| A (Parameter) | B (Value) | C (Formula / Unit) | |---------------|-----------|--------------------| | Vp (V) | 230 | Input | | Vs (V) | 12 | Input | | f (Hz) | 50 | Input | | Ae (cm²) | 5.2 | Input | | Bmax (T) | 1.2 | Input | | | =B2/(4.44*B4*B5*B3*0.0001) → ~830 | turns | | N ratio | =B2/B3 → 19.17 | - | | Ns | =B9/B10 → 43 | turns (add 1–2 turns) | | Primary I (A) | 0.48 | Input or from VA | | Secondary I | 4.0 | Input | | Wire Pri (mm²)| =B12/B6 → 0.16 mm² | assume J=3 A/mm² | | Wire Sec (mm²)| =B13/B6 → 1.33 mm² | - |
(especially for small transformers).
| A | B | C | D | E | F | G | |---|---|---|---|---|---|---| | | Value | Unit | Formula | Result | Check | Status | | Core Area | 12.0 | cm² | - | - | - | - | | Flux Density | 1.2 | T | - | - | - | - | | Turns/Volt | - | - | =1/(4.44 50 B2 B1 0.0001) | 3.12 | - | - | | Pri Turns | 718 | - | =230 B4 | 718 | - | - | | Sec Turns | 37 | - | =12 B4 | 37 | - | - | | Pri Wire (mm²) | 0.21 | mm² | =VA/230/2.5 | 0.21 | SWG=25 | OK | | Window Fill | 38% | % | =Copper_area/Window_area | 0.38 | <0.4 | OK | transformer design calculation excel
Designing a transformer calculation sheet is not merely an exercise in data entry; it is an exercise in structured programming without code. A well-designed spreadsheet follows a distinct logic flow: . | A (Parameter) | B (Value) | C
The most critical cell in your Excel workbook is based on this equation: The most critical cell in your Excel workbook
VAVp×ηthe fraction with numerator cap V cap A and denominator cap V sub p cross eta end-fraction Usually taken as for air-cooled transformers. Required Wire Area:
: Once the TPV is set, Excel automatically multiplies it by the primary and secondary voltages to tell the engineer exactly how many loops of wire to wind. The Muscle: Wire Gauges and Window Space Now the "skeleton" needs "muscle"—the copper wire.