Magnetics & Transformers Formulas
Magnetics & Transformers formulas cover Transformer EMF Equation, Transformer VA Rating, Transformer Voltage Regulation and more. These calculators let you solve for any unknown by entering the values you already know. Use them for quick design checks, study, and verifying real circuits.
Magnetics & Transformers Formula Calculators
- Transformer EMF Equation E = 4.44 · f · N · Bmax · A Frequency 5 Hz, Number of Turns 0.025, Peak Flux Density 10 G, Core Area 10 mm² → RMS Voltage = 5.55 nV
- Transformer VA Rating S = Vp × Ip = Vs × Is Winding Voltage 0.33 V, Winding Current 2 mA → Apparent Power = 0.66 mW
- Transformer Voltage Regulation VR = (Vnl − Vfl) / Vfl No-Load Voltage 0.33 V, Full-Load Voltage 0.726 V → Voltage Regulation = -0.5455 %
- Transformer Current Ratio Ip / Is = Ns / Np Secondary Current 4.4 mA, Primary Turns 0.025, Secondary Turns 0.055 → Primary Current = 9.68 mA
- Transformer Copper Loss Pcu = Ip² Rp + Is² Rs Primary Current 2 mA, Primary Resistance 1 Ω, Secondary Current 4.4 mA, Secondary Resistance 2.2 Ω → Copper Loss = 46.59 µW
- Transformer Iron (Core) Loss Piron = Physt + Peddy Hysteresis Loss 22 mW, Eddy-Current Loss 47 mW → Core Loss = 69 mW
- Transformer Turns-per-Volt TPV = 1 / (4.44 · f · Bmax · A) Frequency 5 Hz, Peak Flux Density 10 G, Core Area 10 mm² → Turns per Volt = 4.5 × 10⁶
- Transformer Impedance Matching Zin = (Np/Ns)² · Zload Primary Turns 0.025, Secondary Turns 0.055, Load Impedance 2.2 Ω → Reflected Impedance = 0.4545 Ω
- Magnetomotive Force (MMF) F = N × I Number of Turns 0.025, Current 2 mA → MMF = 5 × 10⁻⁵ A·t
- Magnetic Reluctance S = l / (µ0 · µr · A) Path Length 0.1 mm, Relative Permeability 0.025, Cross Section Area 10 mm² → Reluctance = 318.3 MA·t/Wb
- Hopkinson’s Law (Magnetic Ohm’s Law) Φ = F / S MMF 10 A·t, Reluctance 10 kA·t/Wb → Magnetic Flux = 1 mWb
- Magnetic Field Strength (H) H = N · I / l Number of Turns 0.025, Current 2 mA, Path Length 0.1 mm → Field Strength = 0.5 A/m
- Magnetic Coupling Coefficient k = M / √(L1 · L2) Mutual Inductance 100 nH, Inductance L1 0.22 µH, Inductance L2 0.47 µH → Coupling Coefficient = 0.311
- Inductance from Flux Linkage L = N · Φ / I Number of Turns 0.025, Flux per Turn 0.1 µWb, Current 2 mA → Inductance = 1.25 µH
Worked result for every Magnetics & Transformers formula
| Formula | Expression | Worked result |
|---|---|---|
| Transformer EMF Equation | E = 4.44 · f · N · Bmax · A | Frequency 5 Hz, Number of Turns 0.025, Peak Flux Density 10 G, Core Area 10 mm² → RMS Voltage = 5.55 nV |
| Transformer VA Rating | S = Vp × Ip = Vs × Is | Winding Voltage 0.33 V, Winding Current 2 mA → Apparent Power = 0.66 mW |
| Transformer Voltage Regulation | VR = (Vnl − Vfl) / Vfl | No-Load Voltage 0.33 V, Full-Load Voltage 0.726 V → Voltage Regulation = -0.5455 % |
| Transformer Current Ratio | Ip / Is = Ns / Np | Secondary Current 4.4 mA, Primary Turns 0.025, Secondary Turns 0.055 → Primary Current = 9.68 mA |
| Transformer Copper Loss | Pcu = Ip² Rp + Is² Rs | Primary Current 2 mA, Primary Resistance 1 Ω, Secondary Current 4.4 mA, Secondary Resistance 2.2 Ω → Copper Loss = 46.59 µW |
