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Induction heating- using MOSFETS

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tdilip

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induction heating circuit

My final year UG project is "Automation of Induction Furnace" . I saw a circuit on net with Two MOSFETS half bridge inverter circuit to heat the coil ..the frequency is 209khz i=100A . I am mechanical student from india and i can'nt find the stated high rated MOSFETS... are the MOSFETS for this purpose are costly and rear?WHat is the complete circuit for this purpose.. is it complex?
https://www.richieburnett.co.uk/indheat.html
https://www.richieburnett.co.uk/lclr.gif --the circuit

is there any simple way of producing induction heat... the temperature produced can be less... (do'nt mind even if it is as low as 50 centigrade.) i just want a small model for induction heat...any good samaritan over there please help me..please....please....
 

induction heater circuit

No body there to help??
 

    V

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    conexy

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    stanislas

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half bridge induction heater

Thank you IAN..
can u please give any links /info about conecting MOSFETS/IGBTS ...... does pcb required for this purpose.... does it require any expertise... i do'nt know anything till now about MOSFTES/IGBTS

lclr.gif

https://www.richieburnett.co.uk/lclr.gif
I want to design the above circuit but do'nt have any knowledge what will be the complete circuit for above circuit.....(its dumbe to ask this...but i feel i can get answer at this forum..thanks you)

what i basically want is to produce a high frequency AC with resonance matching inductor and a tank capacitor
what will be the gate driver circuit for this application.... i am a total dumb in electronics and i will be very gald for any sort of help.....
 

    V

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induction heating mosfet

Take a look at the picture below ..
It shows an example of Half-Bridge circuit driven by high speed driver ..
To make it working you will need to add a simple, adjustable frequency square wave generator ..
If you can, register with Maxim-IC.com and ask them for free samples of the following ICs:
MAX038 - adjustable generator
MAX5062/5064 - half-bridge driver

Regards,
IanP
 

lclr induction heater

Hi Dilip

A few questions and suggestions as below:-

1) what depth are you looking for :- If I am correct 209Khz will still give you skin effect as used for surface hardening. It is still near RF induction heating range. If you are looking for deeper heating as for forging application you have to go to medium frequency range. And for MF you have to have different circuit as Tank circuit components will become very large. This is similar to any inverter circuit.

From my experience even if you can generate the frequency with desired power you still require skill to transfer the power efficiently to load and see the heat.

2) As your project name suggest you are looking for automation of Induction heating. For this application and with your mechanical background you can demo your project with 50 Hz heating. Many forging companies are using it. This is less efficient but you can show all the desired results. Please check bearing induction heaters.


Please let me know if you need any information. Sorry for any mistake above.

Regards
 
induction heating circuits

..Thanks alot Mr.Ian for your instant help and great support
....i am very glad to reach this forum
Mr. AVM_Noida -you got me right....what i want is ---to demonestrate induction heat,use a thermocouple to sense the temperature send it to a PLC(using Labview then plot a graph).....then if the temperature is more than stipulated range the PLC adjusts the current / so as to maintain it in the range.... this is my project in brief
I searched on net for induction heating and got the above circuit - i tried for given MOSFET numbers in KOLKata-- but can'nt find,now i learned from Ian that the driver circuit need some more ..in total i find it is complex...
In simple i want induction heat which builds up heat soon(in five/six minutes) and temperature reached is not of much importance... it will be great if it is more::|
So Avm please give details of a simple induction heater as much as you can....thank you once again AVM and Ian
 
simple induction heating circuit

Hi Dilip Kumar

This what I found on the net. A simple circuit using transistors.

**broken link removed**

I will post again if I get more information.

Thanks
 

lclr resonance tank

I am not sure if you have come across this site but I think you will find a lot of interesting info on induction heating ..
A conceptual MOSFET self resonant oscillator
This design is a result of small scale experimentation. I originally wanted to use SCRs because of the simplicity of the design. But it turns out that low cost, readily available SCRs do not handle a frequency high enough to heat small crucibles full of metal, nothing above 10KHz. My application induction of heating requires frequencies between 200kHz and 1Mhz. So I turned to MOSFET devices and a self resonant circuit made the most sense.
https://www.dansworkshop.com/Induction Heating.shtml

Regards,
IanP
 

    V

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induction heater mosfet

Why not use Thyristor?

I am use AD116 from EUPEC for induction heating

:D :D
 

    V

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mosfet induction heater

MOSFET and IGBT are the expensive components. You can use the high speed thyristor/triac, much cheaper, which parts depends on your local market.

nguyennam
 
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    adrisa

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induction heater driver circuit

Be advised that the resonant capacitor will have to carry the 100A current you suggested you want in your coil. Industrial induction heaters use expensive water cooled caps, like those made by Celem. For a homebrew unit, you can parallel a number of polypropelyne caps and keep watch on how hot they get.

Your coil will heat with 100A, too. Again, industrial units use water cooled copper tubing. If you operate in tens to hundreds of KHz, you should get less heating from litz wire compared to covventional wire.

Be careful to keep the frequency at resonance if you use a parallel resoant tank output. This can draw huge currents if you arent careful. Series resonance avoids this.

I would suggest you use a magnetic iron or steel sample to heat, as the hysteresis losses in the piece will help you gain coupling effieciency, compared to just eddy current heating. This should translate into lower current requirements in your coil. But don't get red hot with it- once you pass the Curie temperature, the loading on your circuit will change drastically and could easily destroy it.

If your expertise is on the mechanical side, I know that some early induction heating units physically rotated a permanent magnet to get the changing magnetic field. If you don't need a lot of heat, you might get this to work, slowing the rotation (motor) way down to reduce heat.
 
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    lw1ecp

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Re: induction heating mosfet

Take a look at the picture below ..
It shows an example of Half-Bridge circuit driven by high speed driver ..
To make it working you will need to add a simple, adjustable frequency square wave generator ..
If you can, register with Maxim-IC.com and ask them for free samples of the following ICs:
MAX038 - adjustable generator
MAX5062/5064 - half-bridge driver

Regards,
IanP

Hey, what values should you choose for the above circuit, the caps and the resistors mainly? Thank you.
 

How can you expect a reply from an 5 year old thread.

Instead open a new thread
 

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