When you put it like that its easy! Your awesome!
Now to calculate a suitable value of smoothing capacitor
C= i load / frequency x V
20/ (400x0.14)
0.357 F
Hey hey, its the first one you mentioned where it's considered to be equal to the ratio of the RMS ripple voltage to the DC component of the power supply output.
An aircraft electrical system operates at 115 volts at 400 hertz. It is to supply an average d.c. voltage of 28 volts and an average current of 20 A at a ripple factor of 0.005.
Determine: The r.m.s. ripple voltage
Here is my attempt.
Vc= Vs-2Vd
=28-2(0.7)
= 26.6 Volts
Vr= (1/2 x fs x C...