Flux Vector Control 2

[marshg]

I have configured a flux vector control drive to run a belt conveyor that moves a 40lbs load using a 1hp motor. The motor is designed for this type of drive.


Here's the problem:
Our customer was running the conveyor at 300rpm and it was running fine for a while. Now it stops and then starts back up on its own. This tells me that that the motor is starting to overheat, which our customer had complained that the motor was getting hot.

1) I had him increase the speed up to about 600rpm (rated is 1750) and see if the problem went away, which would have told me there would of been a problem with the fan. It didn't go away. BTW, We are going down to the site on Wednesday to investigate further.

2) I called up tech support to ask them what the problem could be.
- They informed me that the motor may not have enough torque at that speed to run the conveyor at that speed. Btw, the belt was tight and our customer loosened it up w/out success.
- Tech support also said the motor may be overworked too.
- I asked him if I could have caused any of these problems by the parameters I programmed into the drive. He told me the only parameters to check were the rated voltage and current, which I did. I am unsure of this because my customer is in contact w/ another tech guy from the same company and he says that the problem is the way I tuned the drive.

What I really need to know for sure is if there is anyway that I could have messed up with one or many of the parameters that I configured (i.e. mag amps, current integral or proportion gain, stator resistance, etc.) that would be giving us this problem??

Thanks in advance. If anyone needs more of an explanation, let me know and I can send you a phone number to get in contact with me. Thanks!

 

[Marke]

marshg
I understand that you measured the torque on the shaft with the bigger pulley. This means that when coupled, the motor shaft will be running faster than the shaft you measured. The torque on the motor shaft will be less than on the measured shaft by the ratio of the two pullies. i.e. if the small pully is half the size of the larger, then the torque will be halved. speed times torque is constant.
If the torque is still too high, you can further reduce it by changing the pulley sizes, but this will reduce the maximim speed of the conveyor at the rated speed of the motor.
Best regards,

Mark Empson

http://www.lmphotonics.com