Quote
bobc
That is not how an inductor works. Flux is generated from the current. Even in an inductor, voltage generates the current. It does not just grow by itself.Quote
NoobMan
So again, its not a current sinusoid that is generated eslewhere than forced into the coil. Current just grows in the coil as result of playing with voltage, and that is the elemental law of the inducutor. Voltage across inductor builds the flux, to which the current is proportional. Now if you understand that, you will see previous statements differently and, even if most ppls dont see it, some other parts.
An inductor only generates current "by itself" when you remove the external voltage, and the flux collapses.
Please read again, what i said is this: "current just grows in the coil as result of playing with voltage". I didnt said the current "grows by itself", but as a result of "playing with voltage". E.g. voltage being applied. And if you read my entire post, you will see the reply was about uncle saying that stepper driver is making a current sinusoid and forces it into the coil. And in turn i said its the driver "plays with voltage", and hence the current is a result of the *driver* "playing with voltage".
When external voltage is removed, i would rather say that the energy stored in the inductor is released. I would say "released" instead, because e.g. "generated" might not be my choice of wording, but anyway something more or less like that - however my comment had nothing to do with this part.
As a result of driver putting the voltage across the inductor then inductor current grows to a value starting from zero and going up. Inductor *element law*: iL(t)=1/L*integral of vL(t)*dt. And current is proportional to flux, by some parts of maxwell eqs. But i would say that what "builds" the flux is the voltage rather than current. Because at moment time=0, the initial condition is iL(0)=0, this is what we are starting with. So only the voltage could build the flux, because the current is the output of the function, initially=0, and the input/variable is the integral of voltage over time. Again, because we are starting with initial condition iL(0)=0, and if we think current would be the one "building" the flux, then mathematically it would just sit at zero. This is why also as a choice of wording, i would rather say the "voltage builds the flux" and "current is proportional to flux". E.g. why "flux is generated from the current" would not be my first choice of wording either: i would rather say "flux its generated from voltage" instead, but thats just me and probably just semantics.
Beyond semantics, the very thing which depicts best the exact relation is the "element law" mentioned above, and if we put this up, then we can agree there is nothing we can argue about it - well, at least i wont argue about it. Thinking differently about it, and interpreting and expressing it differently this is ofc sort of normal, otherwise we would all be the same and that would be quite boring.