Hi all friends,

I am currently making a project of Induction Heater using IGBT, and for that I want to know:

How to find out the resonant frequency of the Induction Work Coil?

Any measuring device? any Formula or suggestions please.

Thank you.

 

If you have the inductance of the coil, the impedance is calculated by: Xl = 2∏fl, where f is the frequency and l the inductance.

You have to have another reactive, a capacitor, to get resonance. The circuit is resonant when Xc = Xl. Xc = 1/2∏fl.

 

Yeah....what He said.

I'm not sure the configuration your circuit will be...some induction heaters have a separate resonator coil (much higher inductance) across which a small portion the work coil is TAPPED. This was standard practice with the old Triode heaters, of course things might be different these days.

If the circuit uses a tapped work coil, the capacitance thereof is usually negligible...in fact the work coil is not resonant at all.

eric