|
Given:
Ac source→Vrms=120V
Transformer ratio=5:1
Frequency=60Hz
Calculation:
Secondary Emf=Vrms*(turns ratio) ^-1=120/5
Secondary emf=V2=24V
V2(peak) =24*√2=33.9V
Let's take each diode's voltage drop=0.8v
And remember only two diodes are active in each cycle, So,
The output peak Voltage=33.9V-2(0.8) =32.3V
The output frequency=2*F(in) =2*60Hz=120Hz
Since, My Load=1kΩ ,
Load current=Vo/1kΩ= 32.3/1kΩ=32.3mA
The average dc output=Vo/π=10.28V
Now for the capacitor:
τ=RC, Since R=V/I and τ=1/f,
V(ripple) =I/fC;
I want a ripple of 1ΔV around, this will just give approximate value.
C=32.3mA÷(120*1V)
C=270μF
Notice that the ripple voltage is around 800mV to 1.5 V, this because of the exponential growth and we used an approximation
|
