Abstract: A three-phase machine with a 2-pole stator (10) formed with a winding arrangement of a double-layer tooth-wound coil winding has m winding phases (U, V, W). The winding arrangement has at least one first double-layer tooth-wound coil (20) and one second double-layer tooth-wound coil (30). Each tooth-wound coil occupies a half of each of four respective adjacent slots (N) of the stator (10) with a winding phase (W). Each double-layer tooth-wound coil (20, 30) forms two concentrically arranged coils. The second double-layer tooth-wound coil (30) is arranged such that it is shifted by a pole pitch with respect to the first double-layer tooth-wound coil (20).

Abstract: An ac motor for high-torque drive has a transformer with a magnetic circuit with a central limb. Either the two ends or the two connected electrodes of the secondary winding of the transformer project at an angle to the longitudinal axis of the secondary winding; an armature rotor dielectrically bridges the two ends or the two connected electrodes, moving parallel to the longitudinal axis. The rotor forms two series-connected capacitors with the two ends or the two connected electrodes. An LC circuit is formed by the two capacitors in series to the total effective inductance of the power source, the electric transformer, the two ends or the connected electrodes and the armature. The impedance of the LC circuit is varied by the frequency of the power source supplying the primary winding of the transformer, in order to push required electric power from the power source to the series LC circuit.

Abstract: A linear motor for high velocity drive has a transformer which has a magnetic circuit with a central limb; the two ends of stacked unit- or fractional-turn secondary winding of the transformer project at an angle to the longitudinal axis of the central limb; an armature links the two ends, sliding parallel to the longitudinal axis. The armature has dielectrics to form two series-connected capacitors in conjunction with the two ends. The transformer's primary winding is connected to an ac or pulse power source. The resonant frequency for the LC circuit formed by the two capacitors in series to the total effective inductance of the power source, the electric transformer and the armature is determined. The frequency or the pulse rise time of the power source is matched to the resonant frequency, in order to supply adequate electric power from the power source to the series LC circuit.

Abstract: The DC voltage of electrical energy applied to a homopolar machine, is corted by transformer windings in response to rotor rotation within the magnetic field of the homopolar machine, to a different voltage level for supply to a load.

Abstract: An electrostatic actuator includes a stationary element having a plurality of driving electrodes arranged in a predetermined direction and with predetermined spaces in an isolated state on an insulating supporter, a movable element, disposed in contact with the stationary element, electric wires connected to the driving electrodes of the stationary element, and a driving voltage control section to apply to the driving electrodes voltages which cause a change in the relative position of the first and second members by a Coulomb's force of static electricity between the stationary element and the movable element, which is produced by switching the voltages to the driving electrodes, wherein the driving voltage control section includes a power source of high voltage and direct current, a high voltage switching portion and a driving control portion; the power source including a transformer for raising the voltage of high frequency current signals, and a rectifier for rectifying an output of the transformer to obt

Abstract: An electric machine according to various aspects of the invention includes a transformer having a rotating component for transmitting power from a stationary portion of the machine to a rotating portion of the machine, or vice versa. Both the rotating component and a stationary component of the transformer includes a winding, wherein the windings are disposed to be magnetically coupled. Current provided to the winding of the stationary component generates a magnetic field, which induces current in the winding of the rotating component.

Abstract: A three-phase generator includes an internal neutral junction to which one end of each of the windings of the generator is connected thereby forming a wye-connected generator. An air-core current transformer is disposed over each of the three conductors leading to the internal neutral junction for monitoring neutral current therein. A corresponding air-core current transformer is disposed over high-voltage terminals connected to the other ends of the generator windings. A shielded differential amplifier on the output of each air-core current transformer produces a signal corresponding to the difference between two bifilar half windings in its associated air-core current transformer. The difference currents from the neutral and high-voltage ends of each generator winding are compared, and, if their difference exceeds a predetermined threshold, a threshold circuit produces a trigger signal which is latched by a latching relay to produce a trip signal for use by the generator control system.

Abstract: An excitation system of a large dynamoelectric machine includes an excitation transformer having a liquid coolant system. The coolant system of the transformer is supplied with a liquid coolant, preferably from an existing source of de-ionized water, thereby permitting a smaller transformer to be used and/or the output rating of the transformer (and ultimately the output rating of the machine) to be increased, while using the same size transformer. The transformer may be disposed separate from, yet closely proximate, the machine.

Abstract: A common neutral bus is formed in a lower frame extension of a large three-phase generator by disposing three sets of neutral current transformers within the lower frame extension and interconnecting the three phases downstream of the neutral current transformers to form an internal neutral bus. The neutral bus is connected to an external neutral transformer through a neutral terminal of small size and low cost. Clamshell clamps are provided in the internal neutral bus for isolating the neutral ends of the generator winding for test purposes. Rigid support of the current transformers and a hollow copper tube passing therethrough permits use of light and low-cost hollow copper tubing in place of the relatively substantial and expensive neutral terminals conventionally required.

Abstract: Electrical power of high intensity is transmitted to a rotating electrode with the use of an apparatus, wherein a shaft is provided with a connecting joint which is rigidly connected to a cylindrical container serving as the rotating electrode. A trough filled with a low-melting alloy has a contact maker secured to it, and the latter has a flexible cable screwed thereto. A cover, which has the shaft passed through it, is insulatingly placed on the cover, and the shaft is provided with a disk, in the region of the cover.