I understand how it works, but I don't know how to get currents with magnitudes of amperes in the inductance.
what should I change?
You need to know three things:
First is the inductance (L)
Second is the peak current (I) you want to drive through the inductor.
Third is the highest frequency (f) with which you want to drive the inductor.
for example:
Suppose you want to drive a 1A Sinusoid through a 50mH inductor at 100Hz. This is how to calculate how much voltage you will have to apply to the inductor to make that happen.
X is the reactance of the inductor at 100Hz
X=2*pi*f*L = 6.28*100*0.05 = 31.45Ω
Ohm's law says that E=I*X, so E = 1A*31.45Ω = 31.45V
Here is a simulation of this example. Note that it confirms a zero-to-peak voltage V(a) of >31V is required to force 1A of current through a 50mH inductor at 100Hz:
That would require a power amplifier (with feedback around it to make it a voltage-controlled current-source) that can produce a Voltage of +-31.45V, at a current of +-1A. The LM675 is such a power opamp that will tolerate up to +-60V power supplies, and is capable of sourcing and sinking up to 3A.
Note that if you double the desired inductor current, you will have to double the applied voltage... If you double the frequency, you will have to double the applied voltage... If you double the inductance, you will have to double the applied voltage...