[Farmadupe]

Out of interest, what could make such a design better than a traditional inductive motor? Such motors already suffer inductive losses, and do not need slip rings or brushes, and presumably do not an additional set of windings to transfer power to excite the stator?

Just could the two sets of coils be optimized for their own purposes?

[formerly_proven]

Inductive coupling in an ASM is at the drive frequency (hundreds of Hz), inductive coupling in an inductive electrically excited SM can work at an arbitrary frequency, e.g. 100 kHz. You can also see in the ZF release how small the coils for transferring the excitation current are compared to the main windings, they are the small rings on the left side.

[FirmwareBurner]

>what could make such a design better than a traditional inductive motor

Traditional induction motors, compared to these with wound rotors, are heavier and bigger in size for the same power output, and have less efficiency especially at starting/low-speeds.

[sidewndr46]

that is only true if you don't have a VFD. At that point you can basically get whatever you want out of them until they melt or blow out a bearing

[Loughla]

So then it comes down to cost? If this is cheaper than a motor and vfd, then it's still a win?

Source: the one time I restored a massive JT Towsley jointer and had to get a vfd for the giant motor I had to put on it. In other words, I have no idea what I'm really talking about.

[sidewndr46]

as others commented, this is not new tech. It's the result of the PR department needing to make a press release.