### Author Topic: How to design a Coil Step By Step  (Read 3146 times)

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##### resonant charging chokes
« Reply #16 on: January 06, 2016, 15:07:04 pm »
res

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##### Voltage Intesifier Circuit
« Reply #17 on: January 06, 2016, 15:07:37 pm »
Vic

It works by charging the chokes and leting their field to collapse by making a secondary coil open the diode switch during pulse off..doubling the frequency of the applied voltage allowing to restrict the amps and allow voltage to go over and does the work in a dead short condition...

The relation of turns L2>Chokes allow the system to charge and collapse..

both chokes are in subtracting configuration with respect to the secondary...
« Last Edit: January 10, 2016, 12:37:19 pm by sebosfato »

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##### wave form
« Reply #18 on: January 06, 2016, 16:16:40 pm »
The wave form you input in the primary is basically the same as the output in a well coupled transformer

if you apply 12v pulse on a 1:1 transformer it will develop 1 amp at the secondary if a 12ohm load is connnected to it in short terms disconsidering losses... this 1 amp will be constant given its within the power handling of the transformer

the primary however will have a current that increases from 1 amp and on to keep the voltage constant at the output...

the current theoretically increase as a linear ramp for a inductor with lowe resistance to inductance ratio

in the case of the transformer as the load current will depend on the load impedance and translate it to the source with the transformation factor squared proportion.. also as load resistance change the primary current is affected too... for example a charging capacitor as load will not provide a linear ramp of current at the primary because at the start the capacitor seems like a short than it looks as open circuit as it reach the output voltage of the secondary

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##### Vic waveform
« Reply #19 on: January 06, 2016, 16:19:34 pm »
yes is to be scared hahaha

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##### Core carachterization
« Reply #20 on: January 10, 2016, 16:36:53 pm »
Principal parameters of cores are

Bmax  (Maximum flux density)
Crossection Area
Window (space for the coils and insulation)
Al (relates thepermeability of the core to the geometry, determines the inductance a coil will have for a number of turns of wire squared)
Gap
Magnetic path lenght

to determine the Al of a core make a coil with n turns measure the inductance and divide the measured value by n squared and you get the value of Al good to use for your measurement. Gap should be lowest or zero ... for toroids spread the turns over all the toroid as the gap is distributed in it... the more turns more precision.. but not too many turns are required... 10 or so is ok depending on core size... Al is normaly measured in nanoHenries or microhenries... the nucleus i have are 3000nH per turn squared

To find the Bmax of the core design a numbe of turns for a predetermined lower bmax say 0,100T and vary the voltage to see where the core saturates... getting the voltage where it saturated back to the equation will equate for the correct bmax of the core...

Common knowledge say Bmax of ferrite is 0,3T and silicon iron laminates 1,5T

Window will tell you the turns you can get into the core... for high voltage insulation a winding factor of 50% is assumed for some space is required for insulation...  from this you must aproximate from the 50% remain space to the maximum number of turns you can get for a particular wire diameter... assume the wire to be square so you dont get fooled by empty space among round wires... so the window remain in mm2 divided by the wire diameter also square so in mm2...  result is the number of turns.

When working with a core the lenth of the wire becomes less important than the turn numbers to get similar voltages is simple as getting the same number of turns regardless of the difference in diameter of the layer of the coil. Because the core closes the Bfluxaround the all coil.

« Last Edit: January 12, 2016, 01:09:59 am by sebosfato »

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##### more and more
« Reply #21 on: January 11, 2016, 02:05:32 am »