Unable to monitor the speed (rpm) of motor eQEP module : TI C2000 F28069M

Started by bluenova333 2 years ago3 replieslatest reply 2 years ago210 views

Hello everyone. I am trying to run the closed-loop V/F scalar control of a 3-phase Induction Motor using TI C2000 TMS320F28069M Board. The first step was testing the open-loop and it works perfectly. Now I'm trying to take signals from the speed encoder attached to the motor and see in Code Composer Studio the speed of the motor in rpm. However, the 'rpm' expression is giving some incorrect random values. Can someone please check it also suggest if I'm missing something?

The file:

V_by_F control_Open_loop_trial_encoder.zip

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Reply by drmikeMarch 4, 2022

It's been a very long time since I worked with CCS.  I'm betting if you go line by line and explain what you are doing to someone else, you'll see your mistake pop out.  Sometimes it's a "1" where there should be an "i", sometimes it's a missing term, and sometimes is a pointer that is never actually initialized.  

The process of explaining is not the same as the process of checking.  It's amazing how we skip over things - like the ape costume in the basketball video.  Even if the person you talk to has no idea what you're talking about, you'll find the problem pretty quickly.

Good luck, and have fun!

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Reply by kschutzMarch 4, 2022
I agree with Dr. Mike. What he suggests is an amazing Jedi-mind trick that works surprisingly often! Talk yourself to the answer. The other thing you essentially always want to do is take baby steps, which you may already be doing, not trying to sound lecture-ish here. One such baby step could be taking whatever example(s) TI provided with their evaluation board and making sure said code/hardware combo all play nicely together producing the results TI got.
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Reply by philipoakleyMarch 4, 2022

In line with the other replies, try explaining the code to a video recording as if you'll be publishing the explanation of how to debug to YouTube (other platforms available;-). 

Having a bath duck handy can help, or play a nodding head video in the corner of your screen as if on a Zoom call. 

Whatever it takes to vocalise what your brain would otherwise skip over!