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Why inductor gets hot?
Inductors are designed on the basis of Ampere turns. So with the increase of current beyond max rated current the inductor will become non linear and after certain current limit core will saturate causing heating due to core loss as well as conductor loss.
Can air core inductors saturate?
Air Core Inductors offer numerous advantages, including: Saturation Free — Inductors with ferromagnetic cores tend to become saturated as current increases. Air Core models, however, have no core to saturate, and therefore are independent of electrical currents.
Why does my inverter output filter get warm?
First of all, note that that family of inductors has their current rating set by a 30°C temperature rise, and that they also lose nearly half their inductance at that current. I think that for this application, you’re going to want much beefier inductors to start with.
What should the output inductor switching frequency be?
The output inductor design depends on a few things and for me I’d want to establish what the PWM switching frequency is so for now I’m going to assume it is 50 kHz – this frequency has to be much higher than the 50 Hz waveform you are trying to reconstruct because the inductor output filter has to do two jobs: –
Which is the best inverter filter capacitor to use?
I thought metallised polypropylene capacitors were a good choice for an inverter filter capacitor and I have used them in the past with relatively low DC bus voltages (circa 24VDC) A 400VDC bus isn’t something I have much experience with my plan was to use a 680uH inductor like a Bourns 2322-RC and a 10uF capacitor like a Kemet R463W510050M1K.
When to use larger or smaller inductor values?
Both are in opposition – you want larger inductance values to get rid of the PWM but you want smaller inductor values to leave the power AC waveform free to flow through it. The filter low-pass cut-off frequency needs to be as far away from 50 Hz as it is from 50 kHz and this can be determined by: – Next, is deciding on the L and C filter values.