I am using a battery to power an Odrive micro, and I would like to use torque control with negative torque values in order to control the spin-down rate of a flywheel driving a motor. One additional thing to note - I need to recharge a battery during flywheel spin-down. So if I use negative torque control, will the controller use the motor as a generator by attempting to manage the amount of current generated and pushed back into the battery (desired), or will it instead use battery power to reverse-motor and slow down it’s rotation (not desired)? Thank you!
Hi! Whenever the motor is slowed down, it’ll regenerate power into battery. This isn’t just with a negative torque – it’s whenever the torque is opposite from the motor’s velocity sign. So you’ll regenerate power if the motor velocity is positive and torque is negative, or vice versa.
Got it! How is regeneration managed by the controller? Does power just passively flow through the reverse current resistors, or is a PWM switching scheme used which allows for flyback boost and full torque control even when the generator EMF is lower than the battery voltage?
Very similar to the second! In fact, the ODrive doesn’t even differentiate between consuming power and generating power – the inner loop operates all on torque setpoints, and it pulls or regens the power needed.
Great, sounds like it will behave the way I need it to! And I realized I made a typo in my last response - I didn’t mean to type “resistors,” I meant Diodes.
Thank you for the help.
No worries, figured 
Best of luck, please let me know if you have any other questions!
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