PMAC Tuning pro2 and other method of tuning the PI Loop

Hi All

I have a couple of questions about the PMAC Tuning Pro2 and in general on how to better tune the PI loop of the motor

First, my setup is a UMAC that controls a GeoMacro GMH152. The Motor to tune is a torquer motor.

1) is there away to tune the PI loop, other than the step response? I would like to inject white noise to the motor, if possible.

2) about the PI current loop tuning: I don't think the time scale of what the PMAC Tuning records is correct. My servo loop runs at 2250Hz, and if I look at the data gathering setup variable (i5049) during the test, it tells me that the clock divider is 1, so the data gathered from the PMACTunign should be 2250Hz, not the 9kHz supposed by the PMACTuning. This is consistent to what I saw on the performances of my actuator, but not on what the PMACTuning tells about the rise time and the badwidth of the motor. Am I missing something?

Thanks

gigi

In our tuning software we only have the step response. Of course this is just a PLC that executes on the PMAC and does data gathering. So you can build any other method you like and manually gather data. Just a matter of work and not having the interface to easily change gains. We usually use PLC30 and 31 for tuning purposes so you can upload these while tuning is open and has already done some moves to see what we have.

The Current loop runs in the phase task which by default is 9kHz. So to do any tuning and plotting we need to also gather at the phase rate. Since Pmac only gathers at the servo rate we must remember the present servo rate, change the rate to equal the phase rate, do the move and gather, change everything back. This is why the rate really is 9kHz as the program assumed for current loop tuning.

The acuator servo loop is closed at the servo rate. This is why you see its closed loop performance match the servo rate.