HW11 P2 resonant intervals

In problem 2 it seems like the resonant intervals should be intervals 3 and 5 only, not intervals 2, 3, 5, and 6 as stated in the problem. Anyone agree or disagree?

HW11, prob1

Hey,

Can anyone give me a hint to solve prob.1 on the homework. I am stuck with the selection of Vg.

HW11, pb 2

Hello All,

In pb 2, how steady-state value of clamped capacitor Vs be estimated ?
In forward converter, we can estimated as if it is operating as PWM.

However, on flyback, if I use the same procedure (PWM), I end up
with Vs equal to V/n, which is going to violate ZVS condition for Q2.

Thanks,
Tanto

Problem 3: Control to Output Transfer Function

I had a conceptual question that someone might be able to answer:

(1) Is the converter control-to-output TF just what is listed on page 300 for the boost converter? I think the parameters for the ZVS-QSW would be the same for the PWM parent converter only because d_hat is the control variable and not fs_hat (like in the one example posted for hw10).

(2) Can anyone explain why the 2 transistor ZVS-QSW is as simple as using the small signal model of the PWM boost converter? (This is on the last slide of the lecture 36).

HW10 P1

From class I got the impression that all converters of the same type follow the same state
plane analysis. I get a little confused when I compare the ZVS-QSW buck converter from class with the ZVS-QSW flyback in this problem. It looks to me like the behavior of the D_2 diode from the class example differs from that of the diode on the secondary of the flyback. In
the buck, when D_2 is conducting, it creates a short across the resonant capacitor so there is no voltage difference across the capacitor. In the flyback when the diode on the secondary is conducting and the transistors on the primary are not, then it seems you would still get a resonant circuit which completely changes the state plane diagram. Am I missing something here?

Hw10, pb2a

Hello,

Did anyone figure out how to solve part a yet ? I am trying to
figure out α - ς. My final equation for JL is:

JL = F/(2*π) * ( (1-μ) * (α - ς) * ( D/F + (1-μ)/μ * D )

where D = (α + ς)/(ωo.Ts)

Thanks

Problem 20.5 Verification

I was wondering if anyone got these numbers:

For 2.38A case: Cr <= 3.8nF and Lr < 6.81e-5 H
For 0.119A case: Cr < = 0.19nF and Lr < 1.37mH

So design: Cr = 0.19nF and Lr < 68.1 microH

n = 0.292

HW8 DCM equations derivation

Has anyone attempted the first question? Any hints on how to start?