Isolated SEPIC converter design

[hellfish]

Isolated SEPIC converter

It's my first post here, so I'd like to say "hello" to everyone


I'm going to design the isolated SEPIC converter as my academic project. The biggest for me is to understand how inductors and transfomer work in this circuit and how to simulate it.

According to Erickson and Maksimovic "Fundamentals of Power Electronics" isolated SEPIC looks like the circuit in sep.jpg picture.

Does it mean that Lm inductance comes directly from transformer or should it exist in the circuit as a physical inductor? I think it should come from transfomer, but I'm not sure. And I'm also not sure how to simulate this circuit, excactly how to simulate SEPIC transformer. Should it be as in the circuit above or below in the picture septr.jpg?

Last question. Do you think it is possible and correct to use coupled inductor and transformer in the same circuit, as shown in the picture indcoup.jpg?

Thanks,
hellfish

 

[Chen Sol]

Hi hellfish. I am having the same dilemma. I don't know if Lm=L2 inductance comes directly from transformer or it is a physical inductor. I searched everywhere but I could not find an answer :-( But if you have got rid of doubts, could you please guide me? Thanks in advance!