[DDDvvv]

hi
there's been no big progress on this project. the other day, i pushed the drive to output 30 amps continuous. no heat, no temperature rise at all. was running good, until the 30amp breaker on my mains distribution box tripped.


the caps are ok. i measured them before install, and they averaged 880 uf. no surprise there, since they are rated at 20%. i would get 4 of those 10000 uf caps on ebay if i were doing this again. (2 for $43)


i've been busy searching for a different donor car. wife says to get practical with my "stupid" electric car shennanigans. i cannot drive kids around in my planned conversion; a cargo van. "get a nice car, remember, we have three kids"


i think i found one. a 99 bmw 540i sport. the guy will take $1400. in pristine condition, but motor blew up. he took the motor out, to replace it, then ran out of money. so half my job is already done. he probably thinks im a sucker, i did not tell him of my plans (just incase he decides to not sell, and go electric). as far as he knows, im buying an engine and getting my buddy to install it.
here it is, in his garage. notice all the parts around, from the engine teardown.
bmw 540i.jpg

[Stiive]

Thanks for your reply. I look forward to hearing about any further progress.

That's a very nice donor car. I think here in Aus we have special rules with converting newer cars to make sure all the safety features (such as ESP) still work as intended. Maybe you should check into this in your area.

Apart from that, it'd be a very sexy conversion.

[DDDvvv]

theres no rules, no inspections over here. as long as its registered and insured, no one cares what you decide to drive, or what you are driving it with.

yes, very excited about this car. back in 2007, i wanted this same model, nearly grabbed one, and then my financial situation changed. got a 2000 jetta tdi diesel instead. the tdi just got totalled. so the big interest in ev.

the cost of maintaining the bmw brand of cars is ridiculous, and that was the greatest turnoff. and they feed on premium gasoline only!!!

i figured out that since the 4.4 liter motor is gone, life will be easier. it has been my dream car for the past decade, the car i would get if i won the lotto.

im picking it up this weekend, and the guy threw in a 2 ton hoist, and a low profile jack in the deal.

[subcooledheatpump]

As much as I like the Astro (well, love/hate), I think the BMW will make a more interesting conversion. Can't wait to see more

[JRoque]

Ah... the wife units. They all seem to be made from the same raw materials: arsenic and sandpaper.

That is a nice car but did you see the curb weight on that thing? At 3,800 lbs it's not the lightest and that makes a big difference in your conversion costs. No doubt it will be nice though and you must love your car first and foremost if you're going to spend so much time and money on it.

Ask about the transmission - any grinds when shifting? You'll probably end up needing a new clutch but ask how many miles that one has. How's the diff? Brakes? Were all recalls done? Any serious accidents?

There's a couple of guys here with Beemers that can give you pointers if you need them. Check the garage or evalbum.

JR

[DDDvvv]

transmission is automatic.

still in the car, hanging on cables. my plan with the astro van was to go direct (differential) drive. so the tranny has got to go.

the differential ratio is 1:2.81 . will switch to a 530i differential, which has 1:4.10 gear ratio, interchangeable, and costs around $150.(used)

im not worried about the weight at all. its like a big upgrade from the 5000+ pound astro.

was planning agm, but now im thinking lithium.

[DDDvvv]

last week, i thought of a easier idea about converting a vfd.

there's the usual approach of getting a large drive ( 75hp +), tapping into the dc bus, and you are good to go. this is easy, but this drives cost a fortune ( $ 2000 + for a used drive supporting vector control, encoder, and computer interface.

what if you could get a very cheap 100hp drive, and couple it to a small cheaper drive?

i set out to do just that.

2012-05-27 10.40.55.jpg

got this from ebay. reliance gp2000, 100 hp, 480v, working when removed from service, $150. had to pick it up 150 miles away, but it was worth it.

got it home and opened her up, and it was full of goodies.

2012-05-27 10.41.18.jpg

2012-05-27 10.41.34.jpg

400 amp 1200v igbt's complete with laminated insulated busbars, and a large square d 250 amp x 3 contactor.

this drive weighs 260lb, and is in a 5' x 2' x 3' cabinet. so whatever plans i have would involve getting all this goodies out of this cabinet, and designing a smaller lighter housing.

after gutting, this is what i got:

2012-05-29 11.30.23.jpg

from left:
power modules on large heatsink, with 300 amp fuse, and snubber boards
4 x 6800uf 450v caps
gate drive board
gate drive power supply
square d 250 amp switch
3 x 200 amp fuses.
size 1 assorted cables.

why gut it? this drive does not support vector drive, or any form of feedback. its old, and only does a blind v/f profile. (although it has current sensors on two of its outputs). so the control circuitry has got to be replaced by something more modern.

it has a powerful gate drive board, so im planning to tap into the gate drive. just the heatsink and power modules weigh over 100 lb, might have to be changed later, for weight saving. probably go watercooled.

interesting thing is, the power supply board takes 240v ac, although the drive is a 480v version. so im deciding between 230v or 460v conversion.
will probably go 460v since the current rating would have to double if i went with the lower 230v.

looking and studying this components, im beginning to see the design requirements of high hp ratings in this drives. from gate drive design to insulation, snubbing, and wiring.

going this way is also a good idea, since the cost would add up, if these components were purchased separately.

[aeroscott]

beauty! great source of parts.

[DDDvvv]

2012-06-02 13.00.42.jpg

2012-06-04 09.56.43.jpg

2012-06-03 14.15.54.jpg

finally got the donor. my father in law took care of the towing. thanks old guy.

all parked in my driveway which sadly will be my work zone. ofcouse, engine is missing. hopefully, thats a good headstart.

ill probably move to a new build thread.

the car weighs 4900 lb gw, but for $1400, i could not pass on this.

[Stiive]

Originally Posted by DDDvvv

from left:
power modules on large heatsink, with 300 amp fuse, and snubber boards
4 x 6800uf 450v caps
gate drive board
gate drive power supply
square d 250 amp switch
3 x 200 amp fuses.
size 1 assorted cables.

Nice one! What you thinking of doing for control? Could be a good KiwiAC candidate