Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
How do you determine resonant frequency? Resonant converter can be hard switching series resonant LC converter or better soft switching LLC converter. Resonance frequency is mainly determined by the leakage inductance and series capacitance.
I think you are mixing several topics.
- An induction heater may use a parallel capacitor to compensate the low coil inductance (air coil or coil with large air gap)
- To convert the output switcher square wave to sine, you need a series inductor, implemented either as separate inductor or a by the transformer leakage inductance, and a series capacitor to put it in resonance. The function can be achieved by C1 || C4 in your schematic, C6 isn't needed.
- Finally, you want a certain amount of inductive load to allow zero voltage switching. Respectively, a parallel LC circuit would be tuned to a resonance above the switching frequency.
Make the total load impedance inductive to achieve zero voltage switching and reduce switching losses. General consideration about LLC operation modes apply.why does the parallel resonance frequency must be above the switching one?
Make the total load impedance inductive to achieve zero voltage switching and reduce switching losses. General consideration about LLC operation modes apply.
Variable frequency LLC isn't well suited for high power application. Phase shifted bridge may be the better alternative, achieving at least partly ZVS operation.
Variable frequency LLC isn't well suited for high power application. Phase shifted bridge may be the better alternative, achieving at least partly ZVS operation.
Because operation outside series resonance point is associated with higher switching losses.