(n) ____________________ generator.

Question 11

Large power generation systems typically generate four phases at a time.

Question 12

The major source of electrical power in the generation of AC voltage is provided by electromagnetic generation.

Question 13

What three factors are needed for induction in electromagnetic induction-type generators?

Question 14

As the magnetic field moves past the conductor, the magnetic lines of force, called ____________________, pass through the conductor or cut the conductor.

Question 15

Calculate the frequency of a single-phase generator that has eight poles and spins at 600 RPM.