Time Domain to Phasor Domain (Linear Transformation) Sources 150 cos(377t + 20o) V 150 /20o V Resistors 20 20 /0o Inductors 50 mH (5010-3) /90o Capacitors 100 F 1/[ (10010-6)] /90o In a DC circuit, inductors act like a short circuit. In a DC circuit, capacitors act like an open circuit.
AC Circuits 1/(jC) = 20 /90o v(t) = 10 cos (200t + 10o) 10 /10o 40 mH v(t) = 10 cos (200t + 10o) 10 /10o Find i(t) jL = 8 /90o
AC Circuits 10.6 /90o v(t) = 50 V @ 60 Hz Find vc(t) 50 /0o 40 mH v(t) = 50 V @ 60 Hz Find vc(t) 50 /0o = 2 (60) = 377 rad/s 15.1 /90o
AC Circuits 500 /– 90o i(t) = 5 cos (2000t – 35o) 5 /– 35o 80 /90o Find v(t) and iL(t)
AC Circuits Find the equivalent (Thevenin) impedance at 1 kHz. = 2 (1000) = 6283 rad/s R = 20 /0o L1 = 12.57 /90o L2 = 6.28 /90o C = 0.159 /– 90o