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Hey there,
I don't really know if it is the right place to ask my question, on the edaboard forum, they told me to come here, so I'm trying my luck.
So... I'm French and I'm seeking help for a school project. I chose to work on metal detectors based on inductance change. What I have to do is very basic science : I need to have a bit of theory and then carry out an experiment to illustrate the theory.
What I've done so far :
Experiment :
I did a pass-band filter powered by a function generator set on the resonant frequency. When I approached several metals next to the coil, I notice that the output voltage diminished (because I wasn't on the resonant frequency anymore).
As the resonant frequency is 1/2*sqrtLC, my experiment showed that the inductance changed !
Theory : (or where the problems begin)
I was told to consider my metal as a loop ... with R2 its resistance and L2 its self inductance. So I was wondering to what extent can we consider a metal as a loop with a current passing through ?
My coil is a made of N loops of wire.
The two are coupled by a mutual inductance M.
So I did what I was told I calculated what is called the "visible inductance", which is confirming my experiment.
Do you think it is okay ?
I have another problem, I really need some theory explaning the influence of permeability on my inductance change. I googled the topic but I can't find anything satisfactory. Can you help me on this ?
It says that I can't add images
so I've put two pictures on this website so that you can understand better what I'm trying to do !
Thank you sooo much for your help and sorry for the english mistakes !
I don't really know if it is the right place to ask my question, on the edaboard forum, they told me to come here, so I'm trying my luck.
So... I'm French and I'm seeking help for a school project. I chose to work on metal detectors based on inductance change. What I have to do is very basic science : I need to have a bit of theory and then carry out an experiment to illustrate the theory.
What I've done so far :
Experiment :
I did a pass-band filter powered by a function generator set on the resonant frequency. When I approached several metals next to the coil, I notice that the output voltage diminished (because I wasn't on the resonant frequency anymore).
As the resonant frequency is 1/2*sqrtLC, my experiment showed that the inductance changed !
Theory : (or where the problems begin)
I was told to consider my metal as a loop ... with R2 its resistance and L2 its self inductance. So I was wondering to what extent can we consider a metal as a loop with a current passing through ?
My coil is a made of N loops of wire.
The two are coupled by a mutual inductance M.
So I did what I was told I calculated what is called the "visible inductance", which is confirming my experiment.
Do you think it is okay ?
I have another problem, I really need some theory explaning the influence of permeability on my inductance change. I googled the topic but I can't find anything satisfactory. Can you help me on this ?
It says that I can't add images
so I've put two pictures on this website so that you can understand better what I'm trying to do ! Thank you sooo much for your help and sorry for the english mistakes !
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