[Propellator]

Quite a while ago I became interested in electric cars and - as most people here I guess - I thought I should convert my car. Living in Germany I couldn't really find a lively forum as this and since most of the diy components are from the US anyway I think its a good idea to keep in touch.

My car is a Saab 9000 which is a rather heavy beast at 3900lbs, but it offers plenty of space for the batteries without compromising transport capabilities.

I've been ploughing through Bob Brants "Building your own EV" and other interesting literature, am still undecided on AC or DC motors and hope to use LiFePos.

Philip

[Woodsmith]

Welcome to the forum.

The Saab is a big car but I'm sure there have been heavier ones converted.

What sort of range and performance are you looking at and do you have a budget for the build?
AC drive will cost more as there are not the range of parts and kits on the market. DC will be more conventional and easier as well as cheaper but it all depends on what you can do for yourself too.

If you have a good background in working with electronics then maybe you can build your own ac controller for instance.

have a browse in the 'garage' and see if there is a set up that may give you more clues as to how yours will go.

[bliksem]

Seeing that you live in Germany I will try and find a contact at Siemens.
They made the best ev inverters ,Simotion and Simovert. They also made
very compact watercooled AC motors. They do not sell to the DIY market and
now are focusing only on larger drives for commercial vehicles. There must be some floating around in labs and "graveyards".

The key would be to make the right contacts.
Good luck and keep us posted.

[Propellator]

I started with preparing a couple of excel sheets to find out what kind of performance will be available depending on components used.

I only have a rather short commute, but the car must be highway capable, so a top speed of 80mph is desirable. The range should be 50mls to 60mls at a 35mph to 40mph average speed.

Calculation presented a conversion cost of about 10kUSD to 15kUSD
using a DC system with a 20kWh LiFePo pack.

Although I'm an engineer by trade, my electrical engineering knowledge concerning motors is negligible. Which is one reason for me to be here.
Many people built succesful cars, even heavy ones, with a DC system, so there must be a secret to it I haven't grasped yet.

A Siemens motor would be pretty but sadly I don't have useful contacts in that direction.

Designing and building an AC controller would present a nice challenge and I'm trying to talk my electrical engineering friends and collegues into trying it. But they have their families and hobbies and so this would probbably also take ages to finish.

In the end I should just do it, order a WarP9, a Zilla and some LiFePos and just see what kind of car the Saab becomes. At this point my calculation shows that, at 160V, I would be able to climb a 10% incline at 30mph.
Not good. Then again, it'll be good enough for my commute and where I live there are no hills.

[electromet]

Philip,

That's one heavy Saab at 3900 pounds. I know that it's reasonably aerodynamic, so the first order of business is to find the boat anchor that's being stored in there and get rid of it. Lighter weight will help your acceleration and aerodynamic improvements will extend your range at highway speeds.

And by the way, welcome to the forum.

Mike