Inductance Calculation Toolbox
Formulas are from Wikipedia article on Inductance .
Straight single wire
***Check if correct. Why not depending linealy on length? *** What is limit towards infinite length?
| wire length: l = 100 mm | 100 mm |
| wire diameter: d = 1 mm | 1 mm |
| Low frequency inductance: | |
| L_DC = 100 nH/m * l * ( ln( l/(d/4) - 0.75) ) to nH | 59.895878 nH |
| High frequency inductance: | |
| L_DC = 100 nH/m * l * ( ln( l/(d/4) - 1) ) to nH | 59.889614 nH |
Pair of Parallel Wires
| Pair of Parallel Wires | |
| ====================== | |
| wire diameter: d = 1 mm | 1 mm |
| wire radius: r = d/2 | 0.5 mm |
| length: l = 100 mm | 100 mm |
| separation: s = 5 mm # must be >=2*r | 5 mm |
| L = 400 nH/m * l * ln( s/(2*r) + sqrt(s^2/(4*r^2)-1) ) to nH | 91.697267 nH |
Gate Current Oscillation Between Two SiC MOSFETs Chips
| Expression | Result |
|---|---|
| GS Loop between two chips | |
| ========================= | |
| Inductance: L = 30 nH | 30 nH |
| Capacitance: C = 5 nF / 2 | 2.5 nF |
| Resistance: R = 2 * 4 Ohm | 8 Ohm |
| Calculation of damping | |
| ====================== | |
| About RLC circuit see: | |
| https://en.wikipedia.org/wiki/RLC_circuit | |
| resonance angular frequency: omega0 = 1/sqrt(L*C) to MHz | 115.47005 MHz |
| attenuation: alpha = R/(2*L) to base | 1.3333333e8 1/s |
| damping factor: zeta = alpha/omega0 | 1.1547005 |
| ➔ it is slightly overcrictically damped, oscillation should not appear | |
| Open in Calcumber | |