3 ms·

You should take into account that regen braking (even with resistors) only works at high rpm. The final phase of the braking you need to put even more energy in

You should take into account that regen braking (even with resistors) only works at high rpm. The final phase of the braking you need to put even more energy into the coils on top of what the they already must dissipate for braking the car. Electrically, you would need to run the engine in reverse to come to a full stop.

kwhitefoot 4y ago
> You should take into account that regen braking (even with resistors) only works at high rpm. It's note even with resistors it's only with resistive braking that this applies. If this is an electric car then the inverter can be programmed to give pretty much any braking force you desire just by altering the phase of the driving waveform. This can be done at any rotational speed. My Model S can dump 50 kW back into the battery so long as the battery is not fully charged. At 60 km/h the kinetic energy of the car is about 300kJ so the car can be brought to a stop in about six seconds purely by regenerative braking. In the final phase of braking the car has hardly any kinetic energy left so the huge 250 kW motors can easily bring the car to a halt and hold the car still just by balancing the magnetic forces in the motor against the motion of the car or gravity. In fact this is exactly what it does when running on traffic aware cruise control in stop go traffic, whether on level ground or on steep slopes.