Transformer Design

Normally the winding which is designated to receive the input supply is termed as the “Primary” and the winding which in response to this input produces the required induced voltage as the output is termed as the “secondary” winding. Designing your own transformer as per a specific application can be interesting, but not feasible without calculating the various parameters typically involved with them.

The design procedure is followed assuming that following specifications of a transformer are given:-

Primary voltage (Vp)

Secondary voltage (Vs)

Secondar current (Is)

From these given details we calculate Tongue width, stack height, core type, window area as follows:-

Secondary Volt-Amps (SVA) = secondary voltage (Vs) * secondary current (Is)
Primary Volt-Amps (PVA) = Secondary Volt-Amps (SVA) / 0.9 (assuming efficiency of the transformer as 90%)
Turns ratio (n2/n1)= Secondary voltage(Vs)/Primary voltage (Vp)
Primary current (Ip) = Primary Volt-Amps(PVA)/ Primary voltage(Vp)
The require cross-sectional area of the core is given by:- Core area (CA) = 1.15 * sqrt (Primary Volt-amps(PVA))
Gross core area (GCA) = Core area(CA) * 1.1
The number of turns on the winding is decided by the ratio given as:- Turns per volt (Tpv) = 1/(4.44 * 10-4 * core area* frequency * flux density)
Winding data on Enameled copper wire (@ 200A/cm²) has to be obtained from tables

Making these calculations manually can be quite tedious. The software to do all the above calculations instantaneously can be downloaded by clicking the button below.

Once this zip file is downloaded you can unzip it and save the extracted files in a separate folder. To run the transformer design program double click the transformer.exe file. Enter the required data. The final result will show the number of turns for the primary and its thickness(s.w.g), the number of turns for the secondary winding and its thickness(s.w.g) and the lamination size. That's it!

Indian buyers can deposit Rs.500/- into my Punjab National Bank A/C No.0404000300340987 in favour of Robert P Minz, Ranchi at any of its branches in your city (linked by core banking) and inform me by email The program will be sent via email attachment in a zip file named