Single-Layer Coil Inductance Calculator

The Formula

The formula for calculating the inductance of a single-layer coil is:

\[L = \frac{N^2 * r^2}{(9r + 10l)}\]

Where:

• L: Inductance (in Henries, H)
• N: Number of turns
• r: Radius of the coil (in meters, m)
• l: Length of the coil (in meters, m)

Calculation Steps

1. Convert the coil diameter and length from millimeters to meters
2. Calculate the radius by dividing the diameter by 2
3. Apply the formula to calculate the inductance
4. Convert the result from Henries to microhenries (µH) for easier reading

Example Calculation

Let's calculate the inductance for a coil with these parameters:

• Diameter: 20 mm (0.02 m)
• Length: 50 mm (0.05 m)
• Number of turns: 100

Applying the formula:

\[L = \frac{100^2 * (0.01)^2}{(9 * 0.01 + 10 * 0.05)} = 1.96 * 10^{-4} H = 196 µH\]

Limitations

This formula works best for coils where the length is greater than 0.8 times the diameter. For very short or very long coils, more complex formulas may be needed for accurate results.