Peugeot 205 Hybrid - Project

Hi everyone !
Like my title says, I will do a school project in my engineering school about the study and realisation of a Peugeot 205 Hybrid.
I am here to ask you, If you have any ideas about it.

Also, I plan to put an electric motor and I would like to know, where does it can fit in it ? (alternator, back wheels, differential ?)

With this car, with my team, we will run for the event "Europ'Raid" !

 

as always with car conversions you have a number of options, which you listed well.

replacing an alternator will mean that the electric motor will be more of an "assist", you cannot stop running the diesel engine, and you will need to develop some software, preferably with a torque sensor, which ensures that you don't fight the diesel engine (which has high compression).

replacing the engine entirely (into the exiating gearbox) that makes for electric, not hybrid.

at the differential, that involves modifying or even replacing the gearbox, which is a heck of an engineering job. if you have access to CNC equipment and the tools, go for it.

back wheels you have two options, both of which do not modify the front drivetrain at all but you need to write some firmware that monitors speed and throttle and preferably the torque on the front wheels (ABS sensors do the job) and ensures that you don't try to drive (or brake) the front wheels at a different acceleration from the back, otherwise it's dangerous

a. wheel hub motors. these are easy to fit but have the disadvantage of putting a hell of a lot of unsprung weight right where you least want it. hit a bump when the wheel weighs 50kg and things will not go well. i considered low-end QS203 motors but they are only really rated for around 500kg, a 205 is 800kg. any bigger than that though and even with alloy wheels it is risky, without active suspension (yes, someone has actually done that)

b. replacement axle, single drive motor. really for an 800kg vehicle you should put in a static (frame mounted) motor connected to a differential leading to a pair of splined axle shafts (same as at the front). use modern lightweight materials (save weight, or get size down) you can if needed cut a bit of the boot out to get some clearance for the motor and diff, reinforce it though (box it in). ideally you should create a bolt-on replacement for the whole rear suspension, or if you are really lucky might find some sort of kit online that can be adapted.

just as i said watch out for mismatched acceleration. with considerable care in software you should be able to get regen from the rear by powering the front, but if you overdo it especially in poor road conditions or round corners there is the risk of the rear wheels coming loose, effectively like jamming on the handbrake, so be extremely careful, don't for god's sake experiment on public roads

your most important thing in software is to be able to make the electric part "freewheel". if driving at say 60mph where the motor is only capable (on its own) of achieving 30mph, you want to ensure that the electric motor is not (once again) acting as a brake. or exceeds its rated mechanical RPM. you do not want an electric motor that spins apart when you are doing 60mph on diesel, because the gearing in the diff that the electric is connected to is too low. but, at the same time you don't want the gearing too high otherwise if driving on electric, acceleration will suck.

use this online program i wrote (i was the author of PI Technology's 1993 SpecManager software) to get some idea of acceleration, gearing, RPM, weight etc. under different slope conditions, and good luck.

http://lkcl.net/ev/vehicle_simulator/output/Simulator.html