Author Topic: Should I market this thing, and how?  (Read 16381 times)

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Offline amspire

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Re: Should I market this thing, and how?
« Reply #100 on: May 05, 2017, 03:12:12 am »
If you do not have transformers designed and tested, you do not have much. In designing small high efficiency designs, it is not uncommon to have many attempts at getting the transformer right, and it is usual to get results much poorer then expected. There is often signifigant losses in the transformer, and there is often more leakage inductance then expected. If you have to add snubbers to cope with the leakage inductance, you can easily find yourself below the 90% or even 80% efficiency level in spite of the great LTSpice numbers. Unless you design can actually somehow reabsorb and use the energy in the leakage inductance, it is energy that has to go somewhere.

The hardest part of switching supply design is the transformer design. You have variables of copper shape and cross section, wire insulation, core material, core gap, shape, winding arrangement, insulation gap between layers, former design and so on. If this is your first attempt, it will be much harder then you expect. High performance transformers are very imperfect devices and their design is a real art that can take years to master.

My design is not sensitive to leakage inductance -- actually, the more the better.
I'm using PL160 from CoilCraft, it is designed for 48V-72V input, but its rated Vs balance is okay for my application case.
Looks like you are using two transformers to get the 240W. It is an impressive transformer. You cannot make transformers yourself like that using off-the-shelf parts. The negative is you will be paying something like $15 for transformers from a single supplier and you will be competing against companies paying $2 for their single transformer.

It is a transformer that normally has 48V between primary and secondary, and you have to allow for something like 400V. I am assuming your supply can run off 240V mains. If it doesn't, I cannot see much of a market as a laptop supply. You will actually want to pull one of these transformers apart to see what the actual insulation between the windings consists of. It might be only a layer of enamel coating on the coils. I would be nervous about that for use with the mains.

The fact you do not care about leakage inductance is impressive. I am not going to ask you to reveal your design, so I will leave that to you. I assume you have added the extra leakage inductances into your LTSpice simulations.

Online mikeselectricstuff

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Re: Should I market this thing, and how?
« Reply #101 on: May 05, 2017, 08:48:31 am »
Efficiency numbers are based on simulation and calculation.
And  have mininmal credibility until you actually build & test it.
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