In the circuit, the voltage source frequency, amplitude and phase are 16 MHz, 42
ID: 2991198 • Letter: I
Question
In the circuit, the voltage source frequency, amplitude and phase are 16 MHz, 42 V and 1.5 rad correspondingly;
R1=7 kOhm, L1= 55 uH (u=micro), C1= 2.6 pF, R2=2 kOhm.
Find the average and reactive powers delivered by the voltage source into the circuit (ignore the signs).
Explanation / Answer
Given data is f=16MHz
V=42/_1.5 rad
R1=7k ohms
R2=2k ohms
L1=55uH
C1=2.6pF
XL1=2x?x16x10^6X58x10^-6=j5.5k ohms
XC1=[1/2x?x32x10^6X2.8x10^-12]=-j3.825k ohms
Now from the circuit R2 in series with -jXC1=(2-j3.825)k ohms ---(1) in parallel with jXL1
i.e (10.48-j4.26)k ohms ----(2) this is in series with 7k ohms resistance R1
Req=(17.406-j4.3) k ohms
Now total power S= V^2/Req= (42/_1.5)^2/[(17.406-j4.3)x10^3]
S=(-97.88-j9.8) kW =P+jQ
Active Power =P=97.88 kW
Average power=P/2=48.94kW
Reactive Power Q=9.8 kW