Another one arrived.
First thing I noticed was the tag saying it was from a 2015 model, and the larger plug on it. It reminded me that I read, somewhere along the way, that in 2013, they upped the power output. I eventually tracked down a snippit that said they were 8.5kw to begin with, but changed in 2013 (presumably for '14 model year?) to 10.5kw. Interesting.
For comparison:
Thicker wires too:
Nothing looks different inside:
Thought they just changed the connector, but they had to widen the casting a bit to make it fit:
Otherwise, they seem identical. Same thickness of windings and number of strands, voltage output spinning at the same speed is identical, pulley and coolant tubes are the same size and they weigh exactly the same(at least on a scale that only does 1/10 of a pound increments).
Hmm. Interesting. Guess they decided the internals were a bit higher rated than the externals? Or just decided it would be cheaper to push it to it's limit rather than redesign the whole thing.
The short bus-bars(the solid metal the wires are bolted to) on the "8.5kw" are a nice shiny silvery color:
(They're reflecting what's around them - the gold of the bolts to the right, the black of the insulator to the left.)
Whereas the "10.5kw" one, the bus-bars have that lovely dark rainbow effect caused by heat:
Maybe they changed their generation strategy for fuel efficiency, opting for more amps at less volts? Lower engine speed = more efficient for low power output, right? right. Your guess is as good as mine.
Part number changed, though it's close:
The junk yards seem to think they're the same. Maybe they send the plugs with them for a reason(though it's probably just because it's quicker to cut them out). With the plug, you could hook a later one up to an earlier model with no bother.
Digging around, trying to find anything solid on the kW rating, I found a snippet that explained the hybrid starter-generator (HSG) as being a "IPMSM" - an "Interior" Permanent Magnet
Synchronous Motor...well, that explains a lot(or at least gives rise to theories that make sense) . Like...the low level of cogging...why the brushless control found it easy to pick up the back EMF to determine timing...and presumably why there was such a large difference between the input voltage on the controller and the rectified voltage output. (Square wave vs sine wave)
As it's a PMSM, it can supposedly reach 95% efficiency. I suppose I could look at so-called sine-wave controllers...there's a 3kw, 72v one for under a hundred bucks on Ali...but if I ever want to see full potential out of these things, I need to look at Paul's 3-phase, vector controller...
That sounds like too much work.
