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Old 05-03-2011, 01:39 PM   #341 (permalink)
DJBecker
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Quote:
Originally Posted by adamj12b View Post
Currently the revolt is basically a constant current power supply. The duty cycle is always changing to maintain a steady current output.
You forgot to add the caveat "with a suitably large inductor". I'm sure you know this, but not the casual reader.

Without output smoothing, the Cougar will have bad behavior with many batteries. LiFePO batteries, which look pretty much like capacitors in the time frames involved, will absorb huge current pulses in the first few microseconds putting the controller at risk. Most lead-acid batteries will heat rather efficiently charge.

The Cougar runs the PWM at about 8KHz or 16KHz, which requires a pretty big inductor. It could be much smaller with a frequency 4x-10x higher. And a smaller inductor might have lower resistive losses, which could offset the higher switching losses. Perhaps.

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