For the circuit shown, design a load circuit (with the minimum number of R , L ,
ID: 1936396 • Letter: F
Question
For the circuit shown, design a load circuit (with the minimum number of R , L , C) that will draw the maximum average power P. Assume that the output impedance of the function generator is 50 Ohm. Calculate the maximum average power transferred to the load. Determine the apparent power |S|, reactive power Q. and the power factor pf associated with the load If the load is purely resistive, what will be the resistance of the load for maximum power transfer?Explanation / Answer
(a) Max power is transferred when load is complex conjugate of system resistance Therefore for Load Impedance,Zl = 50 - j*(2*pi*2.5*10^3*5*10^-3) => 50 - 78.54 j Resistance in Load,R = 50 ohm Capacitance in Load,C = 8.106*10^-7 F = 0.8106 micro Farad (b) I = V/(2*R) = 5/100 = 0.05 A P = I^2 * R = 0.125 Watt (c) Reactive power, Q = I^2 * 78.54 = 0.1964 VAR Apparent Power, S = sqrt(Q^2 + P^2) 0.2328 VA load impedance angle, theta = arctan (78.4/50) = 57.47 deg pf of load = cos(theta) = 0.538 , leading since load is capacitive (d) if load in only resistive , then value of load resistance for max power transfer Rmax = sqrt(50^2 + 78.54^2) = 93.105 ohm