I have a 1 kW three-phase BLDC motor from China, and I was developing the controller myself. At 48 Vdc, the maximum current should be about 25 Amps and a peak current of 50 Amps for short durations.
However when I researched BLDC motor controllers, I came across 24-device MOSFET controllers which have four IRFB3607 MOSFETs per phase (4 x 6 = 24).
The IRFB3607 has an Id of 82 Amps at 25 °C and 56 Amps at 100 C. I can't figure out why controllers will be designed with four times the rated current. Keep in mind that these are cheap Chinese controllers.
You can see the controllers here, if you need any part of the video translated, please let me know.
Considering heat dissipation, these devices would be operating at 15kHz so about half of the loss would be switching loss.
Keep in mind that these are $25 chinese controllers and each mosfet would cost then about $0.25. I don't think these people care a lot about efficiency or quality. These controllers are warrantied for 6 months to 1 yr max.
BTW in the lay language of the users, Mosfets are called MOS-Tubes. Hence tubes.