AC2 Fundamentals Unit 4 – Power in AC Circuits
An ideal capacitor or inductor does not convert energy to heat. The reactive component stores the
energy delivered to it from the generator (VGEN), then returns that energy to the circuit.
For one half-cycle of the generator's (VGEN) sine wave, the reactive component draws energy
from the generator.
During the other half-cycle, the reactive component returns power to the generator. The power
consumption of the reactive component exactly equals the amount of power returned to the
circuit.
Power not converted into another form of energy, such as heat, is called reactive power (Q).
Reactive power is the product of the voltage across and the current through a reactive
component. The unit for reactive power is the voltampere reactive (var). NOTE: The unit for real
power is the watt (W).
CAPACITOR DISCHARGERS MAGNETIC FIELD COLLAPSES