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Old 05-16-2011, 03:29 PM   #1 (permalink)
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The Crimson Crawler - '04 Hyundai Elantra GLS
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Capacitor Bank for Open Revolt: What Size?

So I'm working on our controller using the new and improved controller PCB, the SMD current sensor, and the VLA based IGBT driver from mrbigh.

Here's what we got for IGBTs: 4x Fuji 300A 1200V

Running these IGBT's together would give 1200A. We plan on setting it to 1000A max current.

Based on what Paul said long ago in the main thread:

The ripple current rating is basically how much current can rush in and out of the cap without it overheating. The bad bad bad boys above can take a very large amount of ripple current each, so like 10 or 20 in parallel would have an extremely high ripple rating. (like 500 amps or something) You only need like around 5% of the max current for ripple rating, so they say. 50% is the worst case scenario.
5% of 1000 is 50A; I'd rather have a little more room for error, so let's say 8% (80A).

Is capacitance tertiary to getting a low ESR and high ripple current rating, or does it matter just as much?

Looking for best as well as least expensive route.

Thank you all!

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