Joepage2008x2
Member
Hi everyone, a long time ago i started building an induction heater and kept having problems with my mosfets, i sorted that problem but gave up with the induction heater as i didnt have an oscilloscope. I started it again a few days ago after i got an oscilloscope and got it to work but my mosfets rated at about 55A kept blowing and can only manage 3A, i now only have a 10A IRF740 left. When i use my inverter circuit to power a bulb the mosfets dont heat up and have no problem but when i use it to power my tank circuit they get really hot and blow, i think its because its an inductive load and my diode isnt fast enough. What does everyone else think ?
If it is because of this, whats a good protection diode, i will be running it off 320V at between 1-5KW (when i scale it up, i dont want to buy 2 lots of diodes), 40-60KHz
![very basic induction heater.jpg very basic induction heater.jpg](https://www.electro-tech-online.com/data/attachments/31/31000-7e901b4e8ea26584944116e49f90e603.jpg)
Ignore the red numbers-it was done on multisim. Also i have a huge 250W 6Ω variable resistor in series with the power supply to adjust the current flowing.
This is a simplified version but is basically the same, also ive been using a 555 as the square wave input but i cannot get a 50% duty cycle, does anyone know a good VCO with 50% duty cycle, that can manage between 40-60KHz.
Thanks
If it is because of this, whats a good protection diode, i will be running it off 320V at between 1-5KW (when i scale it up, i dont want to buy 2 lots of diodes), 40-60KHz
![very basic induction heater.jpg very basic induction heater.jpg](https://www.electro-tech-online.com/data/attachments/31/31000-7e901b4e8ea26584944116e49f90e603.jpg)
Ignore the red numbers-it was done on multisim. Also i have a huge 250W 6Ω variable resistor in series with the power supply to adjust the current flowing.
This is a simplified version but is basically the same, also ive been using a 555 as the square wave input but i cannot get a 50% duty cycle, does anyone know a good VCO with 50% duty cycle, that can manage between 40-60KHz.
Thanks
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