What kind of transmission is in our vehicles?

[7055]

Hi all, I was wondering if anyone could tell me what kind of transmission is in our vehicles that allows both the engine and the electric motor to both power the wheels. Also, do the electric motors have various gears?

 

[maby]

Most of the time, it's just driven by an electric motor coupled to each axle. I'm not sure if there is any gear ratio between the motor and the axle - not really need for one in principle.

At high speeds, there is a clutch that can directly couple the petrol engine to the front axle - this is what they refer to as "parallel hybrid mode". There is no gearbox in the conventional sense

 

[anko]

This kind: http://www.myoutlanderphev.com/forum/viewtopic.php?p=11152#p11152

 

[anko]

Fixed ration voor the e-motors. See http://www.myoutlanderphev.com/forum/viewtopic.php?p=13047#p13047. We do need a decent ratio to get decent torque at the wheels. And to get sufficient power as well. With a 1-1 ratio, we would only be able to get 60 kW e-power at the wheels from 100+ MPH.

Also fixed ratio for the engine (when connected): 1000 rpm is about 38 km/h.

 

[Kaboom]

I understood it to be some kind of CVT - is this not the case?

Thanks

 

[anko]

Definitely not the case :ugeek:

 

[Marksuk]

I understood it to be some kind of CVT - is this not the case?

I think partially but its a bit more complicated than just that as it has elecric drive too,

 

[jaapv]

There is no CVT transmission at all, just reduction gear boxes and a clutch to couple the ICE to the front wheels. Like Anko said. The relevant diagrams were published on the forum just now.

 

[Marksuk]

To quote the manufacturer, this is what they say it is.

http://www.gkn.com/media/News/Pages/GKN-Driveline-Multi-Mode-eTransmission-on-the-Mitsubishi-Outlander-PHEV.aspx

"The brand new GKN Multi-Mode eTransmission makes its debut on the Mitsubishi Outlander PHEV – the world’s first Twin
Motor 4WD Plug-in Hybrid Electric Vehicle with ability to charge on-the-go - being showcased at the Frankfurt Motor show this week.

Mitsubishi Motors’ new Twin Motor 4WD Plug-in Hybrid Electric crossover is powered by two 60kW electric motors, one in the front and the other one in the rear. They are fed by a large capacity lithium-ion battery. A petrol engine and a generator are also fitted.

The GKN Multi-Mode eTransmission used as front transaxle offers optimum performance in three different driving modes with two different power sources:


Pure EV mode, with the vehicle’s front axle and rear axle driven only by the electric motors, the front motor being attached to the GKN Multi-Mode eTransmission. Energy is sourced from the battery.
Series Hybrid mode, with the combustion engine driving a generator to charge the traction battery on-the-go whilst the car is still only driven by its front and rear electric motors;
Parallel Hybrid mode, with the combustion engine’s torque feeding through to the GKN Multi-Mode eTransmission to the front wheels via a hydraulic clutch which remains disengaged in both other modes. Front and rear motors then supplement the petrol engine. Battery charging still occurs too.

The GKN Multi-Mode eTransmission’s lightweight, compact design honed for high efficiency adds to the car’s extraordinary low CO2 tailpipe emission of 44g/km.

GKN Driveline’s global engineering director Rob Rickell said: “In their quest to find appealing packages for low carbon mobility, the vehicle manufacturers are exploring all possible avenues. With the new Outlander PHEV, Mitsubishi Motors has broken new ground and we are excited to have played a key role helping make this innovation a reality.”

 

[anko]

Let's add some more nuance to this. It all depends how literally we take "CVT".

Then engine produces RPM's which translate into generator RPM's. The generator produces AC with a frequency depending upon the generator RPM's but the AC is immediately transformed into DC by the generator control unit. The motors take the DC but the motor control unit immediately transform it into AC with a frequency matching the desired motor RPM's.

So, effectively there is a countinious variability between engine and axle RPM's (in serial mode, mind you) provided by the generator and motor control units. More or less how a torque converter in a conventional automatic gearbox provides continuous variability until it locks up. But the with way less inefficiency and way less risk of cooking it :mrgreen:

Some journalists (and owners as well) have mentioned a CVT. But Mitsubishi and several other journalists have mentioned a 'CVT like experience'. And many of us will recognize this. But personally, I wouldn't call it a CVT because, if we do, the next guy will ask questions like "does it have a push belt or a pull belt" or "how long before you need to replace the belt"

 

[user 258]

The simple answer is that at speeds below about 42mph it drives *like* a CVT because the engine speed is free to rev as needed since the engine is not directly connected to the wheels.
Kind regards,
Mark

 

[anko]

Way to simple Mark, as the same can be said for a torque converter and a ..... CVT :ugeek: