An electrical induction motor includes a plurality of windings, and a plurality of contactors. Each of the plurality of contactors is configured to be selectively opened or closed in a circuit including the plurality of windings to selectively connect the windings together in a star configuration wherein current flowing through the windings results in the generation of 2N magnetic poles, with N equal to the number of phases of the motor. Each of the plurality of contactors is also configured to be selectively opened or closed in the circuit including the plurality of windings to selectively connect the windings together in a mesh configuration wherein current flowing through the windings results in the generation of two magnetic poles.

Switch system for a motor vehicle electrical system comprising a first switch element arranged between a generator-battery line and a starter-battery line of a vehicle electrical system, such that the generator-battery line and the starter-batter line can be short circuited spatially in the region of the starter.

Method for starting an aeronautical free turbine and single-spool gas generator turbomachine of a twin-engine aircraft including two independent electrical networks each comprising a 28V battery selectively powering a starter-generator, in which, to ensure, under the control of a turbomachine regulation computer, the startup of the turbomachine first at a voltage of 28V by putting the two batteries in parallel and then at a voltage of 56V by putting them in series while avoiding too rapid acceleration of the gas generator, the serialization of the two batteries is ordered only once the combustion chamber of the gas generator is ignited and the speed of the gas generator is greater than a predetermined speed threshold N1 for ensuring, through this serialization, a positive acceleration margin at the point of maximum drag of the gas generator.