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Unread 21-03-2011, 15:31
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Re: Partial Jag failure?

Quote:
Originally Posted by Al Skierkiewicz View Post
tech,
The VBuss is measuring input voltage so that the Jag can disable output when the input power goes down to dropout on the voltage regulators. The thought being that a significant load may be causing a large voltage drop in the input wiring. By disabling the output, the voltage can climb back up to full terminal voltage. There is no feedback in the controller from the output terminals.
I changed the color on your post so people could read it.
Thank you for the assistance with the text color.

They must use it for more than that...from readme.txt in the development kit...

Quote:
Additional advanced control methods are also available when using the CAN communication interface.

There are voltage compensation control mode, current control mode, speed control mode, and position control mode. Each of these modes is mutually exclusive and operate using a PID controller whose gains are fully programmable via the CAN interface. Each PID controller starts with all of its gains set to zero, so no output voltage will be generated by any of these modes until the PID controller is at least partially configured.

In voltage compensation control mode, the output duty cycle is adjusted to compensate for changes in the input voltage, resulting in a constant voltage output.
From controller.c:

Quote:
//
// Get the current bus voltage.
//
lVBus = ADCVBusGet();

//
// Compute the desired output PWM width in order to produce the desired
// output voltage, and limit it to the available range.
//
...
Though you are also absolutely right...neither model of Jaguar gets direct voltage feedback from it's output terminals.

Last edited by techhelpbb : 21-03-2011 at 17:17.
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