Abstract: A motor generator set utilizing a compression or expansion turbine engine. Fixed to the shaft of this turbine engine are the drive and pick-up rotors of a brushless direct-current motor with permanent magnets, the turbine engine bearings serving also as bearings for the electric motor. Application to the momentary or continuous supercharging of reciprocating heat engines, to gas turbine power plants, to cryogenic units and to all plant installations utilizing a compression and/or expansion turbine.

Abstract: An electronic power supply device for driving a D.C. commutatorless motor utilizes a plurality of driving coils for supplying power to the motor and at least one control coil, magnetically interconnected with the driving coils, to generate a control signal in response to operation of the motor such that a power transistor, having an output connected to the driving coils, and an input controlled by the at least one control coil to provide the driving current to the driving coils. A Zener diode having a nominal breakdown voltage lower than the breakdown voltage of the power transistor is interconnected therewith.In modifications of the power supply device a flip-flop circuit, controlled by a control signal generated by the at least one control coil, controls the commutation of the motor by controlling the conduction of the power transistor.