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Old 12-07-2016, 09:55 AM   #2909 (permalink)
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Originally Posted by MPaulHolmes View Post
Yes that's right. There's DC voltage monitoring now, but the only use of it at the moment would be to verify precharge. But I'm not even doing that right this second.
Hmmm ... the existing pre-charge (when powered with AC) uses the brute-force method. The full wave bridge has a resistor in series, connected to the positive bus. When the DC bus voltage charges through that resistor and gets high enough for the DC/DC converter circuit to work properly, the micro powers up, and turns on the main contactor. That contactor bypasses the pre-charge resistor.

Since I'm not using that (old and inefficient) DC/DC converter, and since I will be using mostly whatever voltage pack I have available for testing ... maybe I can implement the DC voltage monitoring for pre-charge?

I have NOT added the V/Hz to this code yet. It's a good idea though. It's pretty easy to get working. IT was version 0.001 a few years ago. I just need a lookup table, and to race through the table at a given frequency, with all 3 phases 120deg apart from each other.
Would it be a different call to a different library to put the PWM out to the IGBTs?

The method to switch to V/Hz from Field Oriented Control would take a bit of fool-proofing (we fools are very creative!) since I think your throttle is a torque command for FOC and it would be a frequency output in V/Hz?

I haven't seen code for the new board as yet. Is it time for a backup email or are you doing version control through git?
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