Thread: Current Control
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Unread 20-06-2010, 17:08
EricVanWyk EricVanWyk is offline
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Re: Current Control

Quote:
Originally Posted by kamocat View Post

But check this out:
If I have my setpoint at 40A, and my proportional coefficient coefficient at 1, then it outputs 3.5 volts. (It also says my motor is drawing 2.25A at this low speed) Apparently, 1*(40-2.25) = 3.5 (Or rather, 3.5÷12 full power)
Does that mean that somewhere in here something's scaled incorrectly?
Marshall -

Something in my head just jostled loose regarding this statement.

The PID loop uses the current sensor as an input and gives duty cycle as an output. Therefore, the style of analysis you were attempting does not work in this situation. Your example becomes:

% on time = scaling_factor * 1 * (40-2.5)

instead of

Amps = 1 * (40A-2.5A)
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