HW 2 Problem 19.1

There is some discussion in the 2010 posts about the sinusoidal approximation of v_s1(t) being multiplied by 1/2 because v_s(t) has a maximum value = V_g and minimum = 0, rather than the textbook example of +V_g and -V_g. A result of this scaling factor being that H(s) is also scaled. I don't think this is correct. The fundamental component of the Fourier series contains the amplitude term V_g ( (4*V_g/pi)*sin(w_s*t) ); that being the case, if V_g oscillates between V_g and 0 the sine wave will be accordingly 4*V_g/pi or 0. No need to scale. This will approximate the square wave. Does anyone else have some thoughts on this? Thanks.

HW 1 question 1

I've started looking at the HW and have viewed all the comments on the blog but am having trouble starting the HW. I don't remember solving differential equations of circuits in ECEN5797. Is there a section I could read in the book to brush up on this? Here is what I have right now. Could anyone give me a nudge in the right direction.
V-v(t)=Ldi(t)/dt and i(t)-I=Cdv(t)/dt

HW 1-1: Should V and I be considered step inputs at t=0?

HW 1-1: Should V and I be considered step inputs at t=0?
regards,
Nitish

HW-3(c)

Hi, all. For Q3(c), do you think it is assumed that Ds has the same I-V characteristics as D or not? Because if Ds is identical to D, then when D is on, Ds will shunt approximately the same amount of current as D. In that case, when Ms is on, the reverse recovery loss of Ds will be inevitable.

HW 1-1

Hi All,

It has been about 9 years since I took my circuits course and I'm struggling a little bit with this homework. I am getting i(t) and v(t) to be of the form X + Acos(wt) where X is a DC term and A is a constant. In order to find max values, I was thinking that taking the derivative and setting equal to zero is the right approach... Is this how anyone else approached the problem?

HW 1 Reverse Recovery in a boost converter

It is stated that "The diode remains forward biased... until the end of interval ta." Does this mean that all of the current through the diode during the tb interval should be considered to be stored in the diode junction and recovered during the next switching event?

HW1-1

Hi,

Regarding the HW1-1, the time domain differential equation:

I assumed the time domain function for i(t) is like I+A.exp(st) where A is a constant. I substituted this into the second order differential equation describing the i(t). However, the s values are imaginary and not including real part. It means that the i(t) is not damping. The inductor current should damp to I after long enough time. I cannot see the mistake I made in my approach. Should I assume any other solution for i(t) rather than the one mentioned above?

Would you please give me a hint on that.

Amin Z.

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