Abstract: An electric motor has at least one component that is submerged in a cooling fluid held in a fluid-filled cavity. The stator, rotor, and rotor shaft bearings are all possible components that may be submerged. The cooling fluid floods the stator, rotor, and/or bearings to cool the components. The fluid may have a high electrical resistance to isolate the motor components from any contact with flammable gasses as well as prevent arcs or sparks. The cavity holding the fluid also ensures continuous lubrication by preventing fluid from leaking or evaporating out of the motor.

Abstract: An electric start system (20) includes a controller (40) that controls operation of a motor (22) used to start a device such as a gas turbine engine (24). In one example, the controller (40) determines when an acceleration rate of the motor (22) is outside of a desired range and dynamically controls the acceleration rate. In another example, the controller (40) determines when the motor (22) is disengaged from the engine (24) and controls a torque reference value to facilitate smoother reengagement. In another example, the controller (40) provides an initial starting torque value that allows for soft starting capabilities of the motor (22).

Abstract: A method and system for monitoring the performance of a permanent magnet device, such as a motor or generator, and providing early detection of motor performance deterioration. The back electromotive force (EMF) of the motor is measured at selected conditions when the motor is in a normal healthy condition to obtain a reference signature response. A measured signature is then obtained periodically during the life of the motor at the same conditions as the reference signature to check the current back EMF characteristic of the motor. If the measured signature deviates from the reference signature by a predetermined threshold, it indicates that the motor performance has degraded to a condition requiring attention.

Abstract: A turbine engine inspection arrangement utilizes a motor that is otherwise utilized for starting the engine. An inspection interface allows for communicating with a motor controller to operate the motor in an inspection mode. During inspection, the motor moves the components of the engine very slowly or in an incremental fashion to facilitate visual inspection of the engine components, such as the turbine blades.

Abstract: A gas turbine engine system includes an electric starter motor which utilizes a partially hollow or cupped shaped rotor. Space is provided inside the rotor to fit the required clutch, bearings, and drive shaft. A rotor shaft drives the input shaft through the clutch. The clutch is mounted within a clutch cavity formed within an annular housing portion of the housing. The annular housing portion is at least partially conical and preferably extends at least partially within a hollow rotor mounted to the rotor shaft. A short package is provided due to the telescoped architecture while retaining the maximum length for electromagnetics.

Abstract: A gas turbine engine system includes an electric starter motor which utilizes a partially hollow or cupped shaped rotor. Space is provided inside the rotor to fit the required clutch, bearings, and drive shaft. A short package is provided due to the telescoped architecture while retaining the maximum length for electromagnetics.