Andrew L Billings, 49Genesee, PA

2021032, Oct 21, 2021

Oct 7, 2019

17/272362

- Woods Hole MA, US
Andrew S. Billings - North Falmouth MA, US

H02P 5/68
H02K 7/10
H02K 1/30
H02K 5/132

An efficient, large dynamic range electric motor system and method of operating same, including a frame, at least a first rotor-stator pair, together having a first dynamic range, and a second rotor-stator pair, having a second dynamic range, with the first and second pairs mounted within the frame for rotation about a common central axis of an output shaft, mounted for rotation about the first axis and configured to transfer torque from the first and second pairs. A clutch is configured to isolate at least one of the first and second pairs away from the output shaft, thereby establishing an at least one isolated pair, and preventing torque transfer between the at least one isolated pair and the output shaft. A controller is connected to the first and second pairs and is configured to control power delivery to the first and second pairs.

2017011, Apr 27, 2017

Jun 24, 2015

15/120519

- Woos Hole MA, US
Andrew Billings - Falmouth MA, US

B63H 21/17
H02K 5/173
B63G 8/08
H02K 7/14
H02K 21/12
H02K 5/132
H02K 5/22

A submersible thruster, and methods of optimizing and using same, including selecting a motor with an efficiency of greater than 75 percent when operated at 250 rpm immersed in a pressure-resistant fluid, the motor having a drive shaft with a rotor and a stator matched to the rotor, the rotor and the stator being immersed in the pressure-resistant fluid and being separated by a gap less than or equal to 1 mm. The motor is disposed in a housing to isolate the motor components from a liquid environment. A rear portion of the drive shaft extends through a low-friction shaft seal beyond the housing to drive at least one propeller within the liquid environment. Movement of the drive shaft is constrained to a radial and axial play each of less than 0.75 mm. The method further includes operating the motor at less than 50 percent of peak power, wherein said thruster operates at greater than 30 percent end-to-end thrust efficiency within the liquid environment.