Transformer design worked example

[grim]

I am considering putting a step by step transformer design example on my website. It may help answer a few of the questions that come up on here.

As this forum contains my target audiance, and time is valuable, is this of interest?

 

[confounded]

I'm certainly interested.

 

[MrAl]

Hello there grim,


I think it would be a good idea, and you should provide a link so people here
can take a look. I also believe that you should provide links to sources for
materials such as transformer cores, wire, winding tape, etc., so that people
will know where to get the materials if they decide to build one up. Of course
the links should include places to get single piece quantities so hobbyists can
obtain what they need without having to buy the whole store.

 

[Chippie]

grim,

I think with your knowledge and experience it is a great idea and good of you to do this...

Many years ago I had a book that contained design info for transformers...I could do with it some times...

Would your design data cater just for iron cored tranformers or does it cater for toroidal types as well?

 

[grim]

I was thinking of a fully detailed 50VA design - the basic principles are the same for a 5va and a 500va. I will link to design data from various manufacturers, maybe with snap shots of designs for other VA ratings.

I willl look at toroidals later.

 

[Chippie]

I was thinking of a fully detailed 50VA design - the basic principles are the same for a 5va and a 500va. I will link to design data from various manufacturers, maybe with snap shots of designs for other VA ratings.

I willl look at toroidals later.

Excellent...

IIRC, the VA rating is based on cross sectional area of the core...how the number of turns for the primary( based on a 230v ac supply) are calculated is the bit that's missing for me..

I look forward to your tutorial..

 

[Hero999]

I think a helper spreadsheet would also be a good idea.

 

[grim]

i have looked at designing in Excel, as I currently use a program I wrote way back in the 90's. It runs on Datastar, which is a simple DOS database program, originally designed to run on an 8086 from a 5 1/4" disk.......

when we first ran it on the accounts department 286, everyone in the office was amazed how fast it computed. LESS THAN 30 SECONDS to do the design calculations!!!!

same program still runs on the latest chips, hiding away in the corner of my ram, and completes the same calculations in fractions of seconds.

thanks to dos2usb printer software, it lives on


what it isn't is a transformer design program though. it's more like a super programmable calculator, that a transformer designer can use to design with. Uses the same layout as the foolscap books I hand wrote my first designs in.

 

[MrAl]

Hi again grim,

As i said earlier, i think this would be very interesting.

What i dont think would be a good idea though is to provide all the equations
in Excel form, as many people dont have or even want that. Simple text
would be very nice.

If you dont write Windows software yourself i would be happy to write an
application for this project, a program that would reflect your design
criteria. I think it would be interesting.

I also hope that you can link to some sites were people could get the parts
required (wire, core material, etc.). Is that possible? Thanks.

 

[grim]

unless it's your job designing transformers, then calculating by hand will be fine.

the worked example will show where I get the data from to do the design, so other people can do their own.

it's really intended as more of a 'how do they design transformers' show and tell

Suppliers and data will of course be European, but the formulas and theories will work gloabally

 

[Hero999]

I prefer OpenOffice.org spreadsheet myself as it's totally protable and will work on any system but I understand that many Windows users who already have MS Office are probably happy with it and don't want to download another huge program just for some spreadsheet.

 

[blueroomelectronics]

Would Google Spreadsheet work? No software to install and updates would be a breeze.

 

[Hero999]

Google Speadsheet can save in OpenOffice and Excel format.

 

[MrAl]

Hello again,

Is anyone interested in a program that will utilize grim's formulae and provide
quick calculations?

 

[grim]

it's just some lookup tables, that look up the data an engineer would look up in catalogues and some pretty simple calcs. the worked example will show where to get the data and run through the calcs.

if you can handle V=IxR you can do this. damn, makes my job sound easy. lol

 

[Hero999]

I'd like that, it also be good if you released the source code.

 

[grim]

there isn't any source code, as i said before, DATASTAR is a database application that can perform very basic lookup and calculations.

I have been using it for 15 years, the folder contains the .com files, all my database definition files, all the data files and every design i have done in that time.


3.84mb

gotta love dos

 

[Hero999]

3.84MB is monstrous for a DOS application that isn't a game.

Most DOS programs tend to be under 1.44MB, one floppy disk.

 

[MrAl]

Well grim, shouldnt the data and calculation formulas be an a form that anyone
can read? What is this DATASTOR?

 

[grim]

3.84MB is monstrous for a DOS application that isn't a game.

Most DOS programs tend to be under 1.44MB, one floppy disk.

the .com file is 32k, it's the 15 years of records that have got it to this size..anway, i digress