Introduction to Electric Circuits

Chapter 11 AC Steady-State PowerPart 1

Electric Power

Effective Value

RMS value

Complex Power

Complex Power

Triangle

Conservation of Complex Power

Power Factor

0 :0 :

V I

V I

laggingleading

Power Transmission Model

Power Transmission Model

Correcting the Power Factor

Capacitive Compensating Impedance

power factor correction capacitor

power factor correction capacitor

MATLAB>> Vrms=10000>> I1=50000/Vrms>> S2=100000*exp(j*30.7*pi/180)>> I2=conj(S2/Vrms)I2 = 8.5985 - 5.1054i

>> I=I1+I2I = 13.599 - 5.1054i>> abs(I)ans = 14.525

>> S=Vrms*conj(I)S = 1.3599e+05 + 51054i

>> abs(S)ans = 1.4525e+05>> angle(S)*180/pians = 20.578

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