Lecture 61 EEE 302 Electrical Networks II Dr. Keith E. Holbert Summer 2001

Lecture 62 Maximum Average Power Transfer To obtain the maximum average power transfer to a load, the load impedance (Z L ) should be chosen equal to the complex conjugate of the Thevenin equivalent impedance representing the remainder of the network Z L = R L + j XL = R Th - j X Th = Z Th *

Lecture 63 Maximum Average Power Transfer V oc + - Z Th ZLZL Z L = Z Th * Note that ONLY the resistive component of the load dissipates power

Lecture 64 Max Power Xfer: Cases

Lecture 65 Class Examples Extension Exercise E9.5 Extension Exercise E9.6

Lecture 66 Effective or RMS Values Root-mean-square value (formula reads like the name: rms) For a sinusoid:I rms = I M /  2 –For example, AC household outlets are 120 Volts-rms

Lecture 67 Why RMS Values? The effective/rms current allows us to write average power expressions like those used in dc circuits (i.e., P=I²R), and that relation is really the basis for defining the rms value The average power (P) is

Lecture 68 Class Examples Extension Exercise E9.7 Extension Exercise E9.9 Extension Exercise E9.10