An electrical machine, such as an induction motor, comprises a stator having a plurality of conductive windings spaced around an axis of rotation, a rotor rotatable about the axis of rotation in response to the flow of current through the stator windings, and a plurality of switching assemblies provided at circumferentially spaced locations around the stator. Each switching assembly is electrically connected between an end of at least one of the windings and a power supply busbar ring assembly comprising at least one conductor. The busbar assembly connects the electrical supply to one or more of the switching assemblies, each of the switching assemblies being effective to selectively control the supply of current to at least one of the windings.
In one aspect, an alternator is described which includes a current control apparatus including a stator winding and a control winding, wherein current control in the control winding regulates the stator winding. In another aspect, a gas turbine engine includes a multiple-channel alternator for redundantly driving accessory systems. In another aspect, an alternator cooling scheme is provided, which alternator includes means for reducing stray inductance of stator winding end turns.
The invention includes an electric machine having a rotor, stator and at least one winding in the stator adapted to conduct a current, and a secondary winding, electrically isolated from the first winding and inductively coupled to the first winding, which may be used to control at least one of the output voltage and current of the first winding.