fly back converter thesis

hi all
am a fourth year electrical engineering student and am taking a fly back converter design as a thesis, can any 1 help me doin this thesis or supporting me by any papers, designs, thesis , guidelines to do the design or anything related to the topic specially am new to fly back converter.
thnx alllllllllllll:-|

Dear High voltage !
Hi
See below , please:
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Perhaps , those links can help you , or if you want i can introduce some books , to you .
Best Wishes
Goldsmith

more than enough dear gold smith...but am trying to find some thesis so i can compare my design with and also i need some papers with complete design and result plus i would be thankful if u introduce these books

and thnxx for helping..

regards

Well , these books are very easy , and suitable , and wonderful and delicious !!!! :
Switching power supply cookbook , by marty brown . and switching power supply design by , Abraham I pressman 3rd ed .( i learned many things from these books )
and thus below link can more help you :
https://www.edaboard.com/threads/229615/
Good luck
Goldsmith

The book Switchmode Power Supply Handbook (3rd edition) by Billings and Morey contains extensive discussion of the offline flyback, along with design examples and results. It talks about a broad range of power supply design topics, but gives special focus to the flyback.

Hi

power integration PI.com is good for flybakc they have somany models of flyback using diffarent switches for diffarent applications.

just visit the site u ll get all the information u need like design the parameters, transformer.,etc

thats really helped me soo much
thank u very much..

---------- Post added at 13:48 ---------- Previous post was at 13:31 ----------

one more question guys..!!

i am doing this thesis in tow sems, i am required to do the simulation of this topic using any software( multisim,ltc spise, Pspise...etc) in first sem and do the prototyping and building the circuit in PCB board in the sec sem..so my question is..is the calculation of secondary and primary winding, gapping the core, core selection and bobbin area necessarily for the circuit to be simulated or not..???

Use LTspice for simulating SMPS. It's pretty much built for that purpose.

As for transformer simulation, I'm not aware of a spice program that really deals with things like core loss and saturation without a decent amount of DIY coding. You will likely have to do transformer parameter calculation outside of spice, and then try to approximate it in spice with lumped elements. Linear parameters like leakage inductance and parasitic capacitance are simple to model. Core saturation may be modeled with a nonlinear inductor (I've made nonlinear inductors and they're not too bad, but I've never tried nonlinear coupled inductors... might be more challenging). Core loss probably can't be simulated in spice. Best way would probably be to do a simulation with no core losses, look at the current waveforms, calculate delta B, then calculate loss from that and subtract that from your simulated efficiency.

ahaa
i thought calculating the inductance of primary and secoundry will be enough to simulate the circuit.
thnx for ur help

---------- Post added at 16:32 ---------- Previous post was at 16:23 ----------

dear gold smith
is this the way to design fly back transformer..is it that easy??..can i use this calculation with a contrloller ic and get the mentioned output..??

---------- Post added at 16:34 ---------- Previous post was at 16:32 ----------

i mean this gold smith
https://www.edaboard.com/threads/229615/

Again Hello Dear High voltage .
You can use ,that way , to design the magnetic elements of each SMPS ( all topologies ) simply ! I have designed all of my SMPS magnetic elements with that way , until now successfully .

is it that easy??

Click to expand...

Isn't that easy ?!

Best Wishes
Goldsmith

yaaah it is..!!
okay iam going to take the same design u hv made to build a fly back converter (Vin=50..Vout=450 Vdc)..i will try to simulate it using Ltc3873-5 controller using ltspice software....any suggestion???

Honestly I have to recommend against using a sophisticated controller IC like the LTC3873-5, especially if this is your first time designing a flyback. I've used about a dozen of LT's controller ICs, and they can be very difficult to debug because their internal operation is so ambiguous. In particular, internal slope compensation means that you can never observe the true current ramp signal, which is very important. Also I'd recommend against using the "No Rsense" feature since it will just degrade the accuracy of your current control loop. For a thesis, you are probably going to be expected to explain the operation of the controller in detail, which means you probably don't want to use a black box whose exact internal workings aren't fully explained.

If I were you I'd go for a very basic unitrode controller which contains all the necessary elements of a controller, but doesn't hide anything from you. The UC3824 is my weapon of choice when making a supply which I want to have precise control of. The UC3843 is also good, though it doesn't have a soft start and its error amplifier has an internal reference connection. For simulation, these controllers can be built easily in LTspice using simple dependent sources, logic gates, etc, and I've done so several times in the past. And unlike LT's own models, when you build it yourself like that you can watch its internal operation.

good to know dear mtwieg
thnx

For simulation you can use the LT1242. It is available in LTSpice. It is very similar to the UC3842.

Hope this helps.
Tahmid.

ahaa
okay but how to calculate its (LT1242) resistors, capacitors and switches..

Follow the LT1242 datasheet and the UC3842 datasheet as well.

I have designed a flyback using the 3873 and modelled it in LTSPICE:
http://www.simonbramble.co.uk/dc_dc_converter_design/flyback_converter/flyback_converter_design.htm

And have written an LTSpice tutorial:
http://www.simonbramble.co.uk/lt_spice/ltspice_lt_spice.htm
This should help you master the basics...

where i can simulation for IC SG3524?????

thanks..