[etischer]

Noob to the site, figure i'd introduce myself.

I just bought a 2001 Passat with the intention of converting to electric. I have also bought the Siemens / Ford 3 phase motor. Im planning on upgrading a 2 horse 3 phase drive to 90 horse by running external IGBT's. The vfd drive can run on 300vdc or 230v by tapping into the DC bus. Im planning on using a rubber rotoflex coupling to couple the motor to the passat manual transmission. The rotoflex couplings are used alot on driveshafts in BMW's Land Rovers and Jags. I plan on making the adapter plate myself.

I bought the car yesterday for $1800. It has a siezed cam due to oil starvation.





About 24 hours later Im almost ready to pull the engine out



I'll keep you all posted with my progress. Any one out there run external IGBT's on a 3 phase motor controller? That's my biggest unknown right now.

Cheers
eric.

[Weka]

eischer
What batteries do you intend to use, and how many with what weight and where do you intend to put them?

Great buy getting a Passat at that price -they are nice cars

[etischer]

I haven't done a whole lot of research on batteries, I was planning on buying optima blue tops just to get started. I need 24. Was going to put 12 under the hood. Maybe 6 in the trunk, 2 where the muffler was, 1 in the spare tire compartment, and 4 where the gas tank was. I think I could fit the remaining 12 in the trunk if I had to.

I am also looking at prius batteries, but I suspect I'd need atleast 5 packs. I don't like the idea of hooking up packs in parallel either.

I only need to go about 30 miles, and with 24 optimas, they don't need to be super huge ones. Peak current would be around 400 Amps.

The engine compartment has two frame rails that look pretty beefy. the trunk is quite large as well.

[etischer]

I decided im using ~5000 NiMH AA's for my battery. They have the highest energy density, and they are the cheapest per Watt*hr. They have a ton of surface area for cooling, and would be a light weight alternative to C, D, F cells. They are the most common battery, so I think the most research goes into maximizing their performance. I plan on building 50V 20Ah packs.

Each pack will be fan cooled, and have an array of 20 x 40 cells. 20 cells in parallel should keep the pack balanced, if a cell is dead, there will be 19 others to share the load. If a battery charges sooner, the current will increase to the ones that can still take a charge.

Here is a decision matrix I made.







I plan on using that rotoflex coupling to connect my motor to my transmission.







Cleaned out my engine compartment this weekend. Making good progress!

http://etischer.com/awdev/

[TheSGC]

Looking good! Just one thing, your pack size seems pretty small. 300volt x 22 Ah is only 6.6KW of power. And from looking at the discharge graphs, they would only give you 10 to 15 minutes of power at EV rates of discharge. I might be missing something, but from my own research, the only NiMH that would even be EV feasible are the F cells, and about the time those were all priced, the lithium was cheaper. Those 2/3 AA can deliver 10 amps for a little over 4 minutes.

That Ford motor originally powered the Ranger EV that used ~300 volts 90Ah NiMH cells. 27KW of juice.

[Craig]

Originally Posted by TheSGC

Looking good! Just one thing, your pack size seems pretty small. 300volt x 22 Ah is only 6.6KW of power. And from looking at the discharge graphs, they would only give you 10 to 15 minutes of power at EV rates of discharge. I might be missing something, but from my own research, the only NiMH that would even be EV feasible are the F cells, and about the time those were all priced, the lithium was cheaper. Those 2/3 AA can deliver 10 amps for a little over 4 minutes.

That Ford motor originally powered the Ranger EV that used ~300 volts 90Ah NiMH cells. 27KW of juice.

It's 6.6kWh if you're looking at the battery capacity.. btw that would be enough to drive 20-30km if it's anywhere near the calculations I had made for a similar car

[etischer]

This battery decision so far has been the toughest part of the project.

The reason for going with the AA size was discharge current. To get F cells in the 200A range I would need about 5000 cells, thats the same number of AA cells to get 200A. I don't need the capacity of 5000 F cells, Im only commuting to work, about 20 miles. I may add a few hundred AA cells to increase my safety margin. Half my commute is stop and go.

[etischer]

Got my motor. Here is how it sizes up next to my transmission.

[Denniscnc]

Good work!!

I was looking at your site and I think for best results on mounting the flange to the motor shaft is like you said get it machined but fit over the teeth, most likely the teeth are hardened so machining might be a pain especially with tooth interruption. Then once it's welded bolt the motor to a lathe if you have access to one and machine the flange face and back since the motor has a lot of torque that will be nothing for it and this way it will be perfectly perpendicular to the shaft.
And since it's a 3ph induction motor and if the shop has 3ph power that will solve the power supply problem.

Is there any feedback from the motor to the controller?
________
Honda XR350

[etischer]

I talked to three custom gear houses today, they say its nearly impossible to make a female part to slip over the helical gear. Looks like I will be welding or gluing.

I will probably try epoxy first. If I can get a machined part to slip over the motors gear, and extrude the epoxy up though the hollow shaft, that would be a ton of surface area.

Failing that I will have to weld.

I hope to be running the motor in sensorless vector. I don't know how successful I will be in tricking the 2hp drive into thinking its a 2 horse motor instead of 90 horse. I may have to run in Volts / Hz mode, in which case Im not sure I can do regen brake. I may not get sensorless vector working right away, I can also do encoder feedback with the drive. I might also be able to get the hall sensors working on the motor.

I could just run the 90 horse motor at 2 hp. I was thinking I could bolt up the motor and a bench grinder to a workbench and grind everything square.

I think this flange is the only thing I can't buy my way out of. Even drive line shops say they can't weld it because it won't fit in their machine. Looks like Im going to do this myself.

Originally Posted by Denniscnc

Good work!!

I was looking at your site and I think for best results on mounting the flange to the motor shaft is like you said get it machined but fit over the teeth, most likely the teeth are hardened so machining might be a pain especially with tooth interruption. Then once it's welded bolt the motor to a lathe if you have access to one and machine the flange face and back since the motor has a lot of torque that will be nothing for it and this way it will be perfectly perpendicular to the shaft.
And since it's a 3ph induction motor and if the shop has 3ph power that will solve the power supply problem.

Is there any feedback from the motor to the controller?