| Transformer Iron (Core) Loss | Piron = Physt + Peddy | Hysteresis Loss 22 mW, Eddy-Current Loss 47 mW → Core Loss = 69 mW |
| Transformer Turns-per-Volt | TPV = 1 / (4.44 · f · Bmax · A) | Frequency 5 Hz, Peak Flux Density 10 G, Core Area 10 mm² → Turns per Volt = 4.5 × 10⁶ |
| Transformer Impedance Matching | Zin = (Np/Ns)² · Zload | Primary Turns 0.025, Secondary Turns 0.055, Load Impedance 2.2 Ω → Reflected Impedance = 0.4545 Ω |
| Magnetomotive Force (MMF) | F = N × I | Number of Turns 0.025, Current 2 mA → MMF = 5 × 10⁻⁵ A·t |
| Magnetic Reluctance | S = l / (µ0 · µr · A) | Path Length 0.1 mm, Relative Permeability 0.025, Cross Section Area 10 mm² → Reluctance = 318.3 MA·t/Wb |
| Hopkinson’s Law (Magnetic Ohm’s Law) | Φ = F / S | MMF 10 A·t, Reluctance 10 kA·t/Wb → Magnetic Flux = 1 mWb |
| Magnetic Field Strength (H) | H = N · I / l | Number of Turns 0.025, Current 2 mA, Path Length 0.1 mm → Field Strength = 0.5 A/m |
| Magnetic Coupling Coefficient | k = M / √(L1 · L2) | Mutual Inductance 100 nH, Inductance L1 0.22 µH, Inductance L2 0.47 µH → Coupling Coefficient = 0.311 |
| Inductance from Flux Linkage | L = N · Φ / I | Number of Turns 0.025, Flux per Turn 0.1 µWb, Current 2 mA → Inductance = 1.25 µH |
Variables used across Magnetics & Transformers formulas
- E — RMS winding voltage (V)
- f — Supply frequency (Hz)
- N — Number of turns
- Bmax — Peak flux density in the core (T)
- A — Core cross-sectional area (m²)
- S — Apparent power (VA)
- V — Winding RMS voltage (V)
- I — Winding RMS current (A)
- VR — Voltage regulation (fraction or %)
- Vnl — Secondary voltage at no load (V)
- Vfl — Secondary voltage at full load (V)
- Ip — Primary current (A)
- Is — Secondary current (A)
- Np — Primary turns
- Ns — Secondary turns
- Pcu — Total copper loss (W)
- Ip, Is — Primary/secondary RMS currents (A)
- Rp, Rs — Primary/secondary winding resistances (Ω)
- Piron — Total core loss (W)
- Physt — Hysteresis loss (W)
- Peddy — Eddy-current loss (W)
- TPV — Turns per volt (turns/V)
- Zin — Impedance seen at the primary (Ω)
- Np, Ns — Primary/secondary turns
- Zload — Actual load impedance on the secondary (Ω)
- F — Magnetomotive force (ampere-turns)
- l — Magnetic path length (m)
- µr — Relative permeability of the material
- Φ — Magnetic flux (weber)
- H — Magnetic field strength (A/m)
- k — Coupling coefficient (0–1)
- M — Mutual inductance (H)
- L1, L2 — Self-inductances of the two coils (H)
- L — Inductance (H)
Questions people ask about Magnetics & Transformers
- Transformer emf equation online calculator — Transformer EMF Equation
- Transformer design turns per volt core area 39 cm2 50 hz — Transformer Turns-per-Volt
- How to calculate turns per volt for ei 48/16 core — Transformer Turns-per-Volt
- Coefficient of coupling formula calculator — Magnetic Coupling Coefficient
- Inductance from flux — Inductance from Flux Linkage
- Inductor flux linkage formula — Inductance from Flux Linkage
Related Formula Categories
Browse the full formulas index for all 32 categories.