What is the max. Pitch of the PHEV

[ganderpe]

I've got an PHEV MY16 and im very happy with it

Now we're leaving Switzerland and are moving to Teneriffa.
There are very steep Streets there with even more then 30%.

Now I was reading somewhrer in the internet, that the max. Pitch should be 30%.
But I don't trust this Statement:

The Facts are:

Electric Motors:

Front motor (S61) Max output
"kW (PS)" 60 (82)
Torque "Nm (kg-m)" 137 (14.0) 4182 U/min
Ratio front emotor: 1:9.663

Rear motor (Y61) Max output
"kW (PS)" 60 (82)
Torque "Nm (kg-m)" 195 (19.9) 2938 U/min
Ratio rear emotor: 1:7.065

Tire Diameter: 0.7m

In combination this makes a Driving Force:

F = ((137*9.663)+(195*7.065))/0.35 = 7718.5 N

The Force to overcome with 30% and Mass of 2000kg is:
20000*sin(atan(.30)) = 5746.9 N

or the other way, what % are able with 7718.5 N:

100*tan(asin(7718/20000)) = 41.8 %

I don't need 41% but a liitle Safety would be nice.

And I know, the ICE is probably needed (depending on the Speed) to produce Electrical Energie.

Does anybody Experience on this matter?

Peter

 

[ganderpe]

Found the answer in this forum:

https://youtu.be/WSho8T_Sxlg?t=42

 

[robdickinson]

I would say thats 'enough'!

 

[PeterK]

Hi ganderpe

I was in an offroad training last year with our MY16 PHEV. It done well with all the Jeeps and Lancruisers, but the ground clearence was setting the limits (and the winter tyres ).
I also tried to drive up a stair (which was part of the off road area) with a 100% pitch (45 degree).

Due to the clearence thing I drove carefully on the stair (all 4 wheels were on the stair) and stopped the car to check the situation. Then I wanted to drive up the stair slowly but just nothing happened after pressing the gas pedal. No electric power, no ICE engine power. No movement. Nothing (even no warning message). I was a really confused for a moment, moved the PHEV a little bit back until it was near the 30 degree angle and then tried again at low speed to climb up the stair which was successful (like the posted video from Japan).

At the end of the stair I scratched the housing of the battery pack underneath (clearance !) but my garage told me that there was no damage. Over all it was a nice experience.

My conlusion about this:
If it is too steep you can't move the car from stop, there must be some limitation in the max. current for the electric motors which is below you theoretical calculation for the max. pitch. But up to 30 degree will work !

PeterK

 

[greendwarf]

We've had this before and it's nothing to do with pitch. The electric motors won't climb over a small sharp ridge e.g. a brick, curb etc. from stationary - you need a run (momentum) to start it climbing. As I recall, it is the way electric motors deliver power to the wheels.

I have seen a Japanese video of the PHEV driving a ramp which appears to be more than 45 degrees at the top - starting from flat in a smooth curve.