Abstract: This electric motor includes first permanent magnets secured integrally to an outer periphery side rotor and second permanent magnets secured integrally to an inner periphery side rotor. The first permanent magnets and the second permanent magnets are arranged so as to offset the relative torque produced between the outer periphery side rotor and the inner periphery side rotor based on the magnetic flux of the inner peripheral permanent magnets and the outer peripheral permanent magnets.

Abstract: A three-phase opposite rotating motor of a fan comprises a stator having a three-phase coil set without a core, a first rotor and a second rotor. The number of the poles of the first rotor is unequal to the number of the poles of the second rotor. The ratio of the number of solenoids of the three-phase coil set and the number of the first poles of the first rotor is 3:4, and the ratio of the number of solenoids of the three-phase coil set and the number of the second poles of the second rotor is 3:2, to ensure the motor works normally in an opposite rotating operation.

Abstract: Generator, motor, closed circuit surplus and overcoming the lost and gained power. Then the electrical dose comes out of the generator on the unifiers and then to the storing unit and then to the oscillator to prevent reconciliation between the generator and the engine, and vice versa and then attending to the engine and then the engine gives motion to the generator and the generator gives motion to the engine and it remains an exchangeable operation and then the katawet is put between the battery and unifiers to control the stream attending on the battery and engine.

Abstract: A small, lightweight relative drive device is provided, which is capable of producing large torque. The relative drive device of a two-phase magnetic excitation type according to an aspect of the invention comprises first and second coil groups and a magnet group. The magnet group includes magnets disposed with alternating north and south poles facing the first and second coil groups. The first and second coil groups are disposed at positions that are out of phase with each other by an odd multiple of ?/2 in electrical angles. The coils in the first and second coil groups have substantially no magnetic material cores, and the relative drive device has substantially no magnetic material yoke for forming a magnetic circuit.

Abstract: A power system includes an engine, a motor/generator operatively connected to the engine, and a starter operatively connected to at least one of the engine and the motor/generator.

Abstract: A control system for an electromagnetic rotary drive for bearingless motor-generators comprises a winding configuration comprising a plurality of individual pole pairs through which phase current flows, each phase current producing both a lateral force and a torque. A motor-generator comprises a stator, a rotor supported for movement relative to the stator, and a control system. The motor-generator comprises a winding configuration supported by the stator. The winding configuration comprises at least three pole pairs through which phase current flows resulting in three three-phase systems. Each phase system has a first rotor reference frame axis current that produces a levitating force with no average torque and a second rotor reference frame axis current that produces torque.

Abstract: A controller able to efficiently operate an electric motor of an axial air-gap type as an electric motor and an electricity generator is provided.

Abstract: A tandem rotary electric machine for vehicles is equipped with a primary rotary electric machine and a secondary rotary electric machine arranged in tandem mechanism, namely, of a dual stator-rotor pair mechanism. In the tandem rotary electric machine, a connection lead wire connects a stator coil wound on a stator core of the primary stator-rotor pair to a rectifier device through one of accommodation parts formed in slots of the stator core of the secondary stator-rotor pair. This structure reduces the entire size or volume of the tandem rotary electric machine and increases the mechanical safety against the impact or force from outside.

Abstract: A system is provided in a permanent magnet (PM) machine comprises a stator, a rotor configured to rotate relative to the stator, a first set of windings disposed within the stator; and a second set of windings wound back and forth toroidally around the circumference of the stator. In accordance with an embodiment of the present technique the set of windings is configured to generate a magnetic flux saturating the stator so as to limit fault currents within the PM machine.

Abstract: The invention is intended to obtain a rotating electric machine with a built-in control device in which the control device is kept from receiving heat from a main body of the rotating electric machine and the control device can be cooled in a desirable fashion. A heat sink (13) on which switching devices (12) of a control device (400) are mounted is attached to a rear bracket (6) by means of conductive studs (300) with a particular spacing provided in a left-to-right direction of FIG. 2. The heat sink (13) is cooled by a flow of cooling air induced by an unillustrated fan. Since the control device (400) is attached to the rear bracket (6) of which temperature increases with the spacing provided therefrom, it is possible to suppress heat transfer from the rear bracket (6) and effectively cool the control device (400) through the heat sink (13).

Abstract: A rotary power converter apparatus for coupling power between a prime driver and plural generators. The apparatus includes a frame having a first and second bearing aligned along an axis of rotation and a rotor assembly supported thereby. The rotor assembly includes a shaft fabricated from a light weight material that is rotatably supported along the axis of rotation by the first and second bearings. There is a prime-driver rotor assembly, that has a magnetic structure supported by a light weight non-magnetic alloy hub that is fixed to rotate with the shaft. There are also plural generator rotor assemblies, each having a permanent magnet structure supported by a light weight non magnetic alloy hub also fixed to rotate with the shaft. A prime driver stator assembly is fixedly supported by the frame and aligned concentric with the prime driver rotor assembly to enable magnetic coupling of power therewith.

Abstract: A magnet assembly includes a back iron and an array of magnets. The back iron is in the form of a plate having opposed surfaces. The magnets are arranged along one of the surfaces, with the other surface being dimensioned and configured according to the magnetic field distribution associated with the magnets. The back iron geometry provides for reduced mass, reduced leakage flux, and high flux densities to improve performance of a linear motor that employs such a magnet assembly. Additionally, the back iron can be a magnetically conductive annular ring, such as is employed in a rotary motor. Moreover, the magnets can be arranged in a manner that generates a Halbach array to increase force output in a desired direction while canceling stray magnetic fields in other directions. Similar reduced-mass designs can be employed in conjunction with a back iron of a fixed cross-section and magnets of variable thicknesses, variable lengths, and/or variable widths.

Abstract: A motor generator is provided with a stator having a winding around each of a plurality of stator teeth, and a rotor having a plurality of permanent magnets by the number larger than that of the stator teeth, arranged in the circumferential direction at equal intervals. The stator teeth are formed of a first stator teeth section including a plurality of stator teeth groups I, II, and III each including the adjacent stator teeth around which a winding to which the same phase voltage is applied is wound and in which winding directions of the stator teeth are opposite to each other, and a second stator teeth section including a stator teeth having a winding wound therearound and being placed among stator teeth groups of different phases such that electric power is independently input and output with respect to the first and second winding sections.

Abstract: The invention includes an electric alternator/motor having a rotor, stator and at least one winding in the stator adapted to conduct a current, the machine also having and first and second magnetic circuits, one of which includes a saturable portion in which saturation may be controlled to permit control of the machine.

Abstract: A motor and a generator both comprising a rotor and a stator, wherein said rotor and said stator of both said motor and said generator can rotate about a common axis, and wherein both said stators are coupled, and both said rotors are coupled, for one to induce rotation to the other, and wherein the rotation energy may be transferred to a system.

Abstract: A motor/generator includes a rotor member, a shorting member and a stator. The rotor member has a plurality of permanent magnets. The shorting member is configured and arranged to selectively establish a short-circuit in magnetic flux of the permanent magnets to switch between a normal state in which the magnetic flux is not shorted and a shorted state in which the magnetic flux is shorted. The stator has a plurality of coils configured and arranged to be energized with a composite electrical current including first and second current components. The stator is further configured and arranged to form a first magnetic circuit between the coils and the permanent magnets with the first current component to drive the rotor member and to form a second magnetic circuit between the coils and the shorting member with the second current component to selectively switch between the normal state and the shorted state.

Abstract: Electric energy from a battery is employed to shift the permanent magnetic field located in a generator. A spring housing is located distal from the generator. An outer magnet housing enclosing an inner rotating magnetic housing is positioned between the generator and the spring housing. A shaft is integral with and turns with the inner magnetic housing. An end of the shaft distal from the inner magnetic housing passes through the generator and is actuated by a sensor mounted over the shaft end.

Abstract: In a vehicular drive system for a hybrid vehicle, in which driving forces of an engine and a motor are transmitted through a power transmission mechanism to driven wheels, a common oil stored in a transmission case and a motor case is used for lubricating the power transmission mechanism and the motor. During travel by using an engine, when a synchromesh mechanism operated by a shift fork isolates the motor from the power transmission mechanism, an oil return hole blocking rod, provided in the shift fork, blocks an oil return hole providing communication between the motor case and the transmission case, thereby preventing oil in the motor case from flowing into the transmission case, to lower oil level in the transmission case. Thus, during travel of the hybrid vehicle, driving force loss due to motor drag resistance and oil stirring resistance is minimized.

Abstract: The present invention provides an electric drive, including a stator (4) and a rotor (3), for a paper processing machine, in particular a printing press having at least two rotary subassemblies (1, 2), the stator (4) and the rotor (3) being separated from one another by an air gap. This electric drive is distinguished in that the one subassembly (1) contains the rotor (3) and the other subassembly (2) the stator (4).

Abstract: A magnetic rotating motor generator of the present invention comprises a rotating portion which is made of a non-magnetic substance whose periphery is provided with a group of permanent magnets tilted at a predetermined angle in an embedded manner; a group of electromagnets that are disposed adjacently to the rotating portion so as to oppose the group of permanent magnets; a positional sensor for detecting positions of the group of permanent magnets; a controller for applying an electric current to the electromagnet on the basis of a detected signal from the positional sensor; and a power generating section for obtaining power from a coil of the electromagnet. A rotation mode and a power generation mode are repeated, so that power generation is performed while a function as a motor is exhibited.

Abstract: A combination of a torque-generating apparatus with an alternator/generator. The torque-generating apparatus comprises a first assembly (10, 25) including a generally cylindrical member of magnetically soft material and having a longitudinal axis, and a second assembly (2) arranged coaxially within the first assembly and including an electromagnetic winding (4). The first assembly (10, 25) and the second assembly (2) are rotatable relative to each other about the axis. Relative rotation between the first (10, 25) and second (2) assemblies induces a magnetic field which generates rotational torque between the first and second assemblies. Rectification means (31) is provided to convert alternating current electrical output from the alternator/generator (22) to provide D.C. current to the electromagnetic windings (4) of the torque generating apparatus to generate an electromagnetic braking effect.

Abstract: A permanent magnet electric machine (i.e.: motor/generator) having a magnetic flux circuit including a stator and a permanent magnet rotor mounted for rotation about an axis relative to the stator. The stator has an electric circuit with windings electro-magnetically coupled to the magnetic circuit. The stator is of material having a Curie temperature, wherein magnetic flux circulation through the stator material is impeded when the stator material acquires a temperature above the Curie temperature. The stator includes heat conducting layers and magnetic flux conducting layers, where the thermal conductivity of the heat conducting layers is greater than the thermal conductivity of the magnetic flux conducting layers. By this means the overall thermal conductivity of the stacked stator assembly is improved and means for quickly effecting shutdown of the electric machine are provided with a heat exchanger thermally coupled to the stator, thereby regulating magnetic flux circulation through the stator material.

Abstract: This invention is a back EMF permanent electromagnetic motor generator and method using a regauging process for capturing available electromagnetic energy in the system. The device is comprised of a rotor with magnets of the same polarity; a timing wheel in apposition to a magnetic Hall Effect pickup switch semiconductor; and a stator comprised of two bars connected by a permanent magnet with magnetized pole pieces at one end of each bar. There are input and output coils created by wrapping each bar with a conducting material such as copper wire. Energy from the output coils is transferred to a recovery rectifier or diode. The magnets of the rotor, which is located on a shaft along with the timing wheel, are in apposition to the magnetized pole pieces of the two bars. The invention works through a process of regauging, that is, the flux fields created by the coils is collapsed because of a reversal of the magnetic field in the magnetized pole pieces thus allowing the capture of available back EMF energy.

Abstract: The radial/rotary propulsion system of the present invention features a flywheel having concentric rings of permanent magnets attached to one or both sides or embedded into the flywheel. These permanent magnets interact with DC powered electromagnets which, when selectively energized, impart rotary motion to the flywheel. By arranging the permanent magnets in concentric rings, better control of both speed and torques may be obtained. In addition, in a regenerative mode, inertia of the flywheel is reconverted to electrical energy by either additional permanent magnet/coil combinations or through the switching of the electromagnet coils normally used for rotating the flywheel. A controller/sequencer constantly receives input signals for throttle, braking, flywheel rotational position, and battery level, and in response provides signals to control activation of electromagnets for drive, braking, and regeneration.

Abstract: A brushless rotary electric machine includes a stator having an annular armature core with first radial teeth at the outer periphery thereof and second radial teeth at the inner periphery thereof and an armature winding wound between the teeth, a rotor having a pair of first and second rotary cores disposed tandem in the axial direction thereof, and a field coil. Each of the first and second rotary cores has a pair of coaxial outer and inner cylindrical pole members respectively facing the first and second radial teeth, a center core and a disk member magnetically connecting the pair of coaxial cylindrical pole members and the center core. The stator is accommodated by a first space defined by the outer and inner cylindrical members of the pair of first and second rotary cores. The field coil is accommodated by a second space defined by the inner cylindrical pole member and the center core of the first and second rotary cores.

Abstract: An electrical generating system includes an electric motor coupled to a variable power source. A variable coupling is connected to an output shaft of the motor. The variable coupling includes opposed first and second plates each having permanent magnets affixed thereto and arranged such that rotation of the first plate by the motor causes the second plate to rotate by repulsive magnetic force. A switching mechanism adjusts the variable coupling. A gear assembly having a high transmission ratio is connected to the variable coupling. Preferably, at least one electrical generator is connected to the gear assembly for generating electricity.

Abstract: A differential speed change unit is installed in a housing at a position near an engine and arranged coaxial with a common axis, and a two-rotor type motor/generator unit is installed in the housing at a position away from the engine and arranged coaxial with the common axis. The motor/generator unit has inner and outer rotors and a wiring. An inner rotor shaft is connected with the inner rotor to rotate therewith. The inner rotor shaft extends coaxially with the common axis to be operatively connected to the differential speed change unit. An outer rotor shaft is connected with the outer rotor to rotate therewith. The outer rotor shaft extends coaxially with the common axis to be operatively connected to the differential speed change unit. The housing has a split section at which the housing is dividable into two housing parts, and the split section is positioned between the differential speed change unit and the motor/generator unit.

Abstract: The reversible multiphase rotary machine includes a device (3) for supplying current to the windings (12-14) of the stator, which is produced in the form of a mechanical inverter (2) able to be coupled to the aforementioned shaft of the machine and connected to the windings (12-14) of the stator.

Abstract: A concatenated motor assembly for providing rotational power that includes a continuous rotatable shaft cooperating with a first motor module assembly. The first motor module assembly communicates with a motor coupling unit, which in turn communicates with a second motor module. The second motor module and the motor coupling unit each cooperate with the rotatable shaft. The first and second motor modules are wound rotor electric motor. The first motor module assembly generates and provides an induced current to the motor coupling unit, which in turn provides power input to the second motor module assembly.

Abstract: A motor/generator has its stationary portion, i.e., the stator, positioned concentrically within its rotatable element, i.e., the rotor, along the axis of rotation of the rotor. The rotor includes a Halbach array of magnets. The voltage and power outputs are regulated by varying the radial gap in between the stator windings and the rotating Halbach array. The gap is varied by extensible and retractable supports attached to the stator windings that can move the windings in a radial direction.

Abstract: A multi-shaft, multi-layer motor has a stator coaxially disposed between inner and outer rotors which are driven independently by a compound current. For cooling stator coils, first through last branch coolant passages are arranged around the axis. The upstream ends of the first through last branch passages are arranged in sequence circumferentially along a distributing circumferential passage in a direction away from a common introduction port for introducing the coolant into the distributing circumferential passage, and the downstream ends of the first through last branch passages are distributed in sequence circumferentially along a collecting circumferential passage in a direction toward a common discharge port for discharging the coolant from the collecting circumferential passage.

Abstract: An integrated motor and clutch assembly is provided, which includes a housing that rotatably supports an input shaft and an output shaft. A selectively engageable friction clutch is disposed between the input shaft and the output shaft for transferring torque therebetween. The friction clutch includes an outer hub connected for rotation with the output shaft. The integrated motor and clutch assembly also includes a motor having a rotor non-rotatably connected to the outer hub of the friction clutch and disposed coaxial with the input and output shafts. The motor also includes a stator secured to the housing and disposed concentric with the rotor.

Abstract: In control apparatus and method for at least one electrical rotating machine, two rotors are disposed in the electrical rotating machine on the same axis of rotation and being driven independently of each other by means of a generated compound current and are associated with at least one stator and a position of at least one of the rotors is controlled in such a manner that a maximum value of the compound current is reduced as low as possible.

Abstract: A magnetic bearing control device that can operate a motor with low noise, has a simple system construction and is compact and inexpensive comprises: at least a pair of opposed electromagnets for supporting a suspended unit without contact; a motor M for rotating the suspended unit; and a controller for driving and controlling them. A DC/DC converter 13 supplies a driving power to an inverter 14 for driving the motor M. The inverter 14 for driving the motor M uses both PWM and PAM control schemes to drive and rotate the motor M.

Abstract: The radial/rotary propulsion system of the present invention features a flywheel having concentric rings of permanent magnets attached to one or both sides. These permanent magnets interact with DC powered electromagnets which, when selectively energized, impart rotary motion to the flywheel. By arranging the permanent magnets in concentric rings, better control of both speed and torques may be obtained. In addition, in a regenerative mode, inertia of the flywheel is reconverted to electrical energy by either additional permanent magnet/coil combinations or through the switching of the electromagnet coils normally used for rotating the flywheel. In alternated embodiments, regeneration is accomplished with alternators interacting with other magnets of the flywheel. The regenerative mode is also helpful in braking the flywheel as its inertial energy is converted to electrical energy.

Abstract: An electric rotating machine is equipped with a middle core, an outer core disposed outside the middle core which rotates relative to the middle core, and an inner core disposed inside the middle core which rotates relative to the middle core. The middle core comprises plural plates disposed in an axial direction. The plural plates are connected in the axial direction by a connecting member, and joined to a first fixing member. The inner and outer circumferential surfaces are finished in the state where the plates are joined only to the first fixing member, and the opposite side to the first fixing member is joined to a second fixing member after finishing.

Abstract: A torque motor, especially a fuel cell torque motor, converts chemically stored energy of liquid or gaseous fuels, directly inside the torque motor while avoiding a separate installation of devices, into mechanical energy for driving at least one consumer. The torque motor is provided with fuel cells that serve as an internal energy source, the fuel cells being arranged in the stator around the rotational axis of the motor in an annular manner. The torque motor includes a rotor and stator with permanent magnets arranged on the rotor and with armature windings located in the stator. The armature windings are supplied with current from a commutator having electronic power components. Fuel cell modules and fuel cell supply and control elements are integrated in the commutator in a structurally modular-like manner.

Abstract: The present invention provides a flywheel system with a variable speed synchronous reluctance motor-generator and a variable speed permanent magnet generator for providing backup power. The flywheel system incorporates rotating elements supported by electromagnetic bearings. Electric power provided by the backup generator maintains electromagnetic bearing operation during that portion of the coast down period when shaft speed falls below the minimum required for operation of the synchronous reluctance motor-generator.

Abstract: A spinning top rotor generator system comprises: a stator including a plurality of windings provided on an armature iron core; a rotor supported at the center of the stator by means of a rotary structure, a pole iron core having a plurality of windings provided thereon for generating a magnetic flux, by an external direct current power source applied therefor, to generate a revolving magnetic field and then induce an electromotive force on the stator armature correspondingly, by which an alternating current is outputted through a plurality of leads connected to the armature windings when the rotor rotates; wherein the stator and the rotor are held by flexible frames to be normal to each other, a downward end of the rotor shaft having a tapered tip supporting a majority of weight by the end thereof on a bearing base; a auxiliary motor, held flexibly on the top of the generator rotor, driving another end of the rotor shaft to turn the rotor turning around the tapered tip, functioned as the rotation center.

Abstract: A starter generator for an internal combustion engine including: a rotating electric machine having a magnet rotor mounted to a crankshaft of the internal combustion engine, and a stator with a three-phase first armature coil and a three-phase second armature coil; a first battery and a second battery connected in series or in parallel; a first driver circuit provided between the first armature coil and the first battery, and a second driver circuit provided between the second armature coil and the second battery; and an inverter that converts voltages of the first battery and the second battery into an AC voltage, wherein drive currents are supplied to the first armature coil and the second armature coil from the first battery and the second battery through switch circuits in the first driver and the second driver, when the engine is started, and induced voltages of the first armature coil and the second armature coil are supplied to the batteries through rectifier circuits in the first driver and the second

Abstract: A vehicle, having an engine (20) and a transmission (26), also includes an integrated assembly (24) between the engine (20) and transmission (26) which includes both a torque converter assembly (32) and an integrated starter-generator (ISG) assembly (36). The ISG assembly (36) is mounted between the torque converter assembly (32) and the transmission (26), with an ISG rotor (56) rotationally coupled to an impeller (42) through an assembly having compliance to allow for proper assembly and operation of the integrated assembly (24).

Abstract: A motor/generator comprises a stator (2) having plural coils (C1-C14), and plural rotors (3, 4) disposed coaxially with the above-mentioned stator and driven by a compound current. The phase difference between the currents (70, 71) driving the rotors (3, 4) is arranged to be other than 180 degrees. Thereby, the utilization factor of the voltage of the direct current power supply (10) is improved.

Abstract: A torque-generating apparatus comprises a first assembly (10, 25) including a generally cylindrical member of magnetically soft material and having a longitudinal axis and a second assembly (2) arranged coaxially within the first assembly and including an electromagnetic winding (4). The first assembly (10, 25) and the second assembly (2) are rotatable relative to each other about the axis. Relative rotation between the first (10, 25) and second (2) assemblies induces a magnetic field which generates rotational torque between the first and second assemblies.

Abstract: The invention relates to a current-transfer assembly for electric machines, comprising a shaft (22) with electrically conductive slip elements (12, 14, 16, 18) originating from and coaxially surrounding said shaft, said elements supporting carbon brushes. According to the invention, various electric phases are connected to slip elements that are insulated from one another, by means of current paths that lead to the windings of the electric machine. To guarantee that temperature fluctuations do not adversely affect the current transfer, the slip elements are configured as disc elements that consist of or contain carbon material.

Abstract: A brushless electrical machine for converting between electrical and mechanical energy includes a rotor supported on bearings for rotation about an axis of rotation, and a stator that is stationary and magnetically acts upon the rotor. The rotor includes two ferromagnetic rotor portions separated by a magnetic insulator, forming an axial armature air gap between the ferromagnetic rotor portions. At least one of the two ferromagnetic rotor portions has multiple axial extending protrusions facing the axial armature air gap around a circumference. An air core armature having multiple phase windings is located in the axial armature air gap. A ferromagnetic yoke and homopolar flux generator are mounted to the stator. The homopolar flux generator generates homopolar flux in the protrusions of the rotor and the ferromagnetic yoke forms two rotor-to-stator air gaps with the rotor.

Abstract: An apparatus comprises a stator coil for conducting an electrical input current to activate the stator coil. A magnetic structure is for magnetically interacting with the stator coil to produce mechanical output power and is electrically isolated from the stator coil. The mechanical output power is output by an output shaft fixed to the magnetic structure. The apparatus further comprises a pickup coil configured to be electromagnetically coupled to the stator coil and the magnetic structure to induce an electrical output current. The output current is output by an output line electrically connected to the pickup coil. An electrical load is electrically connected to the output line to be powered by the electrical output current.

Abstract: An AC motor-generator includes a rotor made up of a first inductor core and a second inductor core arrayed in an axial direction of a rotary shaft. A plurality of permanent magnets are arrayed at an interval of 2&pgr; in electrical angle of an armature away from each other in the periphery of each of the first and second inductor cores. Each permanent magnet is magnetized in a radius direction of the first and second inductor cores so as to be opposed to a magnetomotive force produced by a field winding, thereby resulting in quick disappearance of the magnetic flux of the field upon disappearance of the magnetomotive force from the field winding.

Abstract: A starter/generator assembly 10 which is adapted for use within a vehicle of the type having a crankshaft 12 and a torque converter 14. The assembly 10 includes a stator 18 and a rotor 20 which is isolated from the torque converter 14.

Abstract: The motor/generator according to this invention is provided with a first rotor (23), a second rotor (21) and a stator (22) provided with a plurality of stator coils (1-6). The first rotor (23) is provided with magnetic poles by a magnet. The second rotor (21) is provided with magnetic poles by a magnet and a plurality of rotor coils (A-D). The motor/generator functions as a magnetic coupling by creating an equal number of magnetic poles in the first rotor (23) and the second rotor (21). When the first rotor (23) and the second rotor (21) are rotated by supplying a polyphase alternating current to the stator coils (1-6), a part of the rotor coils (A-D) are excited and the number of magnetic poles of the second rotor (21) is varied to allow independent rotation of the first rotor (23) and the second rotor (21).

Abstract: A high-power electrodynamic machine operates at a relatively high rotational speed and has dual rotors. In a preferred generator embodiment, one relatively massive first rotor having a magnetic device integral therewith is dedicated to the main generator. The exciter generator, which is relatively less massive, is isolated on a second rotor, which has a magnetic device integral to it. Only three bearings are required. The distance between the two bearings for the first rotor is relatively short, and the first rotor is relatively stiff, both of which facilitate operation of the first rotor below the critical speed. The junction of the first and second rotors further includes support of a junction end of the second rotor. The second rotor is driven by a prime mover via the first rotor. Means for providing electrical connections between the magnetic devices of the first and second rotors is also provided.