In this post, I’ll show you the induction heater I made. I bought the board and coil as it’s easier and quicker than making them on your own. It’s rated for 2000W but the maximum power I can get out of it is 1200W because that’s as much as the power supply I’m using can supply.
The driver can be powered with a voltage anywhere from 12 to 48 volts. I recommend going with the highest possible voltage to decrease the amount of current needed to achieve the same amount of power transfer. This means there will be fewer losses in the wires which in turn means you can use thinner power cables between the induction heater and PSU.
The circuit used to drive the coil is actually a ZVS driver. I already made a blog post where I made my own and used it to power a flyback transformer. The wiring for powering and induction heater would be just a bit different. Instead of attaching a flyback transformer to the output you attach the coil and connect the big inductor to the positive side of the output instead of the midpoint on the primary coil of the flyback.
I added a water cooling loop to cool the coil. In retrospect, this was probably unnecessary because when I was testing the water didn’t even get warm.
Note: Power supplies have a capacitor bank on the output which means that when you switch them on the voltage will slowly rise from 0V to the set output voltage. The problem is ZVS drivers have to be switched on very fast to prevent both transistors from turning on at the same time. This is why you first need to turn on the power supply and only then throw the switch into the ON position.