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March 28 update on my AC controller testing
Quick Summary
I have some results ... but I have some problems as well.
Please look at Third and Fourth, as well as the attached log files.
Details
First - a trivial problem with my bluetooth headset. The bluetooth headset does not play nicely with the bluetooth on my gopro. So the gopro is not going to be recording video .. or I have to figure out how to shut off the bluetooth without being able to use the app ... inconvenient.
Second - a less trivial problem with my bluetooth headset. The AC controller interferes with the bluetooth headset when I get within about 2 feet of the controller ... I guess interference makes sense ... so I may have to use shielded VFD cable from the output of the controller to the motor terminals and pay some attention to grounding and shielding .. LATER!
Third - some control issues. In my previous setup, with a separate 24V battery pack .. and no DC controller .. I just turned on the DC motor and the rest of the testing was done on the AC controller.
Now, with both a DC controller and an AC controller on the same battery pack, the voltage on the DC controller is much higher. I would overspeed the DC motor if I put the throttle on too high.
With the AC throttle set to regen .. a lot of regen .. since I had not centered it after my last test ... the DC controller started to rotate the motor .. and the regen kicked in .. slowed down the motor .. and spun the motor backward before the AC controller could disengage. Only a couple of revolutions .. but quite aggressive. This may not be something that could happen in *REAL LIFE* .. but it IS INTERESTING!!
Fourth - So the method I tried was to dial up the AC motor until it started to rotate ... then back off the AC throttle to 0 throttle. That's where I started.
Start up the DC motor a bit (accelerate), use the AC motor to regen (decelerate). Back and forth ... up to about 200 amps. Accelerate with the DC controller, decelerate with the AC controller, rinse and repeat. Then the AC controller seems to just quit .. at least with regen. I fiddle with the AC throttle and it seems to recover .. and then it quits again.
The DC controller starts to spin up the motor out of control ... and I hit the slap switch to kill the whole thing. I don't know if the problem happens at a specific speed, or a timeout, or some other things that I have not thought of. But it is interesting.
I'm thinking that perhaps I should use a lower voltage pack so that the control issues don't spiral so quickly? It's something to try.
Comments?
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