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Old 08-25-2014, 03:23 PM   #1015 (permalink)
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That's great news, especially from the perspective of "getting the motor to spin."
One thing about these Toyota motors are that they are "buried permanent magnet" motors. This results in the motors behaving a bit like switched reluctance motors, especially at higher speeds. This allows them to overcome some of the back-emf and run at higher speeds. There's some great information about this in the Oak Ridge National Labs tests on the various Toyota hybrids. Here are two good examples:

Note that these tests also show some cool stuff about the boost converter and the inverter.

Regarding the resolver, I've decided that it would be best for this project if I run with the encoder position sensor. Analog Devices makes an IC that emulates an encoder with resolver input: AD2S1210

So, while I would like the "cleaner" input directly from the resolver, it will be possible to get this bad boy running with an adapter.

- E*clipse

Originally Posted by MPaulHolmes View Post
Software-wise, the differences are actually very minor. The main difference is computing the rotor flux angle. In the pmsm case, it's the rotor angle, so you just need to read the dang angle! In the acim case, you have to make a running guess at the rotor flux angle, using some formula that makes no sense to me. haha. In fact, it's the only formula from start to finish that I didn't derive myself. That bothers me, as it's hard to look for bugs when you are doing things that don't make sense. I haven't tried to make sense of it in several months, and I haven't tried that hard, so maybe I should give it another go. One interesting fact about the formula is, you cannot use it when the motor isn't turning, so FOC is useless at zero rpm. You need to use some sort of thing like V/HZ to get it turning, and then switch over to FOC. Otherwise, that formula divides by zero!!! NOO!!!

The PMSM motor also uses a resolver. If the motor is turning at 6000rpm, you'd have to check the angle at about 6.4KHz in order to get a resolution of 5 degrees (64 ticks per revolution). I think that's doable.
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