Electrical Power Systems Technology

Alternating Current Power Systems 145

where:

Vi = the instantaneous induced voltage,

Vmax = the maximum induced voltage, and

θ = the angle of conductor rotation from the zero reference.

For example, at the 30° position (Figure 6-4), if the maximum voltage

is 100 volts, then

Vi = 100 V × sin θ

The sine of 30° = 0.5. Therefore:

Vi = 100 V × 0.5

= 50 volts

SINGLE-PHASE AC GENERATORS

Although much single-phase electrical power is used, particularly in

the home, very little electrical power is produced by single-phase alterna-

tors. The single-phase electrical power used in the home is usually devel-

Fig 6-4. Mathematic origin of an AC sine wave.