Twin 10kW motors hybrid conversion

[centracing]

My name is Andrew and I'm from Vancouver BC. I'm planning a hybrid conversion for my 85 vw jetta with two 10kw motors driving the rear wheels with a custom suspension and the engine driving the front wheels as usual. I'm not sure how to get confirmed status but I hope this is enough because I've got a lot of questions lol.

[Morgen 3Eman]

Hi Andrew,

Your posts sounds like you are in for a lot of "fun", for lack of a better term.  Are you planning on direct driving the rear wheels, or some kind of power transmission path?

TTFN,
Dennis

[Bikemad]

I'm guessing a toothed belt and/or chain drive will be utilised along with suitable pulleys/sprockets to provide adequate gear reduction for increased torque that will be required for hill climbing and improved acceleration.
The gear reduction must not be too great, or it would cause the electric motors to be over-revved while being driving at high speed under ICE power.
A greater gear reduction could be used if the drive-train was fitted with a unidirectional clutch, which unfortunately would also prevent the electric motors from driving the vehicle in reverse. 

The motors (or more likely, intermediate jack-shafts) will be centred on the suspension arm pivot line in order to reduce the unsprung weight acting directly upon the rear suspension trailing arms.

Alan
 

[centracing]

Hi Andrew,

Your posts sounds like you are in for a lot of "fun", for lack of a better term.

TTFN,
Dennis

Ya fun is a good way to describe it lol.

I'm going to post my questions first so I'm more likely to get more people to read them, a more detailed description of my setup is below.

Does anyone have a power graph showing torque and power at RPM for the 10kw motors? the 5kw curve would be nice too, maybe I won't need such big motors!

Im curious to know what kind of range other people have gotten with similar motors, and how many battery packs/ what voltage your running.

Also talking about the controllers, what kind of information is sent out of the dynamic monitoring connector? and is it a serial type connection or is it a digital signal that can easily be read by a micro controller? I'd like to be getting an input for motor speed to my control unit.

Anyways here's my detailed plan,

I want to have it be able to run on electricity up to around 60 or 70 km/h (40-45mph) which is as fast as I go on my way to and from work, and hopefully have a range of at least 15kms which is the distance to work, and I can recharge there.


Alan,

As for mounting, I've narrowed it down to two options for the power transmission so far.

Option 1: mount the motors to the trailing arms and having a gear reduction with gears of an old transmission with shift fork and synchro attached, and have a solenoid driving the shift fork so I can disengage the motors at higher speed. The motor speed will hopefully be able to be synchronized with the wheel speed (via a separate micro controller and wheel speed sensor) well enough for it to slip in like you would when you shift your car without using the clutch.

Option 2 is to mount the rigid mount the motors and have a chain drive with a one way clutch or some other type of clutch. Although I will be needing to drive the car in reverse as my driveway is on a down slope! There would be ways around that but I would rather have some way of controlling when its engaged which is why option 1 is appealing even though I would be sacrificing handling with the unsprung weight and possibly the life of the motors with the increased shock associated with it being unsprung weight. However I saw that the was a kit available that had a motor mounted directly to a live rear axle which would experience about the same amount of shock as this setup I'm planning would. Also I believe having a chain drive would be less efficient.

I'm going to have another look at the rear suspension area tomorrow with it up in the air and see if I can make up my mind about mounting.

Thanks for your help guys.

[Morgen 3Eman]

Hmmm, I wonder how many HP an automotive air conditioner clutch can handle? 

TTFN,
Dennis

[Bikemad]

Does anyone have a power graph showing torque and power at RPM for the 10kw motors? the 5kw curve would be nice too, maybe I won't need such big motors!

The data and power curves are on the GM Website. Click on the button and scroll down until you find the Motor Performance Testing Reports links.

Alan