Does the motor connect directly with driving axle? Or there is a clutch?
Does the motor stall when brake is pressed?
I understand there is no gearbox as torque is almost constant at any RPM.
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No clutch - speed of motor is linked directly to speed of the wheels.
Torque curve is generally flat from zero to a point where it starts to drop off until the motor is incapable of going any faster (around 12-15k rpm)
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So what happens to motor when brake is gradually pressed?
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EV Torque curve:
i.stack.imgur.com/e98Er.png
>>So what happens to motor when brake is gradually pressed?
Either it goes into freewheel (still spinning at a rate proportionate to the car's velocity) and mechanical braking slows the car, or more commonly the current runs in reverse turning kinetic energy back into electrical to regenerate the battery.
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>> So what happens to motor when brake is gradually pressed?
It would be off - no point spinning a motor when you're slowing down. Most EV's use brake regeneration to recharge the batteries - maybe some use the motor in reverse to achieve this?
Some cars like the Tesla will slow down significantly if regeneration is on by just lifting off. You do not need to use the brakes.
I think I am right in saying that Lyganos will be able to control deceleration in his MB B250e using the steering wheel paddles. So slow down only a little when you lift off to slowing down a lot.
In an EV you don't want to be actually braking too much - it's a waste of electric.
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>>
>> In an EV you don't want to be actually braking too much - it's a
>> waste of electric.
>>
Exactly the same as in a petrol car - as I've always argued, it's the brake pedal that wastes petrol, by throwing away kinetic energy heating the brakes that could have been conserved as energy in the fuel tank.
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>> Exactly the same as in a petrol car - as I've always argued, it's the
>> brake pedal that wastes petrol, by throwing away kinetic energy heating the brakes that could
>> have been conserved as energy in the fuel tank.
>>
Which would not be required if the pedal to the right of the brake pedal had not been overused creating speed which needs to be lost as you approach a hazard or reason to be going slower.
My kids all do this, as they approach a queue of traffic, instead of lifting off say 100 yards earlier they wait till much closer than I would before braking as they get closer to the queue, not because they have not seen it but because that was how they were taught to do it.
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>> My kids all do this, as they approach a queue of traffic, instead of lifting
>> off say 100 yards earlier they wait till much closer than I would before braking
>> as they get closer to the queue, not because they have not seen it but
>> because that was how they were taught to do it.
Mrs B does that - anoys me!
Since I've had a hybrid I think it has conditioned me to plan further ahead and max the regen. Its pretty easy in the Lexus as the Eco meter drops into the charge section as you brake - when it gets to the bottom (max regen) that's when you start using the friction material so over time you get to know how to get the best out of the regen
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How electric transmission works? - Lygonos
