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Comment by isopede

2 days ago

Does regenerative braking work with a motor like this?

Yes: IIRC some large generators work exactly like this, as the energized rotor gives a lot more flexibility in managing frequency and power output.

  • Not just some, approximately all of them. It greatly complicates the logistics of a black start. † Of course that situation has additional complexity due to the need for substantial additional power in order for the various fuel supply systems to operate but I digress.

    https://en.wikipedia.org/wiki/Black_start

    • Generator excitation is not the hard part of a black start. You have to run coal feeders, blowers, and water pumps for an hour before you can spin the generator. Then you get power instantly upon applying power to the field windings.

      2 replies →

After watching a Munro video about it, I see your point. In the motor shown, the rotor gets its magnetic field simply by inducing a current and a field in it in reaction to the stator's field. There are no electromagnets in the rotor like I expected. In that case, I'm not sure either... I'd say more likely than not but it's complicated since the stator basically needs to induce a field and at the same time recover energy from the field that comes back from the rotor. I would further guess that the phase shift between the two components makes it possible to treat them separately.

Previous comment: Don't see why not - the "field" coils (the ones that replace the permanent magnets) need to be energized, which can initially come from the batteries if necessary.