POWER TRIANGLE
Basic AC Power
Figure 1 Power Triangle
The power triangle represents comparable values that can be used directly to find the efficiency
level of generated power to usable power, which is expressed as the power factor (discussed
later). Apparent power, reactive power, and true power can be calculated by using the DC
equivalent (RMS value) of the AC voltage and current components along with the power factor.
Apparent Power
Apparent power (S) is the power delivered to an electrical circuit. Equation (9-1) is a
mathematical representation of apparent power. The measurement of apparent power is in volt-
amperes (VA).
S = I2Z = ITE
(9-1)
where
S = apparent power (VA)
I = RMS current (A)
E = RMS voltage (V)
Z = impedance (W)
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