AC2 Fundamentals Unit 4 – Power in AC Circuits
Exercise 1 – Power Division
EXERCISE OBJECTIVE
When you have completed this exercise, you will be able to determine ac power division among
the components of an RLC circuit by using standard power formulas. You will verify your
results with an oscilloscope.
DISCUSSION
- Real power (PT) is drawn by resistive components and dissipated as heat.
- Reactive components draw apparent power (S) from the generator during one half-cycle and
supply reactive power (Q) during the second-half cycle. - Apparent power (S) is calculated using this equation: S = VGEN x I
where VGEN is the generator voltage (Vrms)
I is the circuit current (Irms) - Since the reactive components introduce a phase shift, apparent power will be greater than
the real power. - Total reactive power (QT) is the sum of the inductive component power minus the sum of the
capacitive component power.