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Originally Posted by MPaulHolmes
That sounds good to me. The clarke and park transforms and their inverses are easy peasy.
What is more tedious is the space vector modulation part, tuning the Id and Iq PI loops, and the running guess at the rotor flux angle. It seems like everything needs to already be working in order for it to work at all. A motor that just sits there isn't very useful for finding mistakes.
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Id and Iq determination ... The industrial controllers (AC in, AC out, DC bus between) all have a 'wizard' thing that steps you through a 'tune'. You enter the current and the voltage that the motor is rated for, it's rated rpm and frequency. The controller then pushes various pulses through the connected motor and determines about a dozen different parameters that it then uses to set up it's loops. Perhaps these parameters would be useful to you?
We (day job) power up each of our spare controllers once every 2 years on a Preventive Maintenance (PM) schedule. During these PMs I was planning (I have not started as yet) on getting our electricians to connect up a motor. Likely a different motor for each size of controller. After hours, I will run through the wizard setup and grab the parameters. When I see these parameters, they sorta make sense to me .. although I don't understand a lot of what they are for.
I am aware that the parameters are slightly different for EACH motor, even if they have the same part numbers. But if I can match voltages and currents to AC motors being used by all of us, I may be able to come up with something that you can start with. It will still take some 'playing around' to get it perfect ... but I'm all about GOOD ENOUGH.
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I guess I need a strategy for finding bugs without the motor actually turning. Maybe a bunch of data that could be looked at.
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Motor turning or not. During one of the demo/training sessions I went to (salespeople dress up sales talks as 'training'), the controller had some optional magic loaded that would measure the back EMF closely enough to approximate a linear positioner ... you could turn the shaft by hand and get a readout from the controller regarding angle and number of revolutions. Perhaps the PIC libraries don't do that. Perhaps the libraries are there and it will be easier to find now that you know about it. My point is that it is possible, at least. Powered up with no torque sounds pretty interesting ..
Let me know if you'd like some help on some task that you think you can split out.