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EC doesn't have a core saturation condition, and I've been working on a power supply where I need a choke. I substituted a choke with a tranaformer's primary but got the notion it might saturate, because it lacks an air gap. Anyway, I made the experiment, it doesn't saturate even at 130% the required current, so I'm going ahead with it, but I wanted to try and simulate a sort of a saturated core condition. A saturated core is when the core has reached its maximum flux density, and cannot withstand any further magnetization. This is a process that occurs at low frequencies, and is mainly expressed by a loss of nominal inductance, a current spike, and no further increase in energy transfer. Although the process is not abrupt, and the core can still magnetise further, the more you try to magnetise it, the more current it will demand, and the less it will become magnetised (the process will slow abruptly). DC magnetization is a major problem for SE amps, where a constant amount of direct current is always imposed on the core. It's like, it's already working on a given level, and you try to increase it further. Without an air gap most transformers saturate quickly with DC. This is a nonlinear process, and that's why an SE output transformer is always larger than a PP transformer for the same power. The air gap reduces the inductance, and they make the tranformers bigger to reintroduce some of the inductance again. A rather meaningless process if you ask me. Anyway, the transformer I'll be using is designed for a 150mA primary current and 50Hz line frequency. The reason it doesn't saturate is because saturation is a balanced process between frequency and current. Since both are twice the nominal values, it's far from its saturation point.
Ok, now to the experiment. Flip the switch a few seconds after the simulation starts, and watch as the core becomes ,,saturated''. Yes it doesn't actually become saturated, but it's a close approximation. You will also notice, the core loses its regulating abilities, as the primary inductance collapses.
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