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Old 08-09-2016, 11:42 AM   #2819 (permalink)
thingstodo
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I don't have any code for V/F on this hardware. It was all FOC.

What do you think Paul? I like the idea of testing out the hardware with a simple Voltage proportional to Frequency.

To make it usable for motor control (if you lost your encoder and wanted to limp home?) you would need
- BOOST - offset initial voltage to get motor to turn at all - normally 0.5% -> 20%
- RATED FREQUENCY - for example 60 Hz, what to use as the end frequency, where max output voltage is reached.

The older controllers that use this have an option for the V versus F:
- linear : f/max : 1 Hz = 1/60th voltage, 30 Hz = 1/2 voltage. + BOOST
- pump : f^2/max^2: 1 Hz = K*1*1/60*60, 30 Hz = K*30*30/60*60 + BOOST
- fan: 1/f^3: 1 Hz = K*1*1*1/60*60*60, 30 Hz = K*30*30*30/60*60*60

For testing hardware, linear, no boost, should cover all of our needs?

I'm not sure that this would be easy to do with the present code. You'd need to set the frequency instead of the torque ... maybe bypass all of the math and use a different library to drive the IGBTs?
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