Abstract: A fault protection system and method of fault protection for permanent magnet machine (PMM)-based systems that utilize machine neutral decoupling (MND) to shut down a shorted winding and/or to isolate a short-circuit fault to prevent damage to a permanent magnet machine and to any downstream components are provided. The invention may be used for high-reactance and/or high current PMM-based systems, such as are commonly found in industrial and aviation applications.

Abstract: A multiple output synchronous generator in accordance with the instant invention comprises a stator having a first stator winding having a number of poles p and a second stator winding having a number of poles 2*p*n where p and n are any whole numbers, the first and second stator windings being wound utilizing a 60.degree. phase belt winding configuration such that the first stator winding is magnetically decoupled from the second stator winding preventing interaction therebetween. The generator additionally comprises a rotor rotatably disposed within the stator defining an airgap therebetween. The rotor has a first field winding of a first polarity and a second field winding having a second number of windings wound thereon for generating a flux across the airgap such that the flux induces a voltage in the first and second stator windings.

Abstract: An electric power starter generator system comprises a synchronous generator and an induction motor/generator mutually coupled to a shaft being driven to an external prime mover. The synchronous generator and the induction motor/generator are driven by the shaft at the same speed. The system includes a rectifier/inverter having ac terminals coupled to the output of the induction motor/generator, and dc terminals coupled to a dc bus. This rectifier/inverter allows bi-directional power flow to effectuate both power generation as well as electric start of the prime mover. The synchronous generator is excited by a commonly driven permanent magnet generator and a modulated exciter field control. The induction motor/generator is self-exciting through the rectifier/inverter once a voltage is established on the dc bus. The establishment of this voltage may be accomplished by a battery, or by connection of the synchronous generator's output to the input of the rectifier/inverter through a poly-phase contactor.

Abstract: The problem of providing isolated DC power in a 270 volt DC power system (10) has been resolved with the use of a DC--DC converter (44) for providing isolated DC power on busses (46-48) for powering pulsating loads (66), avionics DC loads (68) and AC loads (64). The use of the converter (44) further allows for reduction in size of ripple filters (92-94) and damper circuits (50-52).

Abstract: The problem of filtering DC power on a DC bus (46) in an electrical power generating system (10) is resolved using an active damper circuit (44). The active damper circuit (44) comprises a capacitor (CD) and a switching circuit (70) for alternately switching the capacitor (CD) into and out of parallel relationship with the DC bus (46).

Abstract: The problem of stator cooling in a dynamoelectric machine is resolved using manufacturing spaces (32) within stator slots (20) for flow of oil coolant. In order to secure stator winding conductors (30) within the slots, a spring wedge (36) provides a biasing force for biasing the conductors against movements within the slots.

Abstract: In a dynamoelectric machine which includes a rotor and a stator, an integral magnetic isolation and cooling system. A housing is disposed about the machine, the housing being fabricated of magnetically permeable material to define a flux path therethrough. A cooling jacket is sandwiched between the housing and the stator. The cooling jacket has coolant passages therein and is fabricated of non-magnetic material to isolate the flux path between the housing and the stator.

Abstract: An improved alternating current machine having interdispersed armature windings is disclosed. The AC machine comprises an armature core having a plurality of generally longitudinal slots and a plurality of winding groups. Each of the winding groups comprises a plurality of one-turn coil windings which are series connected to electrically adjacent windings of the winding group. Each winding has two generally parallel side portions disposed in non-adjacent ones of the slots. The side portions are joined at one end by an end turn which extends axially outward from one end of the armature core and each of the side portions have an end connection extending a distance axially outward from the other end of the armature core for connecting to a respective electrically adjacent end connection of its electrically adjacent winding. The winding groups are interdispersed about the armature core such that there are a plurality of fixed distances between the electrically adjacent windings.

Abstract: A high-power, high-voltage DC power supply includes a plurality of AC generators, each of which includes a rotor and one or more sets of armature windings wherein the rotors are linked together. A plurality of rectifiers are connected together in series and the armature windings are connected to the rectifiers such that each rectifier produces a fractional voltage which is combined with the fractional voltage developed by other rectifiers to develop a combined output voltage across all of the rectifiers. The armature windings are placed relative to one another such that a plurality of equally-spaced ripple peaks appear in the combined output voltage for each 360.degree. of each armature winding voltage. This in turn minimizes ripple magnitude leading to a desirable decrease in the overall power supply size and weight.

Abstract: In order to improve the efficiency of electric machines, by reducing losses caused by eddy currents induced by high frequency fluxes, the outer surface of the rotor, including the rotor pole face, has a plurality of circumferential grooves. The grooves are provided in axially spaced relation along the rotor. Preferably, the method of reducing losses includes the step of forming the grooves by laser cutting, which permits the width and spacing of the grooves to be minimized so as to maximize loss reduction by increasing resistance to eddy currents.