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MPaulHolmes · 09-24-2010, 01:51 AM

I still don't really understand it. haha. It sort of makes me happy though. I think once the controller is working, and I see lots of I_torque, I_field, and who knows what all graphed out, it will make a lot of sense.

I LOVE that new oscilloscope! Holy cow! I just put that sucker on each of the 6 pwm outputs, and it made debugging a million times easier!!!!!!!!!!!!!!!

I added a pretty strong (1kOhm) pulldown resistor to the power supply of the 6 HCPL-4506 optocouplers. Now, when I create an artificial overcurrent event, all 6 pwm outputs disable! Before, the power supply was left floating, sort of disconnected from the 5v supply by turning off a p-channel mosfet. The problem was, it was floating at around 2v, which was enough to turn on some of the optocouplers, since some have a better current transfer ratio than others.

So, I think the whole stinking thing works now! I really should check to see that the 6 undervoltage circuits are working. I have every reason to believe that they are.

I could NOT have done this without that oscilloscope. The motor WILL turn by Sunday... That's the rules. I didn't write them.

This is the first time I've ever made a circuit that only had 1 thing wrong with it. hahaha. 1 resistor out of like 290 components or so.

09-24-2010, 01:51 AM	#376 (permalink)
MPaulHolmes PaulH Join Date: Feb 2008 Location: Maricopa, AZ (sort of. Actually outside of town) Posts: 3,832 Michael's Electric Beetle - '71 Volkswagen Superbeetle 500000 Thanks: 1,362 Thanked 1,202 Times in 765 Posts	I still don't really understand it. haha. It sort of makes me happy though. I think once the controller is working, and I see lots of I_torque, I_field, and who knows what all graphed out, it will make a lot of sense. I LOVE that new oscilloscope! Holy cow! I just put that sucker on each of the 6 pwm outputs, and it made debugging a million times easier!!!!!!!!!!!!!!! I added a pretty strong (1kOhm) pulldown resistor to the power supply of the 6 HCPL-4506 optocouplers. Now, when I create an artificial overcurrent event, all 6 pwm outputs disable! Before, the power supply was left floating, sort of disconnected from the 5v supply by turning off a p-channel mosfet. The problem was, it was floating at around 2v, which was enough to turn on some of the optocouplers, since some have a better current transfer ratio than others. So, I think the whole stinking thing works now! I really should check to see that the 6 undervoltage circuits are working. I have every reason to believe that they are. I could NOT have done this without that oscilloscope. The motor WILL turn by Sunday... That's the rules. I didn't write them. This is the first time I've ever made a circuit that only had 1 thing wrong with it. hahaha. 1 resistor out of like 290 components or so. __________________ kits and boards