4 ms·
If the car is not slowing down by clamping brake pads to a metal disc, then yes? I'm not sure how to answer the confusion here: confused on how regenerative bra
by mikestew 6y ago
If the car is not slowing down by clamping brake pads to a metal disc, then yes? I'm not sure how to answer the confusion here: confused on how regenerative braking works, or conventional braking?
- jimbokun 6y agoHow does regenerative breaking work?
- jeffbee 6y agoYou apply a load across the motor, the same way any electricity is generated.
- sliken 6y agoImagine a generator on a bicycle, you pedal to make a light bulb light up. There is of course inherent friction in the system, but a large fraction is actually pushing magnet fields around to produce electricity. That part actually has no friction, while it's not 100% efficient in the form of stray magnetic fields and some heating, normal metal on metal friction is a very small fraction. Normal brakes use 100% friction, which of course causes substantial heat, and increases wear and tear on the pads, the rotor, and brake fluid. These type issues are why it's often recommended to use a lower gear down hills so you can offload the brakes with engine friction. So not only does regenerative braking produce less dust, but it produces less heat, and the brakes/rotors/fluid are on average cooler and in a state where any needed braking causes less wear.
- beaner 6y agoI guess I wasn't sure how regeneration could occur through a process that is not frictive & therefore clean. And if there is a clean friction, why there wouldn't be one for disc breaks as well.
- Nasrudith 6y agoThe answer is that an electrical motor can also be a generator. An electrical motor when a current is applied causes it to rotate. When power is drawn from a rotating motor it generates a counter-torque proportional to the power extracted. Not perfectly efficient of course and there are still resistive and inductive losses but that means less energy dissipation by friction. This synergies beautifully with an electrical power system in boosting overall efficiency.
- beaner 6y agoSo in a way you could say that the friction resulting from engaging the generator has byproducts of both electricity and dust, rather than just dust produced by disc brakes? And that since the energy required to stop in both cases should be equivalent, it must mean less dust when using the generator, because the electricity subtracts from it?
- ip26 6y agoYou're headed in the right direction, the only thing you are missing is hybrids & EV's can generate 100% of their braking force with the generator during gentle driving. So no dust at all. They still have brake discs & pads, but mostly just for panic stops & holding in place when stopped.
- beaner 6y agoI guess I meant that even ignoring breaks entirely, there must be some wear ("dust") inside of a generator resulting from the rub of physical parts, but I take it to be a very tiny amount.
- deleted 6y ago[deleted]
- NotSammyHagar 6y agoThe generator has an axle that turns, sure, but it's much less than physical heating/ablative brakes.