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welcome to my first video about inductors so
what's an inductor generally speaking and inductors a device that temporarily
stores energy
in the form of the magnetic field inductors are usually just quayle's wire
and one of the basic properties electromagnetism
is that when you have current flowing through a liar you create a small
magnetic field around it
soup equal up a lot of wire you'll get a stronger magnetic field
when current first starts to flow through the coil
and magnetic field stars to expand then stabilizers
and then you've got some energy stored in the magnetic field
when current stops flowing the magnetic field starts to collapse
and the magnetic energy gets turned back into electrical energy
so they're kind of like a temporary storage area for energy
you know how pastor store energy in the form of a static charge in resist sudden
changes in voltage
well inductors are very similar the store energy in the form of the magnetic
field
and resists certain changes in current and if you only learn one thing from
this video
remember the current in an inductor cannot instantly change
it always lags by certain amount of time now let me give you an example
normally when you connect a voltage source to load resistor
the current will be given by Ohm's Law in this case 10 bolts divided by twenty
owns gives you half a nap
and for this damn well I'm gonna be using the fifty percent duty cycle
square wave
so half the time you'll get .5 amps flowing and half the time there'll be no
current flowing
okay so here's the one killer hurts input squarely
in years the current waveform also perfectly square
now watch what happens when I had a $5 million re inductor in series with the
circuit
all of a sudden the square wave isn't so square anymore
there's a little bit of lag in the current and this is because it takes a
certain amount of time to store and release the energy in an inductor
now let's try that again with a higher input frequency of 10 killer
its now it's even more obvious that the inductors impeding the sudden changes in
current
this happens more and more as a race the frequency of the input way
at a hundred killer hurts
there is no square wave anymore it takes a longer time the store and release the
energy in the inductor
in the time it takes for the input wave to switch from high to low
so in this situation the inductor starting to average out the current
overtime
in this is very usefull it forms the basis of the LC low pass filters
which are covered in another video but just to give you a quick example
if I add a one thousand Mike repaired pastor just after the inductor here
I get a very clean DC output from a square wave input
and this is what good power supplies used to smooth out voltage
and to prove to you that all this happens because expanding and collapsing
magnetic fields
I'm gonna feed a square wave into the Sun shielded inductor here
and I'm going to use another inductor as a magnetic probe
so I can view any magnetic field changes on the oscilloscope
on top I have the input wave and on the bottom you can see the magnetic field
that I'm picking up
as I get closer to the inductor finally inductors have almost no effect on DC
they're basically just pieces wire with the resistance have a few millions
alright that's the basic somehow an inductor works
now I've got a couple more videos with more info on them and some practical
examples