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cajunfj40 · 03-17-2016, 10:45 AM

Hello again freebeard and thingstodo,

freebeard, I currently don't have an FJ40 - haven't for over a decade. See, I had one as my first and second vehicles (rolled the first one, put over 100K miles on the second) and then mostly parked it after graduating from University and needing to work. Eventually I moved, and took it with me, and by then it needed more than just some repair. So I took it apart to "restore" it but had no money, so it got piled up in the back yard and sat for ~7 years, and then I sold it and started a family and all that. I want back in, but I DO NOT WANT the ~12mpg mine had or the ~20mpg a diesel would get. A diesel conversion done right would likely be close to the cost of an AC EV conversion, if I can use junkyard OEM EV parts. Plus I want to be different. :-) Scouts are cool, too, but also suffer from Demon Rust - and I imprinted on FJ-40's, so they're not really what I want. if one has the cash, fiberglass body parts are available for both, and Aluminum for the 'Cruiser.

As for how the AC motor feels through a transaxle, that is good to know. Do you have an HPEV's AC setup? When you mention the torque hitting the knee and the motor choking, I recall from the peak power graphs for their motors that HP does actually peak on those, with the downslope almost as steep as the upslope, whereas on the OEM EV motors I'm thinking of (Leaf, Volt, etc.) they do a flat constant power region after the flat constant torque region. Should help some. There'll be a point at which it makes sense to shift up after the torque falls off too much, but it'll be a wider spread. I want liquid-cooled AC so I can sit there "stalled" on a rock without burning it up, and if it can keep liquid in I can seal it well enough for a dunking. Air-cooled brushed DC would be relatively easy/cheap, but keeping water out is much more of a challenge.

thingstodo, thanks for the insights! For aligning the two motors, I considered the rotors aligned by way of their built-in keys good enough, with the rest of the work being in aligning the two stators. As for possibility, AMR appears to sell "dual core" motors with single inverters, and IIRC those are IPM type REMY motor cores. No idea of the math needed, though! Sounds like trying to run two IPM or SPM or similar motors off the same drive may not be worth the hassle.

How much less critical is it to get two stator windings for induction machines equal in terms of resistance/inductance when running them in parallel off the same drive?

You said it is possible to run two OEM AC motor/drive combos in master/slave mode on a common (or geared/belted together) shaft. Any ideas as to how to control those drives? Mostly thinking OEM EV drives here - for common junkyard availability. For the aftermarket Curtis controllers, and many common industrial VFD's, they have that feature built in - just connect them up and put in the right settings. Not sure that is the case for OEM EV drives - and it seems like it would be an extra-cost thing that wouldn't be worth it to the OEMs to implement.

Hmm. I guess I could send the throttle signal to a separate "controller controller" and have it divvy up the torque demand to the two OEM drives, possibly with a current sensor on a phase of each motor to have a feedback for how well balanced the setup is running, if needed. Or just twin the throttle output and send it to both controllers at the same time, maybe monitor the current on/temperature of each motor for a while in early days to check the balance and see if it needs adjusting.

I've got lots of time to plan this out as the budget builds all too slowly. I'll probably end up buying a used Leaf to replace my currently dissolving ICE car as a commuter (different budget - I need to commute, after all!) for my first EV, as my toy budget may get big enough to buy a running/driving FJ-40 before it gets big enough to buy enough good parts to build one plus the EV bits.

Thanks!

03-17-2016, 10:45 AM	#6 (permalink)
cajunfj40 Lurking Eco-wall-o-texter Join Date: Dec 2015 Location: MPLS, MN area Posts: 128 Thanks: 0 Thanked 65 Times in 45 Posts	Hello again freebeard and thingstodo, freebeard, I currently don't have an FJ40 - haven't for over a decade. See, I had one as my first and second vehicles (rolled the first one, put over 100K miles on the second) and then mostly parked it after graduating from University and needing to work. Eventually I moved, and took it with me, and by then it needed more than just some repair. So I took it apart to "restore" it but had no money, so it got piled up in the back yard and sat for ~7 years, and then I sold it and started a family and all that. I want back in, but I DO NOT WANT the ~12mpg mine had or the ~20mpg a diesel would get. A diesel conversion done right would likely be close to the cost of an AC EV conversion, if I can use junkyard OEM EV parts. Plus I want to be different. :-) Scouts are cool, too, but also suffer from Demon Rust - and I imprinted on FJ-40's, so they're not really what I want. if one has the cash, fiberglass body parts are available for both, and Aluminum for the 'Cruiser. As for how the AC motor feels through a transaxle, that is good to know. Do you have an HPEV's AC setup? When you mention the torque hitting the knee and the motor choking, I recall from the peak power graphs for their motors that HP does actually peak on those, with the downslope almost as steep as the upslope, whereas on the OEM EV motors I'm thinking of (Leaf, Volt, etc.) they do a flat constant power region after the flat constant torque region. Should help some. There'll be a point at which it makes sense to shift up after the torque falls off too much, but it'll be a wider spread. I want liquid-cooled AC so I can sit there "stalled" on a rock without burning it up, and if it can keep liquid in I can seal it well enough for a dunking. Air-cooled brushed DC would be relatively easy/cheap, but keeping water out is much more of a challenge. thingstodo, thanks for the insights! For aligning the two motors, I considered the rotors aligned by way of their built-in keys good enough, with the rest of the work being in aligning the two stators. As for possibility, AMR appears to sell "dual core" motors with single inverters, and IIRC those are IPM type REMY motor cores. No idea of the math needed, though! Sounds like trying to run two IPM or SPM or similar motors off the same drive may not be worth the hassle. How much less critical is it to get two stator windings for induction machines equal in terms of resistance/inductance when running them in parallel off the same drive? You said it is possible to run two OEM AC motor/drive combos in master/slave mode on a common (or geared/belted together) shaft. Any ideas as to how to control those drives? Mostly thinking OEM EV drives here - for common junkyard availability. For the aftermarket Curtis controllers, and many common industrial VFD's, they have that feature built in - just connect them up and put in the right settings. Not sure that is the case for OEM EV drives - and it seems like it would be an extra-cost thing that wouldn't be worth it to the OEMs to implement. Hmm. I guess I could send the throttle signal to a separate "controller controller" and have it divvy up the torque demand to the two OEM drives, possibly with a current sensor on a phase of each motor to have a feedback for how well balanced the setup is running, if needed. Or just twin the throttle output and send it to both controllers at the same time, maybe monitor the current on/temperature of each motor for a while in early days to check the balance and see if it needs adjusting. I've got lots of time to plan this out as the budget builds all too slowly. I'll probably end up buying a used Leaf to replace my currently dissolving ICE car as a commuter (different budget - I need to commute, after all!) for my first EV, as my toy budget may get big enough to buy a running/driving FJ-40 before it gets big enough to buy enough good parts to build one plus the EV bits. Thanks!