I got some inductances, and I just built a very simple RL (series) circuit.
The goal is to do a basic measure of real inductance.
L = 1mH (axial resistor-like inductance).
R = 100 ohm
Connected as:
voltage source --- resistor --- inductor --- ground
Approach:
A perfect voltage divider would happend when reactance equals 100 ohm. Right?
f = 100 / (1e-3 * 2 * pi) = 16 kHz
Simulation:
Peak-peak voltage across each element match. Current lags voltage.
Yellow : source voltage.
Blue: inductor voltage
Red: resistor voltage.
Real world:
1.- voltage on each element match at a much lower frequency (9.6k vs 16k).
2.- peak-peak voltage is not source/sqrt(2), but much lower (40% vs 70%).
I tried with 1 kOhm and 2 kOhm resistors too.
It seems that the gap between theoretical/real frequency narrows as R gets bigger.
It makes me think that the inductor has somekind of internal series resistance, but it seems far to big (I would hope to find something like 5 ohm ESR)
My multimeter measures 0.9 mH (within 10% tolerance).
I must admit this is all I can get.
Could anyone briefly explain what am I missing?
The goal is to do a basic measure of real inductance.
L = 1mH (axial resistor-like inductance).
R = 100 ohm
Connected as:
voltage source --- resistor --- inductor --- ground
Approach:
A perfect voltage divider would happend when reactance equals 100 ohm. Right?
f = 100 / (1e-3 * 2 * pi) = 16 kHz
Simulation:
Peak-peak voltage across each element match. Current lags voltage.
Yellow : source voltage.
Blue: inductor voltage
Red: resistor voltage.
Real world:
1.- voltage on each element match at a much lower frequency (9.6k vs 16k).
2.- peak-peak voltage is not source/sqrt(2), but much lower (40% vs 70%).
I tried with 1 kOhm and 2 kOhm resistors too.
It seems that the gap between theoretical/real frequency narrows as R gets bigger.
It makes me think that the inductor has somekind of internal series resistance, but it seems far to big (I would hope to find something like 5 ohm ESR)
My multimeter measures 0.9 mH (within 10% tolerance).
I must admit this is all I can get.
Could anyone briefly explain what am I missing?