regeneration basic theory

regeneration basic theory

Hi everyone,

I have a question that I hope someone might be able to clarify.
With respect to regeneration, I understand that it happens when the back-EMF of the motor is greater than the applied voltage to the motor (dependent on the speed of the motor). So let's say our vehicle is on level ground. We have a 24V battery but we're applying only 12V to a DC PM motor and we arrive at some steady state speed at 12V. If we then decelerate to 6V or brake, regeneration happens.
I've read in literature that its not necessary to have a boost converter and that regeneration happens inherently within the topology of the controller. So my confusion is this: How is it possible to engage regeneration when the battery (24V) voltage is much higher than applied motor voltage (from 12V to 6V)?

Thank you in advance for your insight and clarification